Validation of the

DOCTORAT – UNIVERSITÉ AIX-MARSEILLE

ÉCOLE DOCTORALE COGNITION, LANGAGE, ÉDUCATION (ED 356) Validation of the French Depression Anxiety Stress Scales (DASS-21) and predictors of depression in an adolescent Mauritian population

Thèse de Doctorat en Psychologie de l’Université Aix-Marseille

Par Sajeda Ramasawmy

Directeur de thèse Professeur Pierre-Yves Gilles

Soutenance le 9 janvier 2015 Avec mention Très Honorable (avec les félicitations du jury)

Jury

Mme. Carole Fantini Jury international

Professeur en Psychologie, Faculté des Sciences psychologiques et de l'Education, Université Libre de Bruxelles.

M. Jacques Juhel

Professeur des universités, Directeur du Centre de Recherches en Psychologie, Cognition, Communication, Université de Rennes.

M. Pierluigi Graziani

Professeur en Psychologie, Directeur Département Psychologie, Lettres, Langues et Histoire, Université de Nîmes.

Lis, au nom de ton Seigneur, Celui qui a créé qui a créé l’homme d’une adhérence Lis! Ton Seigneur est le Très Noble Celui qui a enseigné par la plume, a enseigné à l’homme ce qu’il ne savait pas… 96 : 1-5

Le savoir est certes Ta création. Cette thèse n’aurait jamais été faite sans la permission de Celui qui m’a démontré qu’il faut que j’aille à la quête du savoir, de Son Savoir - car ne sont égaux celui qui ignore et celui qui comprend Ses Signes. Au fil des ans, la psychologie n’a cessé de nous rapprocher … Ne serait-ce que pour cela, cette thèse m’est inestimable ! Ce fut donc un cheminement spirituel avant d’être un accomplissement professionnel et l’aboutissement d’une recherche scientifique. Avec du recul, je suis convaincue qu’une thèse est loin d’être un travail en solitaire car elle m’a permis de faire des rencontres qui me marqueront à jamais. Je remercie d’abord Professeur Pierre-Yves Gilles pour la confiance qu’il m’a accordée en acceptant d’encadrer ce travail malgré la distance et le décalage horaire. Il a su m’indiquer les bonnes directions de recherche, m’a donné le temps de cogiter, entamer et surtout de prendre plaisir à accomplir chaque étape de cette thèse. Il a ce talent de savoir tout expliquer en des termes tellement apaisants. J’ai été très sensible à sa générosité, son humilité et surtout sa disponibilité durant ce travail doctoral. Étant donné que j’étais dans des conditions exceptionnelles sous les tropiques, par 30˚C à l’Ile Maurice, il a aussi pris en main toutes mes démarches administratives au sein de l’école doctorale durant ces quatre dernières années, bref il m’a choyée. Je souhaite remercier Professeure Carole Fantini et Professeur Jacques Juhel qui ont accepté d’être les rapporteurs de ce travail car leur point de vue m’a permis de voir d’autres perspectives à cette recherche. Je remercie également Professeur Pierluigi Graziani d’avoir accepté de présider le jury. Mes remerciements vont aux nombreux et nombreuses élèves anonymes qui ont participé à cette recherche. J’ai une pensée particulière pour les rectrices et recteurs qui ont mis à ma disposition toute l’infrastructure nécessaire pour la passation des questionnaires au sein de leurs établissements scolaires - Madame Fawzia Collendavelloo, Madame Josiane How Kong Fah, Monsieur Hassam Amide, Monsieur Raouf Nojib, et Monsieur Jacques Mallié. Cette thèse m’a aussi permis de rencontrer Mme Nazlee Dahal et sa fille, Zaynab. Nos partages m’ont été d’un enrichissement spirituel sans équivoque. 2

A maman… Je ne te remercierai jamais assez pour tout

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ABSTRACT

Depression is among the most common psychopathology for which treatment is sought in psychological and psychiatric practices and its impact at all levels including its economical outlay in the coming years has been estimated on a worldwide scale to surpass that of current illnesses such as infectious diseases and cardiovascular illnesses. Research has demonstrated that stress and anxiety levels, as early as in adolescence, are among factors that contribute to the development of depression. The aim of this research study is therefore to investigate the psychometric properties of the French Depression Anxiety Stress Scales (DASS-21; Lovibond & Lovibond, 1995) for its eventual use in the Mauritian adolescent population as a means to screen for depression, anxiety, and stress. Factor analyses were conducted on 1002 response sets and the three-factor structure of the DASS-21 was supported. Internal consistency was satisfactory and the scales demonstrated concurrent validity with other measures of depression, anxiety and stress. The construct validity of the scales was further strengthened with gender invariance. Finally, appraisal of stress was the psychological dimension which predicted best depression in the Mauritian adolescent population.

Keywords: Depression, anxiety, stress, adolescents, psychometric, Mauritius

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RÉSUMÉ

La détresse émotionnelle est souvent précurseur au développement des troubles psychologiques. La psychopathologie la plus fréquente dans le monde est la dépression et il a été estimé que d’ici quelques années, son impact économique sera supérieur à celle des maladies courantes telles que les maladies infectieuses et cardio-vasculaires. Des études ont démontré que le niveau de stress et d'anxiété sont des facteurs qui contribuent de façon significative au développement de la dépression et ce dès l'adolescence. L'objectif de cette thèse a été donc d'étudier les propriétés psychométriques de la version française de l’échelle Depression Anxiety Stress (DASS-21; Lovibond & Lovibond, 1995) pour son utilisation éventuelle à l’Île Maurice auprès des adolescents. L’étude de la validité de l’instrument comporte l’exploration de la validité de construit par le biais de la validité factorielle, l’étude de la cohérence interne et enfin par une analyse des validités convergente et divergente. La validité de construit de la DASS-21 a été renforcée puisque le fonctionnement différentiel des items en fonction du genre n’a pas été démontré. Enfin, il s’est avéré que le principal facteur de risque pour la survenue de la dépression chez les sujets mauriciens est le stress perçu (perception subjective de l’événement qualifié de stressant).

Mots-clés: Dépression, anxiété, stress, adolescents, psychométrique, Ile Maurice.

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TABLE OF CONTENTS PAGE GENERAL INTRODUCTION ..................................................................................................... 14 Measurement of psychological constructs .................................................................. 16 The DASS ..................................................................................................................... 17 Psychiatry and psychology in Mauritius ...................................................................... 19 Rationale for the current research .............................................................................. 20

CHAPTER ONE: ADOLESCENT STRESS, DEPRESSION & ANXIETY........................ 22 Section one: stress ...................................................................................................... 23 1.1.1 Definition of stress ......................................................................................... 23 1.1.2 The transactional model of stress and coping ............................................... 24 Primary appraisal ......................................................................................................... 25 Secondary appraisal ..................................................................................................... 26 1.1.3 Coping ............................................................................................................ 27 1.1.4 Measurement of stress .................................................................................. 28 Measurement of appraisal ........................................................................................... 29 measurement of coping ............................................................................................... 30 1.1.5 Common stressors in childhood & adolescence ............................................ 31 1.1.6 Gender differences in adolescent stress and coping ..................................... 32 1.1.7 Adolescent stress: causal role for depression & anxiety ................................ 33 Section two: depression .............................................................................................. 35 1.2.1 Definition of depression ................................................................................. 35 1.2.2 Depressive disorders in adolescents .............................................................. 37 1.2.3 Prevalence of depression in adolescents ....................................................... 37 1.2.4 Gender differences in adolescent depression................................................ 38 1.2.5 Theories of depression ................................................................................... 39 The biological perspective ........................................................................................... 40 The hypothalamus-pituitary axis ................................................................................. 40 The prefrontal cortex ................................................................................................... 41 The behavioural paradigm ........................................................................................... 43 The hopelessness theory of depression ...................................................................... 45 Aaron Beck’s cognitive triad ........................................................................................ 45 1.2.6 Empirical studies on cognitive models ........................................................... 47 1.2.7 Diathesis-stress models.................................................................................. 48 1.2.8 Measures of depression ................................................................................. 49 Section three: anxiety ................................................................................................. 52 1.3.1 Definition of anxiety ...................................................................................... 52 1.3.2 Anxiety disorders in children and adolescents .............................................. 53 1.3.3 Diagnostic categories of anxiety disorders .................................................... 53 1.3.4. Differentiating pathological anxiety in youth ................................................ 58 1.3.5. Gender differences in anxiety ....................................................................... 59 6

1.3.6. Theories of anxiety ........................................................................................ 59 The state-trait theory of anxiety .................................................................................. 60 Measurement of state and trait anxiety ...................................................................... 61 The Behavioural Inhibition and Activation Systems (BIS-BAS)..................................... 62 Measurement of BIS and BAS ...................................................................................... 63 Section four: coexistence of depression & anxiety ...................................................... 65 1.4.1 Comorbidity of anxiety and depression ......................................................... 65 1.4.2 Temporal relationship between anxiety and depression ............................... 66 1.4.3 Influence of anxiety on symptom severity of depression .............................. 67 1.4.4 Theoretical explanations for comorbidity ...................................................... 67 1.4.5 The tripartite model ....................................................................................... 69 1.4.6 Differentiating anxiety from depression ........................................................ 71 1.4.7 Clinimetrics of the DASS scales ...................................................................... 73 1.4.8 Chapter summary and rationale for research ................................................ 75

CHAPTER TWO: CONSTRUCT VALIDITY OF THE FRENCH DASS-21.................... 77 Introduction ................................................................................................................ 78 Reliability: Cronbach’s alpha ......................................................................................... 79 Construct validity .......................................................................................................... 80 Key aspects in cross-cultural validation ........................................................................ 81 The DASS-21 .................................................................................................................. 85 The construct validity of the DASS-21 in adolescent samples ...................................... 86 Rationale for the current study .................................................................................... 87 Method ....................................................................................................................... 88 Participants ................................................................................................................... 88 Procedure ..................................................................................................................... 89 Measures ...................................................................................................................... 90 Statistical analysis ......................................................................................................... 90 Reliability: internal consistency .................................................................................... 91 Factor analytic procedure ............................................................................................. 91 Results ........................................................................................................................ 96 Normality testing .......................................................................................................... 96 Internal consistency ...................................................................................................... 96 Construct validity: factor analytic results ..................................................................... 97 Internal validity ........................................................................................................... 108 Discussion ................................................................................................................. 110

CHAPTER THREE: DIFFERENTIAL VALIDITY OF THE DASS-21 ......................... 115 Introduction .............................................................................................................. 116 Importance of gender invariance ............................................................................... 116 Gender invariance across the DASS ............................................................................ 119 Research rationale ...................................................................................................... 120 Method ..................................................................................................................... 121 Dataset and statistical procedure ............................................................................... 121 Results ...................................................................................................................... 124 Confirmatory factor analyses on gender .................................................................... 124 Gender differences on mean scores across age groups ............................................. 127 The stress scale: Two-way ANOVA ............................................................................ 127

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The stress scale: One-way ANOVA – girls........................................................... 128 The stress scale: One-way ANOVA – boys .......................................................... 128 The anxiety scale: Two-way ANOVA .......................................................................... 129 The anxiety scale: One-way ANOVA – girls ........................................................ 129 The anxiety scale: One-way ANOVA – boys ....................................................... 129 The depression scale: Two-way ANOVA .................................................................... 130 The depression scale: One-way ANOVA – girls .................................................. 130 The depression scale: One-way ANOVA – boys ................................................. 131 Independent samples t-tests ..................................................................................... 131 Discussion ................................................................................................................. 133

CHAPTER FOUR: EXTERNAL VALIDITY OF THE DASS-21 ..................................... 136 Introduction .............................................................................................................. 137 The evolution of the concept of validity ..................................................................... 137 Studies on the external validation of the DASS .......................................................... 139 Method ..................................................................................................................... 141 Participants ................................................................................................................. 141 Measures .................................................................................................................... 141 The French RCMAS (Reynolds & Richmond, 1999) .................................................... 141 The French MDIC (Berndt & Kaiser, 1999) ................................................................. 142 The French CISS (Endler & Parker, 1998) ................................................................... 143 Statistical analyses ...................................................................................................... 144 Results ...................................................................................................................... 145 Descriptive statistics ................................................................................................... 145 Concurrent and divergent validities ........................................................................... 146 Discussion ................................................................................................................. 154

CHAPTER FIVE: PREDICTORS OF DEPRESSION ......................................................... 156 Introduction .............................................................................................................. 157 Terminologies for co-existing syndromes ................................................................... 157 The separatist approach ............................................................................................. 158 The unitary approach .................................................................................................. 159 The question of temporal association ........................................................................ 160 The tripartite tenet ..................................................................................................... 161 Limitation of the tripartite model ............................................................................... 163 Barlow’s hierachical model ......................................................................................... 164 The BIS-BAS systems ................................................................................................... 165 The impact of co-existing depressive and anxious states ........................................... 166 Stress in the dynamic of depression and anxiety ....................................................... 167 Method – study I ....................................................................................................... 169 Dataset & statistical procedure .................................................................................. 169 Testing for temporal association between anxiety and depression ........................... 171 Results – study I ........................................................................................................ 173 Descriptive statistics and linear correlation................................................................ 173 Multiple regression analysis ....................................................................................... 173 Temporal association between anxiety and depression ............................................ 176 Discussion – study I ................................................................................................... 178

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Foreword to study II .................................................................................................. 179 Eysenck’s theory of personality .................................................................................. 180 Gray’s reinforcement sensitivity theory ..................................................................... 183 The revised Reinforcement Sensitivity Theory ........................................................... 185 The BIS-BAS theory: relationship with anxiety and depression .................................. 186 Method – study II ...................................................................................................... 189 Participants ................................................................................................................. 189 Procedure ................................................................................................................... 190 Measures .................................................................................................................... 190 Statistical analyses and design .................................................................................... 192 Results – study II ....................................................................................................... 194 Descriptive statistics ................................................................................................... 194 Linear correlation ........................................................................................................ 195 Regression analyses .................................................................................................... 198 Hierarchical multiple regression ................................................................................. 201 Temporal association between anxiety and depression ............................................ 204 Discussion – study II .................................................................................................. 206 General discussion of chapter five ............................................................................. 210

CHAPTER SIX: GENERAL DISCUSSION OF THE DISSERTATION ......................... 213 Limitation of research ................................................................................................ 214 Clinical utility and theoretical contribution ............................................................... 215 Future direction ......................................................................................................... 217

REFERENCES ............................................................................................................................. 218 APPENDIX SECTION ............................................................................................................... 266

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LIST OF FIGURES Figure 1: Transactional model of stress and coping ............................................. 24 Figure 2: The HPA system ..................................................................................... 41 Figure 3: The tripartite model of depression and anxiety .................................... 70 Figure 4: Map of Mauritius showing location of schools ..................................... 88 Figure 5: Distribution of boys and girls across the four schools .......................... 89 Figure 6: Scree Plot ............................................................................................... 98 Figure 7: One-factor model showing standardised estimates ........................... 102 Figure 8: Quadripartite model showing standardised estimates ....................... 103 Figure 9: Two-factor model showing standardised estimates ........................... 104 Figure 10: Hierarchical bi-factor model showing standardised estimates ......... 105 Figure 11: Three-factor model showing standardised estimates....................... 107 Figure 12: Distribution of age category and gender .......................................... 122 Figure 13: Three-factor model for girls .............................................................. 125 Figure 14: Three-factor model for boys ............................................................. 126 Figure 15: Normality tests for multiple regression analysis ............................... 172 Figure 16: Eysenck's bi-dimensional model of personality ................................ 182 Figure 17: Eysenck's new model of personality traits ........................................ 183 Figure 18: Position in factor space of sensitivity to reward and punishment .... 184 Figure 19: Distribution of gender in each age category ..................................... 189 Figure 20: Tests of normality for regression analysis ......................................... 200

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LIST OF TABLES Table 1: Descriptive statistics for the three DASS-21 scales ................................ 96 Table 2: α values for the DASS-21 across studies in adolescent populations ...... 97 Table 3: Factor loadings above .30 using promax rotation. ............................... 100 Table 4: Phi-values (φ) between the three factors on the DASS-21 .................. 108 Table 5: Summary of CFA results for different models tested ........................... 108 Table 6: Pearson correlation values between the three DASS-21 scales ........... 109 Table 7: Means & standard deviations for each scale across the two genders . 121 Table 8: Distribution of gender across age groups............................................. 123 Table 9: Phi (φ) values between latent factors .................................................. 124 Table 10: Summary of fit indices for the three-factor model for each gender .. 126 Table 11: Means and standard deviations for each scale across gender and agegroups and results of t-tests ..................................................................................... 127 Table 12: Descriptive statistics for scales of DASS-21, RCMAS, CISS & MDIC .... 145 Table 13: Intercorrelation values between scales and subscales of the RCMAS147 Table 14: Correlation values between scales and subscales of the CISS ........... 148 Table 15: Correlation values between scales and subscales of the MDIC ......... 149 Table 16: Pearson's correlations between scales and subscales ....................... 150 Table 17: Factor loadings above .30 using varimax............................................ 153 Table 18: Factor loadings above .30 using promax ............................................ 153 Table 19: Multiple Regression Analysis for variables predicting scores on the DASS-21 depression scale ......................................................................................... 175 Table 20: Frequency table showing the number of depressed (on DASS-21 depression) and anxious (on DASS-21 anxiety) cases across the sample ................. 177 Table 21: Means and standard deviations across the three DASS-21 scales in comparison to adolescents in Belgium and Australia ............................................... 177 Table 22: Skewness and Kurtosis values for each scale ..................................... 194 Table 23: Means & standard deviations across the scales and subscales ......... 195 Table 24: Inter-correlations between scales ...................................................... 196 Table 25: Multiple Regression Analysis for variables predicting scores on the BDIII scale ....................................................................................................................... 201 Table 26: Summary of hierarchical regression analysis for variables predicting depression................................................................................................................. 203 Table 27: Frequency table showing the number of depressed (on BDI-II) and anxious (on DASS-21) cases across the sample ........................................................ 204

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LIST OF APPENDICES Appendix A: The DASS-42 ................................................................................... 267 Appendix B: The DASS-21 ................................................................................... 269 Appendix C: The Perceived Stress Scale ............................................................. 270 Appendix D: Coping Inventory for Stressful Situations ...................................... 271 Appendix E: DSM criteria for Disruptive Mood Dysregulation Disorder ............ 272 Appendix F: DSM criteria for a Major Depressive Disorder (MDD) .................... 273 Appendix G: DSM criteria for Persistent Depressive Disorder (Dysthymia)....... 274 Appendix H: Premenstrual Dysphoric Disorder.................................................. 276 Appendix I: The Beck Depression Inventory – II ................................................. 277 Appendix J: French version of the MDIC ............................................................ 279 Appendix K: The RCMAS ..................................................................................... 281 Appendix L: The BIS/BAS scales .......................................................................... 282 Appendix M: The French DASS-21 ...................................................................... 283 Appendix N: DASS-21 one-factor solution (unrotated) ...................................... 284 Appendix O: DASS-21 two-factor solution ......................................................... 285 Appendix P: The French RCMAS ......................................................................... 287 Appendix Q: The French CISS ............................................................................. 288 Appendix R: PCA on 23 scales & subscales......................................................... 289 Appendix S: Covering letter to participants ....................................................... 290 Appendix T: The French BDI-II ............................................................................ 291 Appendix U: The French BIS-BAS ........................................................................ 293 Appendix V: The French PSS ............................................................................... 294

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LIST OF ABBREVIATIONS

BAS BDI-II BIS CFA CISS DASS-21 DASS-42 DSM EFA FFFS FFS JSH MDD MDIC NA PA PCA PFC PH PSS RCMAS RST

Behavioural Activation System Beck Depression Inventory (2nd version) Behavioural Inhibition System Confirmatory Factor Analysis Coping Inventory for Stressful Situations Depression Anxiety Stress Scales (21 item-version) Depression Anxiety Stress Scales (42 item-version) Diagnostic and Statistical Manual for mental disorders Exploratory Factor Analysis Fight-Flight-Freeze System Fight-Flight System Joint Subsystem Hypothesis Major Depressive Disorder Multiscore Depression Inventory for Children Negative Affect Positive Affect Principal Component Analysis Prefrontal Cortex Physiological Hyperarousal Perceived Stress Scale Revised Children Manifest Anxiety Scale Reinforcement Sensitivity Theory

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GENERAL INTRODUCTION

General Introduction

Clinical psychologists working with adolescents are primarily concerned with the latter’s emotional and psychological health. The understanding of adolescent psychopathology focuses not only on biological models of illnesses but also on cognitive and behavioural paradigms (Akiskal, 2008). The ultimate goal of such approaches to clinical research and practice is to alleviate the distressing symptoms that interfere with the individual’s emotional well-being. The practice of clinical psychology entails therapeutic intervention at an idiographic1 level based on research findings generalised from a nomothetic2 approach. In fact, there is no contradiction to proceed in this way in clinical practice as the nomothetic approach is useful in that it helps in the understanding of general psychological dynamics involved in behaviours and cognitions, and it aids at discerning normative dimensions from rare or abnormal probability of psychological symptomatology. It also informs treatment intervention in such a way that it sets therapeutic guidelines which address efficacy of treatment intervention for specific psychopathologies and/or for samples’ idiosyncrasies such as gender and age groups (Barlow & Nock, 2009).

1

Idiographic implies an understanding at the individual level.

2

Nomothetic implies a global understanding based on observation of a group of individuals.

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MEASUREMENT OF PSYCHOLOGICAL CONSTRUCTS

The practice of clinical psychology is thus a matter of individual differences and as such, self-report approach to measurement of psychological dimensions has traditionally been the method of choice in both clinical research and practice. Since the 1950s, researchers in the field of psychological test construction have made it a golden rule for psychological dimensions to have a precise definition and selection of items that reflect the characteristics of the said dimension (Clark & Watson, 1995). This process is two-faceted: the nomothetic span determines a pattern of significant associations between measures of similar and dissimilar psychological dimensions, in other words nomothetic span establishes divergent, convergent and concurrent validities of the measurement (Strauss & Smith, 2009; Whitely, 1983). The second, construct representation, indicates how well items or sets of items (dependent variables) are actually measuring the psychological dimension under investigation (Embretson, 1983). The goal of construct representation is thus to test a theory where a particular process (e.g. cognition) gives rise to a specific response (e.g. behaviour) (Borsboom, Mellenbergh, & Van Heerden, 2004). In summary, self-report measurement in clinical psychology needs to possess both construct representation or internal validity and nomothetic span, i.e. external validity.

There is increasing pressure in the practice of clinical psychology to provide empirical evidence to substantiate severity of psychological

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symptoms, and efficacy of therapeutic intervention (Sexton, Gilman, & Johnson—Erickson, 2005). Consequently, numerous self-report instruments for evaluating psychological constructs have been developed over the past decades in different languages for several ethnic groups, with the tendency to develop these psychometric instruments with fewer items to facilitate the testing process (Sinclair et al., 2011). In comparison to interview methods which often bear the risk of responses being biased due to interviewer and social stereotypes, self-report measures validated in the language of the respondent are useful in the assessment of the current psychological state of the individual so long as the respondent is insightful to feelings, thoughts, and behaviours.

Additionally, self-report measures are quick, easy and

inexpensive to administer, and are most efficient when needed to assess large groups of individuals (Schuman & Presser, 1996).

THE DASS Although emotional distress such as anxiety and stress are undoubtedly among the most common psychopathologies for which treatment is sought in psychological practice (Borkovec, Echemendia, Ragusea, & Ruiz, 2001), unipolar depression is expected to become by 2030 the leading cause of burden due to illness3 (WHO, 2004). Since these three psychopathologies are likely to emerge in adolescence, then it is crucial for clinical psychologists to measure the severity of symptoms related to these dimensions in this

3

Burden of illness is the relative impact of illnesses and injuries on populations. It quantifies financial loss due to disease and injury after treatment, rehabilitation or prevention efforts in the health system and society generally.

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vulnerable age group with adapted self-report measures.

Self-report

measures can in no way be equivalent to a formal clinical interview instead, they can be used as an adjunct tool to substantiate clinical formulation in order to implement and monitor effective prevention and treatment strategies.

One promising psychometric tool that elicits interest both in clinical practice and research worldwide is the Depression Anxiety Stress scales (DASS; Lovibond & Lovibond, 1995). There are two versions to the DASS: the 42-item version (DASS-424) and a shorter version which consists of half of the number of items of the original scale, the DASS-215. Both are self-report measures for symptom-severity of autonomic arousal, characteristic of anxiety; and level of anhedonia6, hopelessness and devaluation of life which define depression. Stress is measured as a syndrome distinct from both anxiety and depression which include symptoms of irritability and tension among others. Altogether the interplay of these three dimensions makes the DASS scales appealing in clinical research and practice for the identification of different forms of emotional distress.

Over the last two decades, the

translated versions of the DASS scales have become popular in both community and clinical samples worldwide (Tran, Tran, & Fisher, 2013). As the external and internal validities of the DASS-21 have been examined in the current research using a sample of Mauritian adolescents, the next section 4

See Appendix A See Appendix B 6 Anhedonia is defined as the inability to experience pleasure from activities usually found enjoyable, e.g. exercise, hobbies, music, sexual activities or social interactions. 5

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will briefly present some facts of the status of psychology and psychiatry in Mauritius.

PSYCHIATRY AND PSYCHOLOGY IN MAURITIUS

Mauritius, a subtropical island of 2000 km2, situated in the Indian Ocean off the eastern coast of Madagascar, has a multiethnic population of 1.2 million consisting of 68% Indian descent, 27% of African origin, 3% Chinese, and 2% European (French and British) descent (“Census,” 2000). Mauritius was colonised successively by the French and British empires since the 18 th century and the official language is English but Creole (pidgin French) and French remain the two most spoken languages. Cultural influence from France and England still prevails although the country gained its independence from England since 1968 (“Mauritius,” 2013).

Since 1997, the country has been developing its mental health services, with the opening of psychiatric units in its five major hospitals. Nationally, there are about twenty psychiatrists and roughly the same number of practicing clinical psychologists altogether in the public and private sectors. There is a paucity of studies and statistical data on psychiatric illnesses in the population and the few available from public hospitals concern suicide and self-inflicted injuries. About 55.7% of cases of intentional self-harm and intentional self-inflicting injuries in 2009 concerned women and in 2010, this

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figure rose to 63.9% (“Injury and poisoning,” 2009, 2010). There has since been no data published in this category by the Ministry of Health.

Adolescents represent 16% of the Mauritian population with 50.7% males (“Statistics in Mauritius”, 2013). Among African countries, Mauritius has the highest rate of suicide per 100,000 adolescents with approximately 11.3 deaths by suicide of adolescents per year (Wasserman, Cheng, & Jiang, 2005). According to this survey, Mauritius was ranked 11th whilst France was ranked 49th for countries with the highest rate of suicide among the 15-19 year olds. Approximately, 10.4% of cases of suicide in Mauritius concern adolescents and it represents 29.2% of deaths in this age group (“Deaths due to external causes,” 2011).

RATIONALE FOR THE CURRENT RESEARCH

Such figures on the suicide rate in Mauritius emphasise the need to have a psychometric measure adapted to the Mauritian adolescent population to enable clinical psychologists to screen for depression, a risk factor for suicidality (Hawton, Casañas, Comabella, Haw, & Saunders, 2013). Research also demonstrated that anxiety often precedes the onset of depression, and stress is a risk factor for the development of both, depression and anxiety (Grant & Compas, 1995; Kessler, 1997). The current research therefore attempts to examine the psychometric properties of the French DASS-21 for

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its eventual use in the Mauritian adolescent population because currently there is no psychometric tool validated for this population.

This dissertation is divided into six chapters addressing the research questions pertaining to the validation of the French DASS-21. Theoretical concepts of stress, depression, and anxiety based on biological, behavioural and cognitive models are explicated in Chapter One.

The intrinsic

relationship between anxiety and depression is stressed therein and relevance of the DASS-21 in the assessment of depression and anxiety is also addressed. The chapter concludes with rationales for research on the DASS21 in a Mauritian adolescent sample. At the outset of Chapter Two, a brief explanation on psychometrics with reference to the importance of establishing the construct validity of an instrument is provided. Additional information is given on the psychometric properties of the DASS-21 based on research conducted internationally. The methodology and the results of the empirical investigation on the construct validity of the DASS-21 are also presented and the chapter ends with a discussion on the findings. Chapter Three focuses on the differential validity of the DASS-21 with regard to gender differences whilst Chapter Four examines its concurrent and divergent validities.

Chapter Five aims at identifying psychological dimensions,

represented by scales and subscales of measures, likely to predict depression scores in a Mauritian adolescent sample. The general discussion of the entire dissertation, strengths, theoretical contributions, limitations and direction for future research are developed in Chapter Six.

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CHAPTER ONE: ADOLESCENT STRESS, DEPRESSION & ANXIETY

Chapter 1: adolescent stress, depression & anxiety

SECTION ONE: STRESS

1.1.1

DEFINITION OF STRESS

More than a century after adolescence was equated to a period of storm and stress, this view was actually a turning point for an upsurge of research studies on the question of adolescent stress (Arnett, 1999). Although some psychologists (e.g. Offer & Schonert-Reichl, 1992) reject the view that the terms storm and stress define adolescence, there is nonetheless unanimous agreement among theorists and practitioners that adolescence entails directly observable changes not only within the biological system of the individual, but also in terms of maturity in the cognitive and psychosocial functioning of the child (Eccles, Wigfield, & Byrnes, 2003). As the child progresses into adulthood, the transition through adolescence is inevitable and the rapid evolution and intensity of the process is inferred to be overwhelming resulting in adolescent stress (Byrne, Davenport & Mazanov, 2007).

Stress can be defined as a condition experienced when an individual perceives demands exceeding available personal and social resources (Lazarus, 1993). Thus, stress stems from some internal and/or external demand that exceeds one’s coping capacity.

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1.1.2

THE TRANSACTIONAL MODEL OF STRESS AND COPING

The transactional model of stress and coping is the most theoretically influential psychological stress and coping theory, and is sometimes referred to as the cognitive-relational approach model (Lazarus & Folkman, 1984). It views stress as a relationship or transaction between individuals and their environment; the nature of this transaction is dynamic wherein stress is the resultant psychological and emotional states that are internally represented as part of the transaction process (Lazarus, 1993).

Harm

Stressor

Primary Appraisal

Threat Challenge

Secondary Appraisal

Coping

Loss

Figure 1: Transactional model of stress and coping

It is understood that the two key processes in dealing with a stressful situation are appraisal - the subjective evaluation of threat- and coping which can be explained in terms of the subjective evaluation of available skills and resources to cope with the stressful situation (Figure 1) (Compas, ConnorSmith, Saltzman, Thomsen, & Wadsworth, 2001; Lazarus, 1993; Smith, Haynes, Lazarus, & Pope, 1993). In the model, appraisals can be of two types: primary and secondary.

Section II-Depression 24


PRIMARY APPRAISAL

Primary appraisal is the first stage of the appraisal process where stressors are evaluated in terms of perceived risks, based on individual differences because the nature of what is considered as stressful is specific and subjective (Park & Folkman, 1997). The interpretation of an event by an individual is hypothesised to be modulated by existing beliefs which are enduring and are based on core assumptions such as self-worth and life experiences, whilst the process of meaning or attribution will occur only when an individual’s set of beliefs or cognitions interact with a given situation (Park & Folkman, 1997; Perrewé & Zellars, 1999). Primary appraisals can be summarised as evaluations of physical and/or cognitive demands (e.g., “Is there a threat to my well-being?”) and these can be of three types: irrelevant, benign-positive, and stressful (Tomaka, Blascovich, Kelsey, & Leitten, 1993). An irrelevant appraisal is one that has no positive or negative ramification whereas a benign-positive appraisal is construed as positive as its consequences on the individual are associated with pleasurable emotions such as love, joy, or peacefulness. Stressful appraisals include harm or loss, threat, and challenge. A stressful appraisal is considered harmful when it involves some loss due to damage sustained in the individual’s self- or socialesteem. Stressful threat appraisals are dependent on past harm or loss experiences, where the individual anticipates future harm or loss. Hence, threat is always associated with harm or loss since both are perceived as having possible negative ramifications. Thus, in threat appraisals, negative



feelings of fear, anxiety, and anger are common. Challenging stressful appraisals focus mainly on potential for gain as outcomes of the situation. They have been associated with a lesser subjective stress and negative emotion in comparison to threat appraisals, but are related to situations that propound demands within a person’s resources or abilities. Several studies have indicated threat and challenge appraisals to affect and predict emotional, behavioural, and physiological responses in potentially stressful situations (Tomaka et al., 1993).

SECONDARY APPRAISAL

Once an event has been identified as potentially stressful, the subsequent secondary appraisal process is then engaged. It involves evaluating whether the potential harm can be altered, avoided or prevented, where to assign blame or credit, and what are the future expectations (Park & Folkman, 1997). Secondary appraisal thus addresses what an individual can do about a stressful situation by evaluating personal resources required for dealing effectively with the demands emanating from the stressful appraisal, and the extent to which these are expected to function favourably to deal with the situation. In this process of secondary appraisal, the individual is concerned with skills, perceived control, and resources to deal with the stressful situation (Lazarus & Folkman, 1984).



1.1.3

COPING

Following the appraisals processes, the individual engages into the coping process which is defined as the cognitive and behavioural efforts to manage the internal and external demands of the person’s environment and resources (Folkman, Lazarus, Dunkel-Schetter, DeLongis, & Gruen, 1986). Coping is thus the main method by which incongruence between global7 and situational8 meanings is managed (Park & Folkman, 1997). In the coping process of the transactional model, actions or ways of coping are assessed and modulated by past coping experience, personality, personal resources which include giving personal interpretation to the stressful situation.

Coping encompasses two basic dimensions: emotion-focused and problem-focused coping (Park & Folkman, 1997). On one hand, emotionfocused strategies specifically target emotions in order to reduce negative affect or distress associated with the stressful situation.

Expressing

emotions, positive reappraisals, acceptance, denial, and seeking sympathy or understanding are examples of emotion-focused coping efforts.

On the

other hand, problem-focused coping targets the problem or situation in order to alter the source of stress. Active coping, planning, direct problem-solving and seeking information or guidance are examples of problem-focused efforts (Park & Folkman, 1997). There has been some criticism that these two dimensional approaches to coping are restrictive in the sense that they

7 8

Global meaning refers to the individual’s general interpretation of situations. Situational meaning refers to appraisals related to a specific situation. Section II-Depression 27


do not include the various coping patterns of the individual i.e. coping effort, coping style and coping resources (Coyne & Gottlieb, 1996). Research has established that different stressors elicit different coping styles and coping strategies, for instance stressors perceived as controllable tend to elicit more problem-focused and approach-oriented coping, while those perceived as uncontrollable elicit emotion-focused and avoidant strategies (Compas, Banez, Malcarne, & Worsham, 1991).

1.1.4

MEASUREMENT OF STRESS

Measurement of stress elicited controversy in adult populations and among adolescents because of the difference in methodology between the use of self-report questionnaires and interview approach (Grant, Compas, Thurm, McMahon, & Gipson, 2004). Although there is some enticement for empirical and situational foci of the interview methodology, this approach nonetheless takes time and requires trained interviewers which render the assessment procedure impractical for large samples. Moreover, interview methods lack anonymity which may result in biases both from interviewer and respondent (Grant et al., 2004). Self-report measures seem thus an a priori method of choice in measuring stress as the latter is construed as being a subjective experience which is in line with the transactional model of stress (Monroe & Kelly, 1995).



MEASUREMENT OF APPRAISAL

Appraisals are commonly measured by two types of subjective selfreports. First, single-item questionnaires are designed to assess primary and secondary appraisals of specific stressors. Administration of these questions usually follows exposure to a stressful situation which makes this method suitable for experimental research. The single-item approach, somewhat inferior in psychometric properties in terms of reliability, does provide excellent preliminary exploration of appraisals related to a particular stressor by enabling researchers to formulate items to measure primary and secondary appraisals fitting the theoretical framework of their study (Herbert & Cohen, 1996). Second, multiple-item appraisal scales in general assess cognitive evaluations of global life stressors (Monroe & Kelley, 1995). The Perceived Stress Scale9 (PSS; Cohen, Kamarck, & Mermelstein, 1983) is an example of a global measure that requires respondents to indicate how unpredictable, uncontrollable and over-loading they perceive their life situation. This measure has adequate psychometric qualities and has been extensively used in laboratory and field research (Monroe & Kelley, 1995). It is for such reasons that the PSS has been utilised in the current study to evaluate the relative contribution of the appraisal dimension of stress in the prediction of depression scores. The psychometric qualities of the PSS are further detailed in Chapter Five of this dissertation.

9

See Appendix C Section II-Depression 29


MEASUREMENT OF COPING

Factor analytic research on coping has established that the two-factor model, i.e. problem-focus and emotion-focus, proposed by the transactional model does not provide adequate fit (Coyne & Gottlieb, 1996).

Coping

responses have been found to yield three and sometimes four factors, depending on the studies. For example, Walker, Smith, Garber, and Van Slyke (1997) identified three factors: active coping (problem solving, seeking support,

self-isolation),

passive

coping

(self-isolation,

behavioural

disengagement, and acceptance), and accommodative coping (acceptance, distract-ignore, and self-encouragement). Yet in another study, four factors were identified: active coping, social support (emotion-focused and problemfocused support), distraction (behavioural action and physical release of energy) and avoidance (cognitive and behavioural avoidance) (Ayers, Sandler, West & Roosa, 1996).

The Coping Inventory for Stressful Situations10 (CISS; Endler & Parker, 1990) is one such self-report measure that was initially developed out of the transactional theoretical framework. It consists of items measuring emotionfocused and problem-solving approaches to coping but it also includes the other dimension found in empirical studies, namely avoidance coping which evaluates changes aimed at avoiding the stressful situation via distraction as a means to alleviating stress levels.

Emotional reactions that are self-

10

See Appendix D Section II-Depression 30


oriented are assessed by the emotion-focused coping subscale. Its aim is to assess the person’s capacity to reduce stress through emotional responses, and self-preoccupation. The problem-solving dimension is measured on the CISS by the task-oriented subscale which evaluates purposeful task-oriented efforts aimed at solving the problem through cognitive restructuring to alter the perception on the stressful situation. Further detail on the psychometric properties of the CISS is provided also in Chapter Five as this measure has been utilised in the current study.

1.1.5

COMMON STRESSORS IN CHILDHOOD & ADOLESCENCE

Stressors that have been identified in children commonly occur at school, within the family unit, the self, and social contexts (Dise-Lewis, 1988; Halstead, Johnson, & Cunningham, 1993).

Given the developmental

processes involved pertaining to identity formation, evolving interpersonal relationships, and changing social roles in adolescence, consequently, the experience of stress in this age-group has been categorised into eight broad domains (Seiffge-Krenke, 1995): the self, which includes feeling lonely, being humiliated, and being dissatisfied with one’s appearance; parental relationship; romantic relations; social relations, difficulties at school, for example getting a bad grade; politics and economic future; critical life events, such as death of a significant person; and idiosyncratic events such as illnesses.



1.1.6

GENDER DIFFERENCES IN ADOLESCENT STRESS AND COPING

Adolescence is considered to be a period of vulnerability because stressful life events that occur therein are considered to be risk factors for the onset and exacerbation of depressive and anxious psychopathologies (Compas, Orosan, & Grant, 1993; Daley et al., 1997). Although both males and females are exposed to a number of stressors during adolescence, the types of stressors appraised differ from one gender to the other (Hankin & Abramson, 2001, 2002). For example, adolescent girls rate interpersonal relationship strains higher whilst adolescent boys appraise as more stressful non-interpersonal situations related to academic performance and schooling. Such differences in perceived stressful life events have been postulated to partly explain the differences between males and females in the presentation of depression and anxiety in adolescence and adulthood (Hankin & Abramson, 2001; Hankin et al., 1998).

Apart from appraisals, gender differences among adolescents have also been found in coping strategies. In active problem-solving strategies to manage stress, adolescent girls have a greater tendency to use social support, seek advice and sympathy, and talk more openly about their problems while adolescent boys, more often have been found to make use of humour and physical recreation (Chapman & Mullis, 1999; Frydenberg & Lewis, 1991). Similarly, in emotion-focused coping strategies, girls use more ruminative strategies such as worry, and expect more negative consequences (Seiffge-



Krenke, 1995) while boys make greater use of distraction and avoidance (Frydenberg & Lewis, 1993).

The differences in appraisal and coping styles have been partially explained by the fact that boys and girls are conditioned to use genderappropriate methods to manage emotions when under stress (Compas, Orosan, & Grant, 1993). Males are typically discouraged from displaying emotions while females often receive attention and consolation for emotional display.

Moreover, males are encouraged to be active and

independent problem-solvers, whereas females learn to seek comfort in interpersonal relationships. These differences in social conditioning influence a child’s repertoire of coping skills and may explain the commonly observed gender differences in coping behaviour between males and females in adolescence and adulthood (Nolen-Hoeksema, Larson, & Grayson, 1999).

1.1.7

ADOLESCENT STRESS: CAUSAL ROLE FOR DEPRESSION & ANXIETY

Failure to cope successfully with life stressors in adolescence have been linked to the development of psychiatric symptoms of clinical significance (Grant et al., 2004). The experience of stress has been associated with depression (Garber 2006; Hankin, 2006), suicidal ideation (Diaz et al., 2002), actual risk of suicide (Eaton et al., 2008), and anxiety (Inderbitzen & Hope, 1995; Yarcheski & Mahon, 2000). Avoidant coping strategies have been found to be precursor to the use of aggression, alcohol or other substances (Compas et al., 1993; Seiffge-Krenke, 1995). Section II-Depression 33


Stress can be chronic or acute. Alongside severity of a stressor, it is important to consider both its onset and its course as stress can both precede and be a consequence of depression (Hankin & Abramson, 2001).

For

instance, adolescents who develop depression have significantly greater number of severe stressors when compared to those who are not depressed (Williamson et al., 1998).

The type of stressor also appears to play a significant role in the development of depression and anxiety for example, interpersonal stressful life events such as changes in social relationships or loss of significant relationships have been strongly associated with increased risk of depression and anxiety in adolescents, and such risks are more common in females (Rudolph, 2002). Moreover, research demonstrated parents’ stressful life events play a critical role in the risk of increasing an adolescent’s stress levels, which in turn render the adolescent vulnerable to the development of depression and anxiety (Adrian & Hammen, 1993; Grant & Compas, 1995; Hammen, 2006).

As stress has been found to be closely associated with depression and anxiety in adolescents, the following two sections of this chapter will attempt to encapsulate some important aspects of these two psychopathologies with particular reference to adolescents.



SECTION TWO: DEPRESSION

1.2.1

DEFINITION OF DEPRESSION

In current psychology and psychiatry literature, the term depression is interchangeably used to describe a psychiatric illness or a plethora of depressive symptoms which generally refer to a mood that predominantly encompasses lack of positive affect, and feelings of sadness experienced by individuals (Reinemann & Swearer, 2005). In the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM 5; APA, 2013) which is used by mental healthcare professionals to define and diagnose psychiatric illnesses, the term depression is used to imply a psychiatric illness with a number of depressive symptoms with substantial duration impacting negatively on the life of the individual (APA, 2013).

Depressive disorders are thus grouped into four main diagnostic categories by the current DSM, based on symptom expression, severity, and duration. The first, disruptive mood dysregulation disorder11 refers to the presentation of persistent irritability and frequent episodes of extreme behavioural dyscontrol in children up to 12 years of age. Second, Major Depressive Disorder (MDD)12 is characterised by the presence of at least five of the nine despondent symptoms present for at least a two-week period and 11 12

See Appendix E See Appendix F 35


which cause significant distress in social and or occupational functioning of the individual. Third, Persistent Depressive Disorder13 formerly known as Dysthymic

Disorder

requires

fewer

despondent

symptoms

and

is

characterised by at least two years of depressed mood for more days than not, accompanied by additional depressive symptoms that do not meet the criteria for MDD. Fourth, premenstrual dysphoric disorder14 concerns women and pubescent girls and is characterised by mood lability, irritability, dysphoria, and anxiety symptoms that occur repeatedly during the premenstrual phase of the cycle and remit around the onset of menses or shortly thereafter. Symptoms must have occurred in most of the menstrual cycles during the precedent year and must have an adverse effect on work or social functioning.

Other DSM criteria for which symptoms of depression are observed but fail to meet any of the four abovementioned specific diagnoses can be classified according to any one of the following labels: Substance/MedicationInduced Depressive Disorder, Depressive Disorder Due to another Medical Condition, Other Specified Depressive Disorder, Unspecified Depressive Disorder (APA, 2013).

It is worth mentioning that in the previous version of the DSM (APA, 2000), Depressive Disorders alongside Bipolar Disorders were under the Mood Disorders category, but in the current DSM, this category was removed 13 14

See Appendix G See Appendix H Section II-Depression 36


and thus Bipolar and related disorders are now in a separate chapter. Depressive disorders can be distinguished from Bipolar Disorders in that the former do not entail hypomania, and/or mania.

Because Depressive

Disorders are without mania, they are sometimes referred to as unipolar as the mood remains at one emotional state or "pole" (APA, 2013).

1.2.2

DEPRESSIVE DISORDERS IN ADOLESCENTS

In adolescents, depression consists also of the behavioural, somatic, motivational and cognitive characteristics observed in depressed adults however, depressed mood may not necessarily occur. Instead, chronic and incessant irritability may characterise the adolescent with depression. Weight gain may be less relevant in this age group as it can be part of normal physical development however, rapid and extreme shifts in weight can be diagnostically relevant. For a diagnosis of Persistent Depressive Disorder in adolescents, the symptoms need only be present for one year and similar to adults, the symptoms cannot remit for more than a two-month period (APA, 2013).

1.2.3

PREVALENCE OF DEPRESSION IN ADOLESCENTS

It is estimated that 340 million people suffer from depression worldwide at any given time and by 2030 unipolar depression will become the prime cause global burden of disease15. The economic outlay related to depression

15

It is a measure of disability based on estimates of years of life lost due to premature death, as well as years of healthy life lost due to disability from disease and injury. Section II-Depression 37


in adolescents is unknown but is likely to be considerable due to its impact on healthcare services, schools, child agencies, and families.

In adults, lifetime prevalence rates for depression are estimated to be between 15% and 22% whilst lifetime prevalence rates in childhood (age 8 to 12 years) are estimated to be around 3% (Costello, Mustillo, Erkanli, Keeler, & Angold, 2003). The rate in early adolescence climbs slightly and continues to increase through late adolescence to reach up to 17% (Birmaher, Ryan, Williamson, Brent & Kaufman, 1996).

Despite the high prevalence of

depression among adolescents, many remain undiagnosed and thus untreated (Wells, Kataoka, & Asarnow, 2001). The mean age for the onset of depression in adolescents is between 14 and 15 years of age, and the mean duration of an episode approximates 26 weeks (Lewinsohn, Clarke, Seeley, & Rohde, 1994). Depression is considered pervasive and disabling because depressed adolescents grow up to be depressed adults (Weismann et al., 1999). Adolescents who experience a depressive episode are 2 to 7 times more likely to experience a depressive episode in adulthood compared to non-depressed adolescents (Rutter, Kim-Cohen, & Maughan, 2006).

1.2.4

GENDER DIFFERENCES IN ADOLESCENT DEPRESSION

In children, the ratio for depression is similar for boys and girls but, in early adolescence (around the age of 13), the rate of depression has been found to increase for girls (Costello et al., 2003). This rate actually doubles for girls as from the age of 15 (Hankin et al., 1998), which is consistent with Section II-Depression 38


epidemiological data which estimates the prevalence of depression to be twice as much in adult women than in adult men (Nolen-Hoeksema, 2001).

Differences across gender in the clinical presentation of depressive symptoms have been observed (Joiner & Blalock, 1995; Joiner Blalock, & Wagner, 1999). Girls are more likely to report higher levels of somatic complaints (e.g., weight or appetite disturbance; sleep problems; concentration difficulties; fatigue), cognitive (e.g., low self-worth), and affective symptoms (e.g., sadness or depressed mood).

These gender

differences have been found to persist throughout adolescence, and continue into adulthood and across lifespan (Bennett, Ambrosini, Kudes, Metz, & Rabinovich, 2005).

1.2.5

THEORIES OF DEPRESSION

With psychology becoming a specialised discipline budding from mainstream philosophy over the past century, many theories of psychopathology have emerged offering aetiological explanations for depression. The nature, cause, and maintenance of depression in children and adolescents have been viewed from a wide range of theoretical perspectives including psychodynamic, behavioural, cognitive, interpersonal, biological, and environmental models that vary in their comprehensiveness and in their level of empirical support. An in-depth review of all these perspectives will be outside the scope of this dissertation instead, salient features of the biological perspective will be briefly outlined followed by the Section II-Depression 39


behavioural and cognitive approaches because the tendency in clinical practice has been to address and treat depression within both a biological and a cognitive-behavioural paradigm simultaneously.

THE BIOLOGICAL PERSPECTIVE

From a biological approach, the despondent mood adolescents endure can be explained partly by the bodily changes they go through during this period. Even though the direct effects of changes in behaviour are attributed to neurotransmitters and sex hormones, debate about their actual psychological impact still exists (Walsh, 2000). Two biological theories which have been supported by neurobiological research will be briefly outlined in the following paragraphs.

THE HYPOTHALAMUS-PITUITARY AXIS

Part of the biological explanation for depression has been related to an over-stimulated neuro-chemical stress system, and particular emphasis has been laid upon the hypothalamic-pituitary-adrenal (HPA) axis dysfunction (Nemeroff, 1998). The hypothalamus is responsible for releasing the stress hormone corticotrophic-releasing hormone (CRH) when the brain assesses a potential threat or psychological distress. The anterior pituitary gland is then stimulated to release adrenocorticotrophic hormone (ACTH) which in turn makes the adrenal glands secrete the hormone cortisol in the bloodstream. The hypothalamus monitors blood level cortisol and when the latter rises, the



hypothalamus slows down its influence on the pituitary gland by reducing its production of CRH.

Similarly, when blood level cortisol is reduced, the

hypothalamus causes the pituitary gland to produce more ACTH (Figure 2) under stress.

In individuals with depression, the hypothalamus may

continuously influence the pituitary gland to produce ACTH irrespective of blood level cortisol. Although such a neurobiological dysfunctional response to stress has been found in adult populations, this pattern has been partially supported in child and adolescent research (Rao, Hammen, & Poland, 2010).

Figure 2: The HPA system

THE PREFRONTAL CORTEX

The other prevailing biological explanation for depression in adolescents consists of the late maturation of the prefrontal cortex (PFC), the brain structure responsible for regulating emotions, planning, reasoning and selfcontrol. This explanation is consistent with the hypothesis of an integrated Section II-Depression 41


neurobiological model of depression known as the limbic-cortical network model (Mayberg, 2003) which explains depression in terms of increased activity in limbic regions in conjunction with decreased PFC activity. Brain imaging technology provided evidence for a smaller ventromedial cortex, which forms part of the PFC, in individuals affected by depression. One of the functions of the ventromedial cortex is to enable a person to switch from one mood to another mood, as well as to experience pleasure and positive reinforcement (i.e. rewards). The ventromedial cortex of depressed people is smaller due to a reduction in the number of glial cells in that area. Glial cells primarily supply neurones with energy and a reduction in the number of glial cells in parts of the brain is associated with a decline in neuronal activity. As the PFC regulates emotions, and more specifically, inhibits inappropriate or incapacitating emotions, then a less active PFC due to a decrease in glial cells is inferred to induce negative emotions, such as depressed mood. Drastic changes in neurotransmitters dopamine and serotonin, both responsible for emotional stimuli in the limbic system of the brain, occur during adolescence.

These have been found to cause the individual to

simultaneously experience a heightened sensitivity for stress and a lowered susceptibility for rewards.

It is thus further hypothesised that the

combination of a PFC that is not yet completely developed and endocrinal changes may be responsible for the experience of despondent mood in adolescents.

For some adolescents, these will be enacted through

internalising or externalising problem behaviours (Walsh, 2000). This model is also consistent with literature reviews which propose a dysfunctional Section II-Depression 42


limbic-cortical network in bipolar disorders because of decreased prefrontal modulation and overactive limbic structures (Strakowski, DelBello, & Adler, 2005).

THE BEHAVIOURAL PARADIGM

Apart from biological theories, behaviourism 16 explains depression in terms of an operant conditioning paradigm. According to Lewinsohn and Graf (1973), depression is caused by a combination of stressors present in an individual's environment and a lack of personal skills to deal effectively with the resulting psychological stress. In other words, an individual becomes depressed due to lack of skills to cope with emerging life stressors. This behavioural approach to depression was based on a classical animal study in which dogs were given electric shocks to their feet (Seligman & Maier, 1967). In the control condition, the dogs were allowed to jump over a small barrier and escape the electric shocks, but in the experimental condition the barrier was higher and the foot shocks were therefore inescapable. In the follow up trial, dogs that could not escape in the first part of the study made no attempt to escape the shocks even when they were given the opportunity to do so, in effect they had learned to become helpless. The similarity between learned helplessness and some of the symptoms of human depression whereby patients become passive and accepting of their situation

16

Behaviourism is a theory of learning based upon the premise that behaviours are responses acquired through conditioning which occurs through repetitive interaction with environmental stimuli. Section II-Depression 43


and make little or no attempt to resolve their problems led to the learned helplessness theory.

Although this behavioural paradigm is useful for explaining the process by which some individuals become depressed, the learned helplessness theory could neither account for nor explain why many others do not become depressed even after experiencing many unpleasant life events. Moreover this theory does not take into consideration the varying degree of severity of depressive symptoms nor the varying reactions to situations that may or may not necessarily cause learned helplessness and clinical depression (Cole & Coyne, 1977; Hiroto & Seligman, 1975; Peterson & Park, 1998).

Classical behaviourism focuses exclusively on external and directly observable and measurable behaviour. This approach to the understanding of depression was considered extreme and quickly became redundant because thought processes, integral to the modulation of behaviours, were not taken into consideration. Later, Seligman (1975) modified this theory to incorporate thinking style as a factor also determining learned helplessness. He suggested that depressed individuals have a tendency to use a more pessimistic explanatory style when thinking about stressful events than nondepressed individuals who are believed to be more optimistic in nature. Seligman is thus often seen as the link between behaviourists and cognitive theorists because of the inclusion of cognitions in the original behavioural learned helplessness theory for explaining depression.



THE HOPELESSNESS THEORY OF DEPRESSION

The inclusion of thought processes in the classical behaviourist paradigm led to the cognitive hopelessness theory of depression (Abramson, Metalsky, & Alloy, 1989). According to this theory, any negative experience in life is perceived by the individual through three types of attributions: internal or external locus of control, pervasiveness of the negative thinking style, and generalisation of the negative thinking pattern. In other words, an individual with a tendency towards depression, will attribute negative life events to stable (likely to persist over time) and global (likely to affect many areas of life) causes, and will infer that the occurrence of a negative event is a direct consequence of personal flaws. The expectation is therefore that desired outcomes will not occur or that aversive outcomes will occur and that one cannot change this situation is a proximal sufficient cause for the development of symptoms of depression. Thus, the feelings of worthlessness and helplessness that are triggered render the individual vulnerable to developing episodes of depression when faced with negative life events.

AARON BECK’S COGNITIVE TRIAD

Whereas Seligman’s learned helplessness theory emerged from animal studies, and the modified subsequent version, the hopelessness theory integrated a cognitive twist, a related cognitive approach proposed by Beck (1976) emerged from empirical observations of depressed patients’ descriptions of their thought content through verbalisation. According to Section II-Depression 45


Beck, depressed individuals nurture negative spontaneous or automatic thoughts which relate to the self, the world and the future, hence the negative cognitive triad.

It is postulated that individuals suffering from

depression tend to see themselves as inadequate, see the world with obstacles and difficulties and foresee problems persisting into the future. When such negative automatic thoughts come to mind, feelings of misery and despair, and depressive behaviour such as procrastination and inactivity are triggered to the point of hopelessness and suicidal ideation.

Beck considers automatic thoughts as schemas which are believed to be relatively enduring characteristics of a person’s cognitive representation of the self and the views on life in general. When an individual is faced with any given situation, the schema most relevant to the situation is activated which subsequently influences how the individual perceives, encodes, and retrieves information regarding that particular situation.

Beck hypothesises that

depressogenic schemas are typically organised as sets of dysfunctional attitudes such as “If I fail at my work then I am a failure as a person.” Such depressogenic schemas are believed to trigger a pattern of negatively biased, self-referent information processing that would eventually lead to the onset of depressive symptoms. Negative biases maintain the beliefs in the validity of the negative thoughts despite the presence of contradictory evidence. Biases generally include arbitrary inference, selective abstraction, overgeneralisation,



magnification and minimisation, personalisation and dichotomous thinking (Beck, 1972). Each of these terms will be briefly explained. Arbitrary inference is similar to jumping to negative conclusions that may not be justified by evidence whilst selective abstraction consists of focusing on a negative detail taken out of context, ignoring the more salient features of the situation and conceptualising the whole experience on the basis of this detail. Overgeneralisation refers to a pattern of drawing a general rule or conclusion on the basis of one or more isolated incidents and applying the concept across the board to related and unrelated situations. Magnification and minimisation are reflected in errors in evaluating the significance or magnitude of an event such that it constitutes a distortion. Personalisation refers to the tendency to relate external events to oneself when there is no basis for making such a connection. And finally, dichotomous thinking is the tendency to put all experiences in one of two opposite categories; for example, perfect or defective, smart or stupid, such that in describing oneself, the individual selects the extreme negative categorisation (Beck, 1972).

1.2.6

EMPIRICAL STUDIES ON COGNITIVE MODELS

Strong support for the negative cognitive triad has been found in research whereby individuals who perceive themselves as not competent, who maintain negative beliefs about the self, world, and future, and who make stable and global attributions for their failure in lives, have an increased Section II-Depression 47


likelihood of developing depressive symptoms (Bruce et al., 2006; Haaga, Dyck, & Ernst, 1991). Studies using adolescent samples have also provided support for the applicability of both Beck’s cognitive theory (Abela & Sullivan, 2003; Joiner, Metalsky, Lew, & Klocek, 1999) and the hopelessness theory (Abela & Hankin, 2008).

Adolescents with high levels of dysfunctional

attitudes (Abela & Skitch, 2007; Hankin, Wetter, Cheely, & Oppenheimer, 2008) or a negative cognitive style (Abela, McGirr, & Skitch, 2007; Gladstone, Kaslow, Seeley, & Lewinsohn, 1997) are more likely to experience increases in depressive symptoms following stressful episodes.

In addition, onset of

clinical depression has been predicted by negative events interacting with dysfunctional attitudes (Lewinsohn, Joiner, & Rohde, 2001) and negative cognitive styles (Bohon, Stice, Burton, Fudell, & Nolen-Hoeksema, 2008).

1.2.7

DIATHESIS-STRESS MODELS

Cognitive models imply that people have, to varying degrees, cognitive vulnerabilities or diatheses for developing depression (Ingram & Luxton, 2005). Cognitive theories of depression are often referred to as cognitive diathesis-stress models because the premise is that cognitive diathesis and stress are the two necessary factors for the development of depression. From these diathesis-stress models, it is implied that psychopathology is complex and multifaceted suggesting a number of interacting factors that lead to its development.



The challenge with diathesis-stress models is that it is hard to ascertain whether negative cognitions are the resultant of depressive symptoms or the cause. The interaction of negative cognitions, particularly attributional style and stress has predicted depressive symptoms (Hilsman & Garber, 1995) whilst others have partially supported such interaction (Conley, Haines, Hilt, & Metalsky, 2001; Lewinsohn, Allen, Seeley, & Gotlib, 1999; Lewinsohn, Joiner, & Rohde, 2001; Nolen-Hoeksema, Girgus, & Seligman, 1992). Other studies have failed to show that a depressive inferential style about self, future, or causes, or negative beliefs about the self or future predict depressive symptoms or diagnoses (Abela & Sarin, 2002; Bennett & Bates, 1995; Hammen, Adrian, & Hiroto, 1988).

According to developmental researchers, there has been no support for cognitive diathesis–stress models in children because attributional style is believed to emerge as a vulnerability factor for depression only when children develop abstract reasoning and formal operational thinking during the transition from late childhood to early adolescence (Gibb & Alloy, 2006). Cognitive diatheses seem to be therefore related to maturity (NolenHoeksema et al., 1992; Weisz, Southam-Gero, & McCarty, 2001).

1.2.8

MEASURES OF DEPRESSION

Biological, behavioural and cognitive theories of depression empirically support and fundamentally inform clinical practice. The application of these theories in the assessment and treatment of depression has led to an Section II-Depression 49


integrated developmental biopsychosocial understanding of depression for children and adolescents where the developmental level, internal and external factors associated with depression, and the interplay of these factors are crucial elements to the understanding and management of depression (Hammen & Rudolph, 2003). These theories have been at the basis of the development of measures of depression such as the Beck Depression Inventory–II 17 (BDI-II; Beck, Steer, & Brown, 1996) and the Multiscore Depression Inventory for Children18 (MDIC; Berndt & Kaiser, 1996). These two measures are empirically derived and used internationally across clinical and non-clinical settings.

The BDI-II is an immensely popular and psychometrically sound selfreport instrument for the assessment of the severity of depressive symptoms in adults and adolescents as young as the age of 13 (Dozois, Dobson, & Ahnberg, 1998). The items consist of definitions of symptoms that address DSM criteria for depression such as agitation, concentration difficulty, and feelings of worthlessness. The MDIC is another self-report questionnaire measuring severity of depression based on dichotomous “true” or “false” responses. The MDIC provides measures of different features of depression such as low energy level, low self esteem, social introversion, pessimism, irritability, sad mood, and instrumental helplessness. Further information on the MDIC and the BDI-II will be provided in Chapter Four and Chapter Five respectively as these measures have been used in the current research. 17

See Appendix I See Appendix J for the French version.

18



It has already been underscored in the first section of this chapter that stress is strongly related to depression and anxiety; the aim of this second section has been to denote some salient features of depression with particular reference to adolescents. The following section will provide a brief overview on anxiety in adolescents and the interplay between depression and anxiety will be elaborated in the final section of this chapter.



SECTION THREE: ANXIETY

In psychology, anxiety is a well-documented dimension which underwent substantial fine tuning over the last decades with regard to its conceptual definitions, mechanisms, effects, and assessment.

Anxiety has been

mentioned in psychological literature since the beginning of the 20th century, notwithstanding being mentioned in philosophical writings since Ancient Greece (Akiskal, 2008). With psychology growing into a scientific field last century, the empirical study of anxiety sprawled in the 1950s with the development of Mrs. Taylor’s Manifest Anxiety Scale (Taylor, 1953) which provided research psychologists with new assessment possibilities of this dimension, albeit difficulties and ambiguities in its conceptualisation at the time.

1.3.1 DEFINITION OF ANXIETY

Today, it is widely accepted that anxiety refers to a basic emotion characterised by physiological (e.g. heart rate, muscular tension, and dizziness), behavioural (e.g. avoidance or emotional reactivity) and psychological (e.g. worried thoughts) symptoms. Anxiety is present as from infancy, with its expressions falling onto a continuum from mild to severe. Anxiety per se is not typically maladaptive but one frequent and established conceptualisation is that anxiety becomes pathological when it interferes 52


with an individual’s normal functioning because the symptoms have become overly frequent, severe, and persistent (APA, 2013). Thus, anxiety disorders at any age are characterised by persisting or extensive degrees of anxiety and avoidance associated with subjective distress or impairment.

1.3.2 ANXIETY DISORDERS IN CHILDREN AND ADOLESCENTS

Anxiety disorders represent 31.9% of psychiatric disorders in adolescents, followed by behavioural disorders (19.1%), depressive disorders (14.3%), and substance use disorders (11.4%) (Merikangas et al., 2010). The median age of onset for diagnostic criteria is at 6 years for anxiety, at 11 years for behavioural disorders, 13 years for unipolar depression, and 15 years for substance use disorders (Costello, Foley & Angold, 2006). Prevalence of anxiety symptoms, such as worries and fears, has been estimated to be as high as 69% among children (Spence, 1997) whereas prevalence of anxiety disorders varies between 1% and 20.3% in adolescent community samples. Estimates of anxiety disorders in clinical samples can reach up to 76% (Costello et al., 2003).

1.3.3 DIAGNOSTIC CATEGORIES OF ANXIETY DISORDERS

The current DSM recognises approximately seven types of anxiety disorders namely separation anxiety disorder (SAD), selective mutism, specific phobia, social phobia, panic disorder (PD), agoraphobia, and generalised anxiety disorder (GAD).

Two of these specifically affect children and Section III- Anxiety 53


adolescents; SAD and selective mutism.

All seven disorders share the

characteristics of anxiety being enduring and excessively difficult to control with negative impact on the individual’s normal functioning (Albano, Chorpita, & Barlow, 2003). The following paragraphs will highlight the main criteria to meet the diagnosis of each of the seven DSM anxiety disorders present in children and adolescents.

As aforementioned, SAD is a disorder specific to children and adolescents characterised by persistent anxiety and fearfulness - developmentally inappropriate - related to separation from home or significant individuals in the life of the child. The symptoms may include thought of events that could lead to loss of or separation from attachment figures and reluctance to go away from attachment figures, as well as nightmares and physical symptoms of distress. Although the symptoms often develop in childhood, they can be expressed throughout adulthood as well. The duration of the disorder must be at least four weeks and onset must occur before the age of 18. Prevalence estimates are approximately 7.6% in US children and generally decrease as children age (APA, 2000).

Selective mutism is characterised by a consistent failure to speak in social situations in which there is an expectation to speak (e.g., school) even though the individual may speak in other situations. Failure to speak has significant consequences on achievement in academic or occupational settings and interferes with normal social communication. Selective mutism is estimated Section III- Anxiety 54


to affect less than 1% of US children (Bergman, Piacentini, & McKracken, 2002).

Social Phobia, also known as Social Anxiety Disorder, is characterised by a persistent fear of social or performance situation in which embarrassment may occur. In children, there needs to be evidence for age-appropriate social relationships and anxiety must occur in peer settings, not just with adults. Exposure to the feared social situation provokes anxiety, which may be crying, tantrums, freezing, or isolation from social situations. Adolescents may perceive the fear as unreasonable, but this may be absent in children. The social situation is usually avoided or experienced with intense fear. Avoidance or distress should interfere with the person’s normal routine or functioning. For children under the age of 18, the duration must be for a minimum of 6 months. Social Phobia has been estimated to affect 9.1% of U.S adolescents (APA, 2013).

Panic Disorder (PD) is characterised by the presence of recurrent, unexpected panic attacks 19 followed by a minimum of one month of excessive concern about having another attack, worry about consequences of the attack such as suffocation or heart failure. The criteria for a panic attack is a period of intense fear or discomfort in which at least four of the following symptoms suddenly onset and peak within 10 minutes: heart palpitations or

19

Panic attacks are abrupt surges of intense fear or intense discomfort that reaches a peak within minutes, accompanied by physical and/or cognitive symptoms such as rapid heartbeat, hyperventilation and thoughts of having a heart attack. Section III- Anxiety 55


accelerated heart rate; sweating; trembling or shaking; sensations of shortness of breath; feelings of choking; chest pain; nausea or abdominal discomfort; dizziness; being detached from reality or oneself; fear of losing control; fear of dying; numbness or tingling sensations; and chills or hot flashes. PD is usually characterised with or without agoraphobia and is estimated to affect 2.3% of US adolescents (APA, 2013).

Specific Phobia is the persistent irrational fear regarding the presence or anticipation of a specific object or situation. Exposure to the object or situation provokes an anxiety response, which may take the form of a panic attack. In children, the anxiety response may be crying, tantrums, freezing, or clinging. Adults may recognise the fear being unreasonable but children may not be readily alert it.

The phobic stimulus is usually avoided or

associated with intense distress and the avoidance or distress interferes with the individual’s normal routine. Duration must be at least six months for children and adolescents.

The most common types of phobias include

animal, natural environment, blood injection-injury, and situational. Specific phobia is estimated to affect 19.3% of US children and adolescents (APA, 2000).

Individuals with agoraphobia are fearful and anxious about two or more of the following situations: using public transportation; being in open spaces; being in enclosed places; standing in line or being in a crowd; or being outside of the home alone in other situations. The individual fears these Section III- Anxiety 56


situations because of thoughts that escape might be difficult or help might not be available in the event of developing panic-like symptoms or other incapacitating or embarrassing symptoms. These situations almost always induce fear or anxiety and are often avoided and require the presence of a person for reassurance. Agoraphobia is estimated to affect 4.5% of US adolescents (Roberts, Roberts, & Xing, 2007)

Generalised Anxiety Disorder, GAD, is characterised by excessive worry which is difficult to control, and anxiety occurring most days for a duration of at least six months. In addition to excessive worry, children must have only one additional symptom (three are required for adults) that has to be present for more days than not over the preceding 6 months. Associated symptoms for GAD include: restlessness, lack of energy or fatigue, difficulty concentrating, irritability, muscle tension, and sleep disturbance. Anxiety symptoms should result in clinically significant functional distress and other anxiety disorders must be ruled out. In children and adolescents, worries are more related to performance at school, even when they are not being evaluated.

Adolescents with GAD may present as overly conforming,

perfectionist, approval seeking, and may require excessive reassurance. There is some evidence to suggest GAD in children may be over-diagnosed therefore, careful evaluation is required.

It is estimated that 2.2% of

adolescents in the US present with GAD (APA, 2000).

Section III- Anxiety 57


Any other significant anxiety symptoms that fail to meet the criteria of any one of the seven specific anxiety disorders may be given one of the following diagnoses: Substance/Medication-Induced Anxiety Disorder, Anxiety Disorder Due to another Medical Condition, Other Specified Anxiety Disorder, Unspecified Anxiety Disorder (APA, 2013). The previous version of the DSM included Obsessional Compulsive Disorders (OCD) as part of the Anxiety Disorders category but the current version of the DSM has a separate chapter for OCD although the relationship with anxiety is highlighted therein. Similarly Post-Traumatic Stress Disorder (PTSD) and Acute Stress Disorder (ASD) have also been removed from the Anxiety Disorders category to be in a separate chapter related to trauma and stress in the current DSM (APA, 2013).

1.3.4. DIFFERENTIATING PATHOLOGICAL ANXIETY IN YOUTH

For clinical psychologists, drawing the line between normal and pathological anxiety can be particularly complex in children because the latter manifest fears and anxieties as part of normal development. For example, separation anxiety normatively occurs between 12 and 18 months, fears of thunder or lightning between 2 and 6 years, and so forth. Although these phenomena may be acutely distressing, they are typically short-lived, and as such distress per se does not represent an adequate criterion for distinguishing between normal and clinical anxiety states. Another challenge for clinicians is that in the assessment of childhood fears and anxiety, children



have not acquired the cognitive capabilities to communicate information (language skills and cognition, emotions, and avoidance, as well as the associated distress and impairments) necessary to the application of the diagnostic nomenclature.

Thus, developmental differences must be

therefore carefully considered when assessing anxiety before reaching a diagnostic decision.

1.3.5. GENDER DIFFERENCES IN ANXIETY

Most findings suggest that adolescent girls report more anxiety symptoms and are therefore more likely to be diagnosed with anxiety disorders than boys (Albano et al., 2003; Lewinsohn, Gotlib, Lewinsohn, Seeley, & Allen, 1998). This difference was found to emerge as early as the age of 6, with twice as many girls having anxiety disorders compared with boys, even through adolescence the rate at which girls develop anxiety disorders increases much faster than the rate for boys (Lewinsohn et al., 1998).

Nonetheless, for some specific anxiety disorder symptoms for

example, social phobia and social anxiety, preadolescent boys have been found to report more anxiety symptoms than girls (Compton, Nelson, & March, 2000; La Greca & Lopez, 1998; Last & Strauss, 1989).

1.3.6. THEORIES OF ANXIETY

Etiological theories of anxiety are exhaustive and extensive and generally can be grouped into biological theories which focus mainly on Section III- Anxiety 59


neurobiochemicals and endocrine levels, brain structures and genetics. Behavioural theorists tend to emphasise parenting styles and early learning experiences whilst cognitive theorists point out the relevance of beliefs and perceptions for the maintenance of anxiety.

Looking at all these perspectives is beyond the scope of this dissertation instead, the foci will be on two anxiety theories namely the state-trait and behavioural inhibition /behavioural activation systems theories because in the current research, two scales that were developed out of these two theories have been used to measure components of anxiety involved in the development of depressive symptomatology.

THE STATE-TRAIT THEORY OF ANXIETY

With the introduction of empirical research in clinical psychology in the 1950s, when Cattell (1966) applied multivariate and factor analytic techniques, two distinct facets of anxiety emerged. The first factor was termed trait anxiety because it consisted of variables with relatively stable personality characteristics, whilst the second factor was referred to as state anxiety as it consisted of response patterns that fluctuated over time and situation.

Spielberger (1989) elaborated on the findings of Cattell and formulated a theoretical model of state-trait anxiety where a distinction was made between stable and unstable dimensions of anxiety. State anxiety is also hypothesised to involve transient unpleasant feelings of apprehension, Section III- Anxiety 60


tension, nervousness or worry, often accompanied by the activation of the autonomic nervous system which forms a natural defence and adaptation mechanism when confronted with threat (Hankin, Fraley, & Abela, 2005). State anxiety is thus expected to be high in circumstances perceived to be threatening, irrespective of real danger, for example in cases of phobia. Traits refer to inherent enduring and general dispositions that are inherent and which allow the individual to behave in a consistent manner irrespective of situations.

People with high trait anxiety presumably are prone to

experiencing state anxiety, perhaps to excess, because of an inherent tendency to perceive a larger number of situations as threatening.

MEASUREMENT OF STATE AND TRAIT ANXIETY

From the trait theory of anxiety was derived the Manifest Anxiety Scale (MAS; Taylor, 1953) which measures anxiety levels in children. Later, a modified version of the MAS with standardised data was developed and renamed the Children’s Manifest Anxiety Scale (CMAS; Castaneda, McCandless & Palermo, 1956).

Whilst the CMAS was widely used and

published, Reynolds and Richmond (1978) reported therein a number of psychometric flaws which did not at the time meet the American Psychological Association (APA, 1954) guidelines for psychological tests. Therefore, items of the CMAS were modified and reordered and the scale was named the Revised Children’s Manifest Anxiety Scale 20 (RCMAS; Reynolds & Richmond, 1997) as it is now known. Further detail on this 20

See Appendix K Section III- Anxiety 61


instrument is provided in Chapter Four as it was used to establish the convergent validity of the DASS-21 anxiety scale in the current study.

THE BEHAVIOURAL INHIBITION AND ACTIVATION SYSTEMS (BIS-BAS)

The other theory on anxiety relevant the current research involves the neurobiological description of the behavioural inhibition system (BIS) associated with the septo-hippocampus region in the brain (Gray & McNaughton, 2003). According to this theory, information comes from the prefrontal cortex into the septo-hippocampal pathway which sends out the information to the noradrenergic fibres of the locus coeruleus. High activity in these areas of the brain due to increases in norepinephrine is hypothesised to be an indication of high levels of anxiety. Specifically, BIS responds to signals of potential punishment, unfamiliar novel stimuli, and fear-inducing stimuli by motivating the organism to stop doing things that may lead to punishment and by causing it to be highly alert. In brief, BIS compels the organism to avoid negative emotions. Research has associated BIS to the individual dimension of anxiety, specifically trait anxiety and vulnerability to anxiety (Carver & White, 1994).

In parallel, the system toward appetitive stimuli is termed the behavioural activation system (BAS) and is related to the personality trait impulsivity (Fowles, 1987). BAS is modulated within the septal area and the lateral hypothalamus and increased dopaminergic activity in these areas of the brain Section III- Anxiety 62


is an indication of high impulsivity and as such, causes an individual to be sensitive to potential rewards by motivating the organism to seek out positive experiences that trigger positive emotions (i.e., the ones that feel good) (Depue & Collins, 1999). Activation of the BAS is associated with feelings of hope and approach behaviours, whereas activation of the BIS is associated with feelings of anxiety and avoidance behaviours.

A third component known as the Fight-Fright-Freeze system (FFFS) was hypothesised to mediate reactions to all aversive/ punishing stimuli (conditioned and unconditioned), such as rage and panic, flight versus fight, and is sensitive to unconditioned aversive stimuli (Gray & McNaughton, 2003). FFFS is often referred to as the threat system and is presumed to be associated with fear, not anxiety although there still exists some debate about the relationship between fear and anxiety and how BIS competes with and modulates FFFS and vice-versa (Corr, 2002). Further detail on the BISBAS and FFFS will be provided in the second part of Chapter Five.

MEASUREMENT OF BIS AND BAS

The most widely used measure of BIS and BAS systems are the self-report questionnaires known as the BIS/BAS scales21 developed by Carver and White (1994). These scales assess, through a series of 20 items, sensitivity to BIS and BAS at a cognitive level. The items are rated on a 4-point Likert-type scale and comprise three BAS subscales and one BIS subscale. The BAS 21

See Appendix L Section III- Anxiety 63


Reward Responsiveness subscale has five items designed to assess positive response to reward stimuli, BAS Drive subscale has four items indicative of persistence in pursuit of reward, and BAS Fun Seeking subscale consists of four items indicative of willingness to approach novel and rewarding stimuli. The BIS subscale assesses concern over and reactivity to aversive events. Further information on the BIS/BAS scales will be provided in the second part of Chapter Five as they have been used to examine which of these two systems are likely to predict adolescent depression.

The objective of this section was thus to provide an overview of anxiety and highlight two psychological theories pertinent to the current research study.

The co-existence of depression and anxiety is an important

phenomenon commonly observed in clinical practice and this aspect will be henceforth explained in the following section.



SECTION FOUR: COEXISTENCE OF DEPRESSION & ANXIETY

Comorbidity implies the co-occurrence of two or more disorders, a phenomenon which is generally associated with a more serious course of illness (Kessler, McGonagle, Swarz, Blazer, & Nelson, 1993). Comorbidity is hypothesised to be due to either shared etiological factor(s) or one disorder being a risk factor for the development of subsequent disorders (Angold, Costello, & Erkanli, 1999).

1.4.1 COMORBIDITY OF ANXIETY AND DEPRESSION

The overlap of depression and anxiety was observed by scholars since the Ancient

World.

Hippocrates

recognised

their

co-occurrence

and

acknowledged that patients who experienced fear are also subject to melancholia (Akiskal, 2008). Albeit different terminologies used, eminent theorists including Galen, Jean-Martin Charcot, Pierre Janet, and Sigmund Freud never ceased recognising the overlap between anxious and depressive symptoms (Akiskal, 2008).

Comorbidity in adults for anxiety and depression can be as high as 70%, but typically ranges between 20% and 50% (Angold et al., 1999), although they often co-occur, sometimes one disorder follows the course of the other (Clark & Watson, 1991). Likewise, a significant and meaningful relation has 65


been found to exist between anxiety and depression in children and adolescents (Brady & Kendall, 1992; Cole, Truglio, & Peeke, 1997; Seligman & Ollendick, 1998) and studies have demonstrated the rate of anxiety disorders to be between 2 and 26 times higher in children with depression than children without depression (Angold & Costello, 1993). In fact, comorbidity between anxiety and depression is more common than the “pure” forms of any one of these disorders and therefore should be considered the rule rather than the exception in clinical practice and research (Crick & ZahnWaxler, 2003).

1.4.2 TEMPORAL RELATIONSHIP BETWEEN ANXIETY AND DEPRESSION

There is substantive evidence from adult and adolescent data that a temporal link exists between anxiety and depression, with anxiety disorders preceding onset of a Major Depressive Disorder (MDD)22 (Bittner et al., 2004; Costello et al., 2003, Flannnery-Schroeder, 2006; Seligman & Ollendick, 1998).

This sequence of anxiety preceding depression seems to be a

consequence of worry about future negative events and depression being triggered mainly by past negative events (Wittchen, Kessler, Pfister, & Lieb, 2000). In other words, over time the anxiety caused by the anticipation of an upcoming adverse life event will be transformed into depression after the event has occurred. In contrast, the pattern between anxiety and depression

22

See section 1.2.1 Section IV – Comorbidity 66


may differ for Persistent Depressive Disorder23 which has a tendency to precede the onset of anxiety disorders (Kovacs, Gatsonis, Paulauskas, Richards, 1989).

1.4.3 INFLUENCE OF ANXIETY ON SYMPTOM SEVERITY OF DEPRESSION

Children and adolescents with comorbid anxiety and depression have been found to report more severe depressive symptoms than those with either depression or anxiety alone (Stark, Humphrey, Laurent, Livingston, & Christopher, 1993), to have poorer global functioning than those without a history of comorbidity (Rohde, Clarke, Lewinsohn, Seeley, & Kaufman, 2001), and to have an increased risk for suicidal ideation and suicide attempts (Lewinsohn, Rohde, & Seeley, 1996).

Altogether these studies seem to

suggest comorbid anxiety and depression worsens the course of depressive symptomatology in children and adolescents (Axelson & Birmaher, 2001).

1.4.4 THEORETICAL EXPLANATIONS FOR COMORBIDITY

Several hypotheses have been put forward to explain the overlap of anxiety and depression and a few of these theories relevant to the current research will be briefly mentioned here and further elaborated in Chapter Five.

23

See section 1.2.2 Section IV – Comorbidity 67


Since the 1980s, the co-occurrence of anxiety and depression was explained by similar genetic diatheses (Kendler, 1996; Leonardo & Hen, 2006) with particular reference to serotonin transporter gene 5-HTTLPR (Stein, Schork, & Gelernter, 2007), involvement of same brain structures such as prefrontal cortex and amygdala (Heim, & Nemeroff, 2001), and shared neurobiochemicals such as serotonin and norepinephirine (McNaughton & Corr, 2004). Cognitive theorists have attributed the comorbid nature of anxiety and depression and their sequential pattern inasmuch as lack of perceived control over events.

Inability to control outcomes will foster negative anxiety

cognitions which in turn trigger helplessness and hopelessness, two characteristics of depression (Alloy, Abramson, Smith, Gibb, & Neeren, 2006). It has been further argued that cognitive processes involved in anxiety and depression have similar self-focused information processing, biased interpretations and negative expectations (Browning, Holmes, & Harmer, 2010). Among other dynamics, stress-diatheses in childhood pertaining to parental, family, and interpersonal functioning have been also found to be implicated in the development of anxiety and maintenance of subsequent depression (Taylor & Alden, 2006).

The co-occurrence of anxiety and depression has been also attributed to some degree to a common underlying trait, neuroticism (Mineka, Watson & Clark, 1998). Neuroticism is a personality trait characteristic of anxiety, moodiness, and worry, related to the activity of the limbic system (Rusting & Section IV – Comorbidity 68


Larsen, 1997). Neuroticism has been found to reflect level of BIS activity which modulates an individual’s vulnerability to develop anxiety and depression (Weinstock & Whisman, 2006). Further information on the link between neuroticism and BIS will be explicated in Chapter Five.

1.4.5 THE TRIPARTITE MODEL

So far, on one hand, the theories mentioned have highlighted the notion that anxiety and depression are facets of a unitary disorder because of shared etiological diatheses. On the other hand, Clark and Watson (1991) have posited that the affective domains of depression and anxiety entail both the identification of similar subtypes and specific elements of each dimension. Anxiety and depression are thus two discrete disorders with similar underlying aspects due to a common general factor, negative affect (NA).

NA refers to a general dimension of subjective distress and

unpleasurable engagement deemed to represent distress and a variety of affective states including upset, anger, guilt, fear, and worry, common to the two disorders (Watson, Clark, & Tellegen, 1988).

Section IV – Comorbidity 69

Negative Affect (NA)


Physiological Hyperarousal (PH)

Positive Affect (PA)

Figure 3: The tripartite model of depression and anxiety

According to the tripartite model (Figure 3), the best descriptor of depression is low positive affect (PA), whereas anxiety is characterised by physiological hyperarousal (PH).

PA encompasses mood states including

motivation, pleasurable engagement, and enthusiasm. Clark and Watson suggest that an absence of PA is reflected by despondent mood and fatigue whilst PH typically involves somatic tension, shortness of breath, dizziness, light-headedness, and dry mouth.

The tripartite theory of anxiety and

depression will be further expounded in Chapter Five of this dissertation, wherein empirical support for this theory will be mentioned together with its limitations.

The DSM nomenclature has until 1994 viewed anxiety and depression as two discrete disorders, however, a separate category mixed anxietydepressive disorder which neither belonged to the Mood Disorders nor to the Anxiety Disorders category was later included (APA, 2000). In the recent Section IV – Comorbidity 70


publication of the DSM, the mixed anxiety-depressive disorder was removed as a diagnostic category instead, clinicians are now expected to specify in the diagnosis of MDD and Persistent Depressive Disorder (formerly known as Dysthymic Disorder) whether anxiety is present (APA, 2013). The evolution of the DSM taxonomy thus demonstrates that depression and anxiety are now being recognised as categorically distinct constructs with a shared common feature, consistent with the tripartite model of Clark and Watson.

1.4.6 DIFFERENTIATING ANXIETY FROM DEPRESSION

The Depression Anxiety Stress Scale24 (DASS; Lovibond & Lovibond, 1995) is one such instrument originally developed to discriminate between symptoms of anxiety and depression. The DASS may not be as popular as the other measures of depression or anxiety such as the Beck Depression Inventory (BDI-II; Beck & Steer, 1996) and the Revised Children’s Manifest Anxiety Scale (R-CMAS; Reynolds & Richmond, 1997), but it has elicited a small but growing body of research literature over the past two decades.

The DASS scales were developed in Australia and based on clinical observations, their construct validity was refined using factor analytic methods during its early development. Originally, the core symptoms of depression were characterised by low positive affect whilst physiological hyperarousal was found to be unique to the experience of anxiety. Several

24

See Appendix A Section IV – Comorbidity 71


other items - for example fatigue and irritability - were found to have no strong or unique loading on either the depression or the anxiety factor and these items were considered non-specific but related to both anxiety and depression. More items of this nature were included and the stress scale emerged in addition to the existing depression and anxiety scales (Lovibond & Lovibond, 1995).

The DASS depression scale consists of fourteen items which assess dysphoria, hopelessness, devaluation of life, self-depreciation, lack of interest, anhedonia, and inertia. The anxiety scale also consists of fourteen items which measure levels of autonomic arousal, skeletal musculature effects, situational anxiety, and subjective anxious affect. The fourteen items of the DASS stress scale tap into levels of non-specific arousal which include difficulty relaxing, impatience and irritability. The structure of the DASS has both similarities and differences from the tripartite conceptual model proposed by Clark and Watson.

The DASS emphasises symptoms of

autonomic arousal in defining anxiety and highlights anhedonia or lack of positive affect, hopelessness and devaluation of life to define depression. However, the major difference is with respect to the items related to the third dimension stress, which is distinct from both anxiety and depression. According to the tripartite model, the non-specific symptoms are grouped into the negative affect, NA, category common to the two disorders however factor analytic procedures during the elaboration of the DASS have demonstrated that the items of the stress scale do not reflect symptoms that Section IV – Comorbidity 72


are common to anxiety and depression because they form altogether a separate factor.

Furthermore, although the three dimensions have a

moderate correlation, the items of the stress scale have been found to load negligibly on either the depression or the anxiety scale only. The authors of the DASS are of the opinion that the various syndromes this instrument measures are inter-correlated not because they share common symptoms, but rather because they share common factors, which may include genetic and environmental diatheses.

1.4.7 CLINIMETRICS OF THE DASS SCALES

There are two versions to the DASS, the longer 42–item version which consists of fourteen items on each of the three scales and the shorter version, the DASS-2125 which consists of seven items (taken from the DASS42) on each scale. In the following paragraphs, their psychometric qualities will be briefly presented.

The DASS-42

The normative sample of the DASS-42 comprised 1044 males and 1870 females with an age range between 17 and 69 years. Internal consistency measured by Cronbach’s alpha, for the depression, anxiety, and stress scales were .91, .84, and .90 respectively (Lovibond & Lovibond, 1995). The threefactor structure of the DASS-42 was consistently found in adult non-clinical 25

See Appendix B Section IV – Comorbidity 73


populations (e.g. Crawford & Henry, 2003). Similarly, in clinical populations the three-factor solution of the DASS-42 was found (Brown, Chorpita, Korotitsch & Barlow, 1997; Antony, Bieling, Cox, & Enns, 1998; Clara, Cox, & Enns, 2001; Page, Hooke, & Morrison, 2007). In a sample of patients with a primary diagnosis of mood disorder, α values for the three scales ranged between .89 and .96 (Page et al., 2007; Clara et al., 2001), whilst in anxiety disorder patients, internal consistency values ranged between .89 and .97 (Brown et al., 1997; Antony et al., 1998).

Concurrent validity of the DASS-42 is well established with other known measures of depression and anxiety such as the Beck Depression Inventory (BDI-II; Beck, Steer, Brown, 1996), the Beck Anxiety Inventory (BAI; Beck & Steer, 1990), the Hospital Anxiety and Depression Scale (HADS; Zigmond & Snaith, 1983), the Positive and Negative Affect Schedule (PANAS; Watson, Clark, & Tellegen, 1988), the Symptoms of Anxiety and Depression Scale (sAD; Bedford & Foulds, 1978), Symptom Checklist-90-R (SCL-90-R; Derogatis, 1994), and the Four Systems Anxiety Questionnaire (FSAQ; Köksal & Power, 1990).

The DASS-21

The abridged version of the original DASS, The Depression Anxiety Stress Scales (DASS-21; Lovibond & Lovibond, 1995) also consists of the three subscales designed to assess dysphoric mood, symptoms of fear and



autonomic arousal, and symptoms of tension and agitation. The DASS-21 contains half the number of items that make up the DASS-42; each dimension consisting of seven items. Apart from the advantage of being brief as it can be completed in 5 minutes, it is also easy to understand due to its simple language. Moreover, since both versions of the DASS are in the public domain, they are free and accessible over the internet using the following link:

http://www2.psy.unsw.edu.au/groups/dass/

The psychometric properties of the DASS-21 have been established in adult clinical (Henry & Crawford, 2005; Norton, 2007; Shea, Tennant, Pallant, 2009; Mahmoud, Hall, & Staten, 2010; Sinclair et al., 2011) and non-clinical populations (Antony et al., 1998; Clara, et al., 2001; Ng, Trauer, Dodd, Callaly, Campbell, & Berk, 2007; Gloster et al., 2008; Wood, Nicholas, Blyth, Asghari, & Gibson, 2010). Further information on the DASS-21 will be provided in Chapter Two as its psychometric qualities have been investigated in the current research study.

1.4.8 CHAPTER SUMMARY AND RATIONALE FOR RESEARCH

This chapter focused on stress, anxiety and depression within a psychological framework whereby theoretical components and empirical findings in adolescent populations were underscored. The importance of



having a validated psychometric tool adapted to the adolescent Mauritian population for screening these three psychopathologies has already been stated in the General Introduction of this dissertation. The first investigation of this study therefore attempts to empirically evaluate the factor structure and the external validity of the French version of the DASS-2126 in a nonclinical adolescent Mauritian sample.

Since no prior research using the

French DASS-21 has been conducted in Mauritius, exploratory factor analysis (EFA) will be used at the outset to determine the number of latent factors in the data set. Confirmatory factor analysis (CFA) will then be carried out, based on the findings of the EFA, to determine a factor model to be retained. Internal consistency and differential validity also will be examined. With regard to the external validity, the three scales of the French DASS-21 will be examined using other established measures of depression, anxiety, and stress, namely the MDIC, the RCMAS, and the CISS. In the final part of this research, the predictors of depression will be investigated using another set of established measures namely the BDI-II, the BIS-BAS scales, and the PSS.

26

See Appendix M for the French DASS-21 Section IV – Comorbidity 76

CHAPTER TWO: CONSTRUCT VALIDITY OF THE FRENCH DASS-21

Chapter 2: Construct validity of the French DASS-21

INTRODUCTION

Psychology is defined as the scientific study of mental processes and related behaviour (Reber & Reber, 2001). Since direct observation of mental processes and cognitions are not possible for researchers and clinicians, measurement of psychological constructs thus need to be inferred from other sources, for example through self-report measures which are designed to address that particular construct under investigation. Crucial to the field of psychology is psychometrics which concerns the development, evaluation, and generalisation of measures for specific psychological constructs.

For

instance, a questionnaire developed to measure severity of anxiety symptoms, based on a theoretical foundation, would need to be evaluated empirically to determine how well it would assess that anxiety construct. Thus, psychometrics is intrinsically linked to the concepts of reliability and validity which determine the accuracy of a psychological measurement.

Reliability refers to the capacity of an instrument to be consistent in its measurement, whereas validity refers to the appropriateness of the testing instrument, i.e. whether the instrument is measuring what it is intending to assess (Anastasi & Urbina, 1997). Both reliability and validity are not entities but concepts which exist through the inferences made from the testing instrument. In psychometrics, reliability and validity are of different types

78


and each is determined through different ways of data collection, set of conditions and mathematical procedures. An instrument cannot be valid unless it is reliable however, the reliability of an instrument does not depend on its validity (Nunnaly & Bernstein, 1994). Calculating Cronbach’s alpha value of an instrument has become common practice in clinical research for estimating reliability when multiple items measure a construct.

RELIABILITY: CRONBACH’S ALPHA

The internal consistency of a test or a scale is measured by Cronbach’s alpha which is expressed as a value ranging between 0 and 1 but in psychometric research, acceptable values of alpha are expected to range between 0.7 and 0.9 (Cronbach, 1951; Tavakol & Dennick, 2011). Internal consistency describes the extent to which all the items in a test measure the same dimension or construct and hence it is connected to the interrelatedness of the items within the construct. If the items in a test are correlated to each other, the value of alpha is high.

However, a high

coefficient alpha (α > .90) is not always equivalent to a high degree of internal consistency but may sometimes suggest that some items on a scale are redundant as they are testing the same dimension but in a different way. Alpha can be also affected by the length of the test, for example, if the test length is too short, the value of alpha may be small. Thus, to increase alpha, more related items testing the same concept should be added to the test. It is also important to note that alpha is a property of the scores on a test from a specific sample of respondents. Therefore researchers should not rely on

Introduction 79


published alpha estimates but should measure alpha each time the test is administered.

CONSTRUCT VALIDITY

Since the aim of the current study is to also examine the construct validity of the French DASS-21 scales, the following sections of this chapter will therefore focus on the salient aspects of this form of validity.

The construct validity of a scale refers to its ability to account for the dimension it is intended to measure. According to Cronbach and Meehl (1955), measuring the construct validity involves developing a theory about the observable variables of a psychological dimension or construct, then empirically determining the hypothetical association between the intended psychological dimension and its observed variables.

Factor analytic

procedures are commonly used to examine the relationship between the observed variables (i.e. items in the questionnaire) and their corresponding factors (i.e. constructs). This approach is also known as factorial validation and it explicitly demonstrates the theoretical interdependence of observed variables (items) and latent variables (constructs).

The two common methods of determining the construct validity of a questionnaire are through exploratory and confirmatory factor analytic procedures. Exploratory factor analysis (EFA) is generally used in the early stages to determine the factor structure of an instrument whilst confirmatory

Introduction 80


factor analysis (CFA) requires that the link between observed and latent variables be known in advance, based on a theoretical concept. Thus CFA makes it possible to test whether a proposed factor structure based on theoretical models fits the data set, but also it evaluates the degree of fit between the observed and latent variables (Byrne, 2006).

KEY ASPECTS IN CROSS-CULTURAL VALIDATION

The issue of determining validity and reliability of measures in psychology began during World War I with the development of group intelligence measures (Sticht & Armstrong, 1994). Researchers at the time found that subjects could be intelligent but illiterate and/or intelligent but not proficient in English, which was the language used by the researchers. As a result, the Army Alpha (for English-literate examinees) and the Army Beta (for examinees not literate or fluent in English) were developed and have evolved many years later into the Verbal and Performance indices of the Wechsler Intelligence Scales.

The strict use of nonverbal measures to assess psychological constructs provides only an approximate picture of the individual’s functioning because verbal abilities are also important aspects of psychological functioning (Sattler, 2001). Since the majority of psychological tests are developed in the Anglo-Saxon world and validated in English-speaking populations, some theorists circumvent the issue of assessing populations with different cultural and linguistic backgrounds by relying on informal evaluations, such as record

Introduction 81


review, behavioural observation, parent and teacher interview, and dynamic assessment (Laing & Kamhi, 2003). Others have made use of interpreters to provide on-the-spot translations of psychological measures or simply have made changes or adaptations of standardised procedures during testing. These practices have given rise to other difficulties, paramount among them is that of psychometric qualities which are being violated when instruments are translated or when standardised procedures are not respected during testing (Hambleton, 2001). According to the Standards for Educational and Psychological Testing (AERA, APA, & NCME, 1999), there are three major conditions that apply when the language of origin of psychological tests is modified: 1) When a test user makes a substantial change in the language of a test, the user should revalidate the use of the test for the changed condition; 2) When a test is translated from a source language to a target language, its reliability and validity for the groups being tested should be established; and 3) When two different language versions of the same test are intended to be comparable, evidence of test comparability should be reported.

In this perspective, cross-cultural psychology recognises that it is not enough to simply translate a measure from one language to another because translation does not take into account changes in references to culture, content, and wording when a different language version of an existing

Introduction 82


measure is construed (Malda, van de Vijver, Srinivasan, Transler, Sukumar, & Rao, 2008). As an example, a French-speaking person from Canada can understand other French-speaking persons from France or Mauritius despite different dialects and accents.

However, when it comes to measuring

constructs in a psychometric instrument, the vocabulary utilised needs to be familiar and carefully chosen in order to be understood by the target population.

The most popular design for translating a test from a source language to a target language is the backward translation or back translation design (Hambleton, 2001). In this case, the original test is translated and a different bilingual translator, who has not had prior exposure to the test in its source version, translates it back into the original language. The two versions are then compared and judged as to their equivalence. The translation and backtranslation steps can be repeated in order to reduce any discrepancies that may arise (Bracken & Barona, 1991). The final version of the target test can then be evaluated by a different bilingual person or by a committee of bilinguals.

This design ensures that the source and target versions are

comparable in meaning because the translator who conducts the backtranslation has had no prior knowledge of the original test items, indicating to the developers that the target population would likely have the same understanding of the items in their cultural context as would two independent translators (La Heij, Hooglander, Keling, & van der Velden, 1996).

Introduction 83


Sometimes forward-translation design is used whereby a translator who is fluent in both the source and target languages translates the test and a different bilingual person or group of bilinguals compares the source version with the target version. The drawback of this research design is the degree of inference that is made by the translator(s) with respect to the equivalence of the target version with the source version. The translators may not have sufficient knowledge of the use of particular words underlying a construct in the source test- item, and therefore the use of a particular word in the target test items could be significantly different from the source test items. Taking the example of the term “population” which has one meaning to the lay person, may also have another specific meaning within the discipline of statistics for example. With the forward-translation design, the significance of such a term or the understanding of the term at the semantic level by the target population could be lost when test developers are not cognisant of its intended semantic use (La Heij et al., 1996).

Overall, in order to limit difficulties related to cultural and language test bias as well as psychometric validation issues, it is useful to have appropriately standardised and normed instruments for the target population (Unruh & Lowe, 2010). In fact, the term adaptation is often used in lieu of translation as it encompasses a broader approach for the utilisation of a test originally developed in one language and culture for its use in a different ethnic group.

Introduction 84


THE DASS-21

There are many popular tests which have been adapted successfully to other languages and cultures because due attention has been given to the translation issues already discussed above. One such instrument is the DASS which has been translated in more than 30 languages and is now widely used in clinical and non-clinical settings across the world.

Internal consistency of the DASS-21 has been found to be excellent in English-speaking non-clinical adult samples, with α values ranging from .90 to .95 in the UK (Crawford & Henry, 2003), and from .85 to .88 in Malaysia (Imam, 2008). Translated versions also had good internal consistencies, with α values ranging between .89 to .96 for the Italian translation (Severino & Haynes, 2010), between .90 to .92 for the Turkish version (Akin & Çetin, 2007), .84 to .93 for the Spanish translation (Daza, Novy, Stanley, & Averill, 2002; Bados, Solanas, Andrès, 2005), between .86 and .92 for the Portuguese translation (Apòstolo, Mendes, Azeredo, 2006; Vignola & Tucci, 2013), between .91 and .94 for the Greek version (Lyrakos, Arvaniti, Smyrnioti, & Kostopanagiotou, 2011), between .57 and .93 for the Chinese translation (Chan et al., 2012), between .84 and .87 for the Arabic version (Taouk, Lovibond, & Laube, 2001) and between .85 and .87 for the Persian (Farsi) translation (Asghari, Saed, & Dibajnia, 2008).

Introduction 85


THE CONSTRUCT VALIDITY OF THE DASS-21 IN ADOLESCENT SAMPLES

A total of six studies to date have examined the construct validity of the DASS-21 using non-clinical adolescent samples, of which four were conducted in Australia, one in Malaysia, and another one in Belgium. The findings on the factor structure of the DASS-21 have not been conclusive and each will be briefly mentioned below.

Duffy, Cunningham, and Moore (2005) did not find the original threefactor structure of the DASS-21 in their Australian adolescent sample, instead they proposed a two-factor model consisting of a physiological arousal factor and another factor which clustered together lack of positive affect items and generalised negativity items. Tully, Zajac, and Venning (2009) found that their Australian sample data best fitted a two-factor model where depression and anxiety items were allowed to load on their respective factors but also on a negative affect factor on which the stress scale items were also allowed to load.

Similarly,

Willemsen, Markey, Declercq, and Vanheule (2011) found that the model proposed by Tully and colleagues provided a better fit for their Belgian adolescent sample. Szabo (2010) found that a quadripartite model, which allowed all items to load on a general factor and at the same time on their respective dimensions, provided a slightly better fit for her Australian adolescent sample. Patrick, Dyck, and Bramston (2010) found a one-factor solution to be appropriate compared to the original three-factor model in their Australian Introduction 86


adolescent sample. Likewise, Hashim, Golok, and Ali (2011) opted for a onefactor model with reasonable model fit in their Malaysian adolescent sample.

RATIONALE FOR THE CURRENT STUDY

As previously stated in the General Introduction of this dissertation, depression is the major cause of suicidal behaviour and the suicide rate among the Mauritian youth is of concern. The lack of an adapted measure to evaluate emotional distress among Mauritian adolescents underscores the need for an instrument that assesses depression severity, anxiety levels (which precedes onset of depression), and stress levels which act as risk factors for the development of both anxiety and depression. Since the lingua franca of Mauritians is French, therefore this research is pioneering in that it attempts to examine the internal validity of the French version of the DASS-2127. Specifically, the internal consistency and construct validity of these scales in an adolescent Mauritian community sample will be examined.

27

See Appendix M

Introduction 87


METHOD

PARTICIPANTS

Participants were recruited from two private and two state secondary schools in order to reduce the possibility of biases related to the type of institution. The two private schools were the Doha Academy girls section and boys section located in Phoenix and the state secondary schools Dr. R. Chaperon (boys section) located in Belle Rose, and the Swami Sivananda (girls section) located in Bambous (Figure 4).

All four schools accommodate

students from urban and rural areas in the vicinity of the school. The distribution of boys’ and girls’ participation across the four schools is shown in Figure 5.

Figure 4: Map of Mauritius showing location of schools

88


Figure 5: Distribution of boys and girls across the four schools

A total of 1186 adolescents participated in the present research study with 801 girls representing 67.5% of the sample. Age range for the total sample was between 11 and 19 years, with mean age, M= 14.3 years, and standard deviation, σ = 2.1. PROCEDURE

Ethical approval was sought and obtained from the institutions’ principals and from the relevant department of the Ministry of Education of Mauritius. Participation was voluntary and all questionnaires were administered on school premises during non-teaching class period.

Participants were

explained verbally how to respond to the set of questionnaires and they were assured of the confidentiality of their responses.

In this respect, each

participant was randomly assigned an index number which was to be

Method 89


produced on their set of questionnaires so that their participation would remain anonymous. The researcher was assisted by a psychology graduate to help the students with any queries pertaining to the items on the questionnaires. Data for this study was collected over a period of four months from May 2010 to September 2010. MEASURES

The French version of the DASS-21 was used in this study as French is the lingua franca of Mauritian adolescents, i.e. it is spoken, understood and studied at school by all students in Mauritius. The French DASS-21 was translated from the original DASS by Professor Donald Martin of the University of Ottawa, Canada. This version can be obtained over the internet on the DASS website: http://www2.psy.unsw.edu.au/DASS/translations.htm Response and coding of the French DASS-21 is similar to the original English DASS-21 scales as the participants rate their responses on a fourpoint Likert scale ranging from 0 (does not apply to me at all) to 3 (applies to me most of the time). Item scores on the DASS-21 are doubled to be comparable to the original DASS-42 questionnaire for clinical interpretation. STATISTICAL ANALYSIS

Descriptive statistics, reliability statistics, and exploratory factor analysis were computed using XLStat (XLStat 2012.2.01; Addinsoft) and SPSS

Method 90


(SPSS 16.0 for Windows; SPSS, Inc).

Confirmatory factor analyses were

performed with AMOS (AMOS 20; IBM SPSS).

RELIABILITY: INTERNAL CONSISTENCY

Internal consistency estimates were computed for each DASS-21 scale and item-scale correlations were also examined to identify any items affecting the scales’ reliability.

FACTOR ANALYTIC PROCEDURE

Unlike SPSS, AMOS does not function with missing values and therefore the total sample (N=1186) was reduced to 1002 because 184 questionnaires were considered invalid as the participants did not respond to all items on the DASS-21. This sample was divided into two groups using the odd-even split method so that half of the sample (n = 501) was used for EFA using SPSS and the remaining half for CFA on AMOS. EXPLORATORY FACTOR ANALYSIS As there is no prior empirical evidence that could guide the assumptions about the factor structure of the DASS-21 scales in a Mauritian adolescent population, construct validity began with EFA to identify the number of factors to be extracted. Half of the data set (N=501) was therefore factoranalysed using principal axis factoring.

In factor analytic procedures, sample size is an important aspect to consider for meaningful interpretation (Gorsuch, 1983). However, there is no

Method 91


clear consensus as to the exact number of respondents required, for example Tabachnick and Fidell (2007) recommend at least 300 participants, whilst Meyers, Gamst, and Guarino (2006) recommend roughly 250 participants for a questionnaire of 25 items and 400 participants for a 90-item scale. For Nunnally and Bernstein (1994), 10 respondents per item can be considered as a benchmark to determine sample size for factor analysis. Given these recommendations, a minimum of 210 participants would have been sufficient for the current analysis but the sample size exceeded the minimum recommended (N=501) and was thus considered adequate for factor analyses. In addition, it is recommended for correlation between items and their corresponding factors to have a loading value above .30 (Tabachnick & Fidell, 2007), whereas appropriateness of principal components analysis (PCA) is determined by Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy which is expected to have a value above .6 to be considered adequate for factor analysis (Meyers et al., 2006).

After extraction, factors were rotated through an oblique procedure (promax), which assumes that the underlying factors are correlated based on theoretical models. This procedure allows for inter-correlations between factors to influence the analysis to produce clinically meaningful solutions (Tabachnick & Fidell, 2007).

The following three techniques were used to identify the number of factors to be extracted:

Method 92


a) Eigenvalues greater than the value of 1. Eigenvalues represent the total amount of variance accounted for in all of the variables (items) on each factor. The eigenvalue criteria of greater than or equal to one (>1) was selected because factors with eigenvalues of less than one are no better in accounting for the variance in the variables than a single variable which has a variance of 1 (Nunnally & Bernstein, 1994). b) Natural breaks in the scree plots. Scree plots were also examined to determine the number of factors to extract.

Scree plots give a visual representation of the total variance

associated with each factor. They show the rate at which eigenvalues decrease as the number of factors increase. Natural breaks observed in scree plots aid in determining the number of factors to extract (Nunnally & Bernstein, 1994). c) Psychological meaningfulness of the solutions. Factors were extracted based upon the interpretation of the solutions obtained and the theoretical concepts on which the DASS-21 was constructed.

Method 93


CONFIRMATORY FACTOR ANALYSIS

Confirmatory factor analysis (CFA) was conducted on the remaining half of the dataset using AMOS statistical package. CFA requires that number of factors and variables making up each factor be specified. Based on the number of factors identified in EFA, models were then tested and compared against models identified in other research studies on the factor structure of the DASS-21.

Kline (2005) recommends reporting the chi-square statistic, χ2, and because χ2 statistical test is sensitive to the sample size. Five commonly used fit indices were used to assess the adequacy of the model tested:

1. the ratio χ2 value / degrees of freedom (χ2/df) such that the range between 1 and 3 indicates acceptable fit, and values near 2.0 or below are considered good fit; 2. Comparative Index Fit (CFI) with values greater than .90 and close to .95 indicate goodness of fit, but values above .95 are considered better; 3. Root Mean Square approximation (RMSEA) between .00 and .05 is considered good fit; 4. Goodness-of-fit (GFI) index to range between .90 and less than 1.0 for acceptable fit and;

Method 94


5. Standardised Root Mean Square Residual (SRMR) values less than .05 and closer to zero indicate relatively better fit when models are compared. Statistical results of both factor analytic procedures, EFA and CFA, with Cronbach’s alpha values are provided in the following results section.

Method 95


RESULTS

NORMALITY TESTING Preliminary analysis of the data was conducted to ensure that there was no violation of assumptions of normality.

The data was assessed for

normality based on an examination of skewness and kurtosis statistics which should fall within the range -2 to +2.

The mean, standard deviation, kurtosis and skewness statistics for each scale are presented below (Table 1).

The results suggest that the data

followed a normal distribution. Table 1: Descriptive statistics for the three DASS-21 scales

Depression

Anxiety

Stress

13.16

11.11

14.15

9.48

8.31

9.23

Skewness

.76

.79

.56

Kurtosis

.03

.22

-.45

Mean Std. Deviation

INTERNAL CONSISTENCY Internal consistency of the DASS-21 was estimated using Cronbach’s alpha, α, for each scale. The values obtained were satisfactory and were

Results 96


comparable to those of previous research conducted in adolescent populations (Table 2). Table 2: α values for the DASS-21 across studies in adolescent populations

Present study

Tully et al. (2009)a

Szabo, M. (2009)b

Hashim, et al. (2011)c

Willemsen et al. (2011)d,e

Depression

.79

.88

.87

.68

Male .76

Female .78

Anxiety

.72

.79

.79

.67

.72

.74

Stress

.78

.93

.83

.70

.81

.76

aTully et al. (2009) used a sample of 4039 secondary school students aged 12 to 18 years. bSzabo, M. (2009) used a sample of 484 Australian secondary school students aged between 11 and 15 years. c Hashim, et al. (2011) used a sample of 750 Malaysian secondary school students aged between 13 and 14 years. dWillemsen et al. (2011) used a sample of 378 Belgian secondary school girls with an mean age M = 13.76, σ = 1.66 eWillemsen et al. (2011) used a sample of 299 Belgian secondary school boys with an mean age M = 13.80, σ = 1.59

Upon examination of item-total statistics, all items on each scale were considered worthy of retention as alpha values would have changed by only .007 should they have been removed from their corresponding scales.

CONSTRUCT VALIDITY: FACTOR ANALYTIC RESULTS The following subsections will expand on exploratory and confirmatory factor analyses.

EXPLORATORY FACTOR ANALYSIS

PCA was conducted to evaluate the structure of the DASS-21 and KaiserMeyer-Olkin (KMO) measure of sampling adequacy was good .93 (above the recommended value of .6) and Bartlett’s test of sphericity was significant (2(210) = 2850.3, p < .001).

Results 97


The number of factors to be extracted was determined by eigenvalues greater than 1, and the scree test. Three factors emerged with an eigenvalue greater than 1, whilst the scree plot supported the extraction of only one factor (Figure 6) with an eigenvalue of 6.8 accounting for 32.56% of variance. The remaining two factors yielded eigenvalues of 1.16 (5.5% of variance), and 1.07 (5.1% of variance).

100

7 80

Eigenvalue

6 5

60

4 40

3 2

20

1 0

Cumulative variability (%)

8

0 F1 F3 F5 F7 F9 F11 F13 F15 F17 F19 F21

factors

Figure 6: Scree Plot

Since the scree plot and eigenvalues do not agree on the number of factors to be extracted, it was thus decided to proceed with an oblique rotation (promax) and force the number of factors to be extracted set to values 1, 2, and 3. The results for the one-factor and two-factor solutions are to be found in the appendix section28. For the one-factor solution, all items had a loading value above .40. Similarly when two factors were forced, all items loaded above .40: items of the depression and stress scales loaded on the first 28

See Appendix N & Appendix O

Results 98


factor together with three items from the anxiety scale related to worry and apprehension. The second factor consisted only of items on the anxiety scale specific to autonomic (somatic) arousal. When three factors were specified, all three components emerged with eigenvalues greater than 1, which is consistent with the theoretical framework of the DASS-21. The components that emerged were identifiable as stress, depression, and anxiety respectively (Table 3).

Correlation between these three components was moderate:

depression-anxiety r = .43; depression-stress r = .62; and anxiety-stress r = .48. Most items loaded on their corresponding dimensions above .30 and few showed mixed loadings.

The depression items 13 and 21 loaded more

strongly on the stress scale than on their intended scale. Similarly, anxiety scale items 9, 15 and 20 showed split loadings between stress and anxiety components. Although these items loaded on the component that defines them, the possible reasons for the mixed loadings will be reviewed in the following discussion section of this chapter.

Results 99


Table 3: Factor loadings above .30 using promax rotation.

Factor loadings Scale

Item

1

2

3

3.couldn't experience positive

-

0.68

-

0.50

-

Depression

5.difficult work up initiative 10.nothing look forward

-

0.74

-

13.sad and depressed

0.67

0.50

-

16.unable become enthusiastic

-

0.72

-

17.not worth much as person

-

0.65

-

21.life meaningless

0.64

0.58

-

2.dryness of mouth

-

-

0.58

4.breathing difficulty

-

-

0.76

7.trembling

-

-

0.67

9.worried situations panic

0.71

-

0.30

15.close to panic

0.58

-

0.46

19.aware action heart

-

-

0.64

20.scared for no good reason

0.63

-

0.30

1.hard to wind down

0.59

-

-

6.over-react to situations

0.50

-

-

8.using nervous energy

0.63

-

-

11.getting agitated

0.56

-

-

12.difficult to relax

0.68

-

-

14.intolerant kept doing

0.52

-

-

18.rather touchy

0.61

-

-

Anxiety

Stress

Results 100


CONFIRMATORY FACTOR ANALYSIS

CFA was performed with Maximum Likelihood estimation method which is a statistical means used to estimate all model parameters simultaneously (Kline, 2005). Moreover, this technique is used for reasonably large sample sizes (N>200). A summary of CFA results of all models tested are presented in Table 5.

A one-factor model (Figure 7) was tested because there was a ‘break’ on the scree plot in the EFA after the first factor (eigenvalue = 6.8).

In this

model, all items were forced to load on one factor and even if the indices were within acceptable values of good fit, GFI failed to converge (see Table 5). The one-factor model was therefore rejected.

Results 101


Figure 7: One-factor model showing standardised estimates

A quadripartite structure based on the model proposed by Henry and Crawford (2005) (Figure 8) was also tested. Adequate fit was obtained on all indices [χ2 (168, N=506) = 279.8, p < .001, RMSEA =.036 CFI=.96, SRMR = .035].

Results 102


Figure 8: Quadripartite model showing standardised estimates

Previous studies on adolescent samples retained two different models: the two-factor structure proposed by Duffy and colleagues (2005) (Figure 9) and the hierarchical bi-factor model (Figure 10) by Tully and colleagues (2009). The factor structure proposed by Duffy and colleagues comprised the four physiological arousal items (2, 4, 7 & 19) and the rest of the items were allowed to load on a generalised negativity factor. The indices obtained fitted the data well with χ2(188) = 406.6; p < .01; CFI = .92; RMSEA = .048; GFI = .93; SRMR = .043.

Results 103


Figure 9: Two-factor model showing standardised estimates

The hierarchical bi-factor model was tested based on the proposed model by Tully and colleagues (2009) and Osman and colleagues (2012) where all items were allowed to load on a general negative affect factor and items specific to depression and anxiety factors were allowed to load on their

Results 104


respective factors (Figure 10). The indices provided adequate fit χ2(174) = 349.1; p < .01; Δ = 2.00; CFI = .94; RMSEA = .045; GFI = .93; SRMR = .039.

Figure 10: Hierarchical bi-factor model showing standardised estimates

When three components were forced in the oblique rotation, three factors corresponding to the three DASS-21 scales emerged. The correlated three-factor structure (Figure 11) proposed by Lovibond and Lovibond (1995) was thus tested in the CFA. The indices obtained fitted the data relatively well χ2(186) = 389.2; p < .01; Δ = 2.09; CFI = .93; RMSEA = .047; GFI = .93; SRMR = .042. In this model, the anxiety scale items that had the weakest loadings, λ, were those (items 2, 4, 7, and 19) associated with core somato-visceral (physiological) symptoms of anxiety, whereas items depicting verbal-

Results 105


subjective anxiety (negative apprehension) had the strongest loadings. This could be due to the fact that these symptoms are specific to pathological anxiety and as such, may not be as relevant in a non-clinical sample, hence their weak loadings.

Results 106


Figure 11: Three-factor model showing standardised estimates

Correlation value φ which assesses the strength of link between latent factors was high: depression-anxiety = .86; anxiety-stress = .91; depressionstress .92. These values φ were comparable to those obtained in previous international studies which supported the three-factor structure of the DASS-

Results 107


21 in adult non-clinical samples (Table 4). The implications of these findings will be discussed in the following discussion section.

Table 4: Phi-values (φ) between the three factors on the DASS-21

Current study Mauritius Depression-Anxiety

.86

Sinclair et al. (2011) US .88

Asghari et al. (2008) Iran .82

Bados et al. (2005) Spain .63

Depression-Stress

.92

.85

.85

.55

Anxiety-Stress

.91

.86

.80

.71

Table 5: Summary of CFA results for different models tested

Model tested

χ2

df

Ratio

CFI

RMSEA

GFI

SRMR

χ2/df One-factor

431.6

189

2.28

.92

.050

----

.0442

Two-factor

406.6

188

2.16

.92

.048

.93

.0430

Hierarchical bi-factor

349.1

174

2.00

.94

.045

.93

.0390

Three-factor

389.2

186

2.09

.93

.047

.93

.0421

Quadripartite

279

168

1.66

.96

.036

.95

.0350

χ2 = Chi-square; df = degrees of freedom; χ2/df = relative Chi-square; CFI = Comparative Fit Index; RMSEA = Root Mean Square Error of Approximation; GFI = Goodness of fit index SRMR = Standardized Root Mean Square Residual.

INTERNAL VALIDITY Patterns of correlations between the three dimensions of the French DASS-21 were examined using Pearson’s correlation.

These correlation

values were positive, strong and significant (see Table 6). Previous studies using adolescent samples have not reported the correlation values between

Results 108


the three DASS-21 dimensions because the original three-factor structure has not been replicated. In the current study, these correlation values were comparable to those obtained in studies on the original and translated versions of the DASS-21 in adult samples (Akin & Cetin, 2007; Apostolo et al., 2006; Asghari et al., 2008; Chan et al., 2012; Daza et al., 2002; Imam, 2008; Lovibond & Lovibond, 1995; Sinclair et al., 2011), thereby establishing the internal validity of the scales. Table 6: Pearson correlation values between the three DASS-21 scales

DASS-21 scale

1

2

1. Depression

-

2. Anxiety

.64*

-

3. Stress

.71*

.67*

3

-

*p .05 on the stress scale. There was a statistically significant main effect for age, F (2, 996) = 3.13, p .05 and age group, F (2, 996) = .12, p> .05 did not reach statistical significance, on the DASS-21 anxiety scale. Given a significant interaction effect, F (2, 996) = 12.02, p .05 and age group, F (2, 996) = 1.61, p> .05 did not reach statistical significance on the DASS-21 depression scale. Given a significant interaction effect, F (2,996) = 5.81, p .05.

INDEPENDENT SAMPLES T-TESTS

In order to assess gender differences in each age-group, independent samples t-tests were carried out (see Table 11). In the 11-13 year-old group, the mean scores of boys on the three scales were statistically higher than those of girls at the .05 level of significance. In the 14-16 year old group, only on the depression scale that boys (Mboys = 14.68, σboys = 10.08) scored significantly higher than girls (Mgirls = 12.61, σgirls = 8.81) at the .05 level of significance (t

(407)

= -2.1, p = .037), whereas on the two other scales, the

differences were non-significant. Such results in the two age-groups do not support previous research findings on reports of depression, anxiety, and stress between the two genders. It is possible that the sample of boys from one school in particular has influenced the results as these students reportedly have externalising behaviours related to aggression and substance use. Such behaviours in psychological research among adolescents have been linked to high levels of stress which in turn are precursors to the development of depression and anxiety (e.g. Compas et al., 1993). However, in the 17-19 year old group, across the three scales girls scored significantly higher than boys and those results go in line with the general observation

Results 131

Chapter 3: Differential validity of the French DASS-21 scales

that females have a tendency to score higher than males on depression, anxiety, and stress.

Results 132

Chapter 3: Differential validity of the French DASS-21

DISCUSSION

Research on the structural relations between symptoms of anxiety and depression on psychometric instruments has given little importance to invariance across gender.

Such examination is necessary to test the

assumption that the relationship among symptoms of anxiety and depression are the same for females and males given the foregoing gender difference in the prevalence of anxiety and depression as from adolescence at both symptomatic and syndromal levels (Kessler et al., 1993). Testing invariance of an instrument across gender ensures that differences between males’ and females’ responses are not merely due to the measurement being genderbias.

Results from CFA indices demonstrated that the three-factor structure of the French DASS-21 is supported across the two genders, indicating gender invariance, similar to the findings of Gomez (2013) using non-clinical adults. Therefore the French DASS-21 can be interpreted in the same way for the two genders in adolescent community settings. Correlations between latent factors were relatively high compared to those obtained by Willemsen and colleagues (2011) in their Belgian sample indicating that the three factors are not empirically distinguishable presumably due to the common general affective distress.

133


Having established that the French DASS-21 factor structure is fundamentally the same for both girls and boys, it was possible to conduct gender comparisons with sufficient support that any gender difference found at the mean level would not be due to measurement error associated with gender bias within the construct of the measurement. In the two younger age groups, boys scored higher than girls across the three scales of the DASS21 and this may be attributed to the large portion of the sample of boys evolving within an environment where aggressive behaviours and substance abuse are present. However, girls in the 17-19 year-old age group scored significantly higher across the three DASS-21 scales thus corroborating the general observations made on these dimensions between the two genders.

Some differences on mean scores across age groups were observed. On the three scales, the mean scores for girls across the three age groups reached statistical significance, but the effect was small; nevertheless the increasing mean scores across age groups may be attributed to the psychological and social factors associated with the developmental transition from childhood to adulthood. On the depression scale only that there was a significant difference across age groups on mean scores for boys, with the youngest age group scoring statistically higher than the eldest age group. Again, the psychological and social changes associated with early adolescence in boys may be proximal cause to account for such a difference, but nevertheless this would require further investigation in future studies.

Discussion 134


Apart from the shortcomings already identified in the previous chapter, this study on gender differences did not have an equally balanced number of males and females in each age group category. Moreover it would have been commendable to have CFA conducted for each age-group category to test whether the data fitted the French DASS-21 three-factor model as age is an important factor when considering developmental clinical psychology.

Discussion 135

CHAPTER FOUR: EXTERNAL VALIDITY OF THE DASS-21

Chapter 4: External validity of the French DASS-21

INTRODUCTION

It was laid out in the precedent chapters that crucial to the development and the use of a psychological instrument is the concept of validity. Although in the 1940s, the validity of any dimension was reduced to establishing a correlation with a dependent variable in the intended manner (Guilford 1946), it was almost a decade later that validity standards were first codified. At the time, validity was divided into four categories depending upon the objectives of the test: content validity related to the core theme of the dimension, i.e. whether the set of items measure the given dimension. For unobservable traits such as anxiety, construct validity was important to reflect theoretical concepts regarding the phenomenon while concurrent validity was to be established with other measures of the same construct and finally, predictive validity was to be established when a dimension can predict the outcome on other measures of the same construct in the future (APA, 1954).

THE EVOLUTION OF THE CONCEPT OF VALIDITY

A later version of the codified guidelines for psychological tests subsumed concurrent and predictive validities under the label criterionrelated validity (APA, AERA, & NCME, 1966).

Over the decades, the

conceptualisation, definition, and inclusion of some 122 different types of 137


validity were used in research (Newton & Shaw, 2013) and integrated within the predominant four-validity-model structure albeit growing pressure to have construct validity as the dominant model which would subsume the remaining types of validity (Guion, 1977; Messick, 1989). Thus, the notion of validity as a unified framework consisting of multi-faceted and adjunct forms of validity became the central basis for contemporary validity theory (Shepard, 1993). Six aspects in the unified theory of validation have been proposed (Messick, 1995):

1) The content aspect of construct validity involves evidence of the relevance of items in the assessment of the dimension under investigation, principally through factorial validity (Messick,1989); 2) The substantive aspect typifies theoretical rationales and empirical data (Embretson, 1998); 3) The structural characteristic examines reliability of the responses to the structure of the construct (Messick, 1989); 4) The generalisability aspect assays whether the test can be used across population groups, and settings (Hunter, Schmidt, & Jackson,1982); 5) The consequential part appraises the potential risks associated with score interpretation in regard to issues of bias, and fairness (Messick, 1989);

Introduction 138


6) The external aspect includes concurrent, divergent, and predictive evidence from multifaceted comparisons (Garson, 2013).

The DASS-21 has actually passed all of the above validity criteria in adult populations across international settings. Similarly, in the current research study, factorial validity has been established, alongside internal reliability, internal validity, and generalisability across gender. The only tenet that needs to be examined is its external validation, i.e. concurrent and divergent validities. Concurrent validity, on one hand, refers to the degree to which the dimension(s) of an instrument correlate(s) with other measures of the same construct, at the same time. It is expected that when a measure is compared with another measure of the same type, they will be related (or correlated). On the other hand, divergent validity (also referred to as discriminant validity) is established when two distinct constructs are unrelated when compared to one another (Campbell & Fiske, 1959; Messick, 1989). Weak correlation coefficient between measures of a construct and measures of conceptually different constructs are usually given as evidence of divergent validity.

STUDIES ON THE EXTERNAL VALIDATION OF THE DASS

Previous investigations in English-speaking and non-English-speaking countries have established concurrent and divergent validities of the DASS-42

Introduction 139


and DASS-21, as well as their translated versions with measures including the Beck Anxiety and Depression Inventories (Asghari et al., 2008; Brown et al., 1998; Daza et al., 2002; Lovibond & Lovibond, 2005; Norton, 2007; Osman et al., 2012), the Positive and Negative Affect Scale (Crawford & Henry, 2003; Norton, 2007), the Symptom Checklist-90-R (Bados et al., 2005), the Hospital Anxiety and Depression Scale (Musa, Ramli, Abdullah, & Sarkasi, 2011; Ownsworth, Little, Turner, Hawkes, & Shum, 2008), the Mood and Anxiety Symptom Questionnaire-90 (Osman et al., 2012), the Four Systems Anxiety Questionnaire (Asghari et al., 2008), the Perceived Stress Scale (Osman et al., 2012), the Rosenberg Self-Esteem Scale (Sinclair et al., 2011), among many others.

The current study thus addresses this perspective of empirical external validation of the French DASS-21 which is pioneering as to date there is no reported study on the concurrent and divergent validities of the DASS-21 in adolescent samples.

Introduction 140


METHOD

PARTICIPANTS

Alongside the French DASS-21, the 1002 participants also responded to three different self-report measures of anxiety, depression, and stress adapted for the French population. Detail of these measures is provided below. The questionnaire set for each participant was randomly arranged in order to control for order effects.

MEASURES

The French RCMAS30 (Reynolds & Richmond, 1999)

Further to the theoretical and empirical foundations of the Revised Children's Manifest Anxiety Scales (RCMAS; Reynolds & Richmond, 1997) (already mentioned in Chapter One section 1.3.6), this instrument was chosen as it is brief and easy to administer for evaluating the level and nature of anxiety in children and adolescents aged between 6 and 19 years. Its 37 items make up the four subscales: physiological anxiety which includes 10 items associated with somatic manifestations of anxiety such as difficulties to fall asleep, nausea or fatigue; worry/oversensitivity with 11 items related to obsessions

accompanied

by

fears

of

being

isolated;

social

concerns/concentration with 7 items associated with school difficulties, 30

See Appendix P

141


uncomfortable thoughts with a social or interpersonal component, difficulties of attention and concentration; and finally, a lie scale which consists of 9 items to detect the tendency to consent, social desirability and falsification. The participant responds to each item with either “Yes” or “No”.

Results from several studies have demonstrated the RCMAS to possess adequate reliability, construct and concurrent validities (Muris, Merckelbach, Ollendick, King, & Bogie, 2002; White & Farrell, 2001). Furthermore, its empirical qualities have been also established in many languages, including Spanish and French (Ferrando, 1994; Turgeon & Chartrand, 2003). Cronbach’s alphas range from .59 to .76 in the French adaptation (Reynolds & Richmond, 1999).

The French MDIC31 (Berndt & Kaiser, 1999)

The theoretical premise of the Multiscore Depression Inventory for Children (MDIC, Berndt & Kaiser, 1996) has already been mentioned in Chapter One (section 1.2.8). The MDIC was selected because it is a reliable and valid measure of depressive symptomatology in children and adolescents aged between 8 and 17 years. The 79 true/false items are distributed across eight subscales: anxiety (physical and cognitive), self-esteem, social introversion (tendency to withdraw from social situations), instrumental helplessness (perceived capacity to cope with social situations), sad mood (perceived affective state), pessimism (perception of future), low energy 31

See Appendix J

Method 142


(intensity of cognitive and physical capacities), and defiance (behavioural problems). Empirical qualities of the MDIC include alpha coefficients ranging between .70 and .94 for all scales. Concurrent validity of the French MDIC has been established with other scales including the French RCMAS.

The French CISS32 (Endler & Parker, 1998)

The French adaptation of the Coping Inventory for Stressful Situations (CISS; Endler & Parker, 1990) was utilised as part of this research study because it was developed on the premise of the foregoing transactional stress model which emphasises the interaction between stressors and ways in which individuals respond to stressors (see Chapter One section 1.1.4). The CISS can be administered to individuals as from the age of 13. The 48 items assess three dimensions, task-oriented, emotion-focused, and avoidant coping responses to stressful circumstances. Items on the task-oriented scale aim at evaluating problem-solving through concrete behavioural approaches in order to change the situation. The emotion-focused scale assesses how the respondent emotionally deals with feelings of anger and tension in stressful situations. Finally, the avoidant scale evaluates one’s capacity to distract oneself from thinking about the stressful situations. The avoidant scale can be further divided into two subscales, namely social diversion, and distraction. Respondents rate each item on a 5-point Likert scale ranging from 1 (not at all) to 5 (very much).

32

See Appendix Q

Method 143


Internal consistency was estimated to be above .73 for each subscale in community samples, concurrent and convergent validities were found to be adequate with other psychometrically sound measures in non-clinical and clinical samples, and test-retest reliability was above .60 for each scale (Harkness, Tellegen, & Waller, 1995; Clark & Watson, 1991).

STATISTICAL ANALYSES

All statistical analyses were calculated using SPSS.

Initially, Pearson

product-moment correlations were calculated between the three DASS-21 scores and subscale scores on the MDIC, RCMAS, and the CISS. Thereafter, an exploratory factor analysis on the scales of these measures was conducted to strengthen further the external validity of the French DASS-21.

Method 144


RESULTS

DESCRIPTIVE STATISTICS

The means and standard deviations for each scale are presented in Table 12. Table 12: Descriptive statistics for scales of DASS-21, RCMAS, CISS & MDIC

Scale

Mean

SD

DASS-21 Depression

13.2

9.5

DASS-21 Anxiety

11.1

8.3

DASS-21 Stress

14.1

9.2

RCMAS Total

13.0

6.1

RCMAS Physiological Anxiety

3.9

2.3

RCMAS Worry/hypersensitivity

5.9

2.8

RCMAS Social concern/concentration 3.2

2.1

RCMAS Lie

4.5

2.3

CISS Task-oriented

51.7

12.2

CISS Emotion-focused

45.2

13.1

CISS Avoidance

47.4

13.8

CISS Distraction

22.9

7.6

CISS Social diversion

15.2

5.2

19.7

13.9

MDIC Anxiety

4.4

2.7

MDIC Self-esteem

1.8

2.0

MDIC Sad mood

2.2

2.4

MDIC Instrumental help

2.2

2.4

MDIC Social introversion

1.3

1.7

MDIC Low energy

2.7

2.0

MDIC Pessimism

2.4

2.2

MDIC Provocation

3.1

2.5

MDIC Suicide

.1

.3

MDIC Total

Results 145


CONCURRENT AND DIVERGENT VALIDITIES

Correlations between the three scales of the French DASS-21 and the scales and subscales of the RCMAS, CISS and MDIC are presented in Table 16.

The DASS-21 depression scale correlated significantly with the total scale of the MDIC with r = .62 (p< .05). A significant relationship was also obtained between the DASS-21 anxiety scale and the total scale of the RCMAS, r = .57 (p< .05). Similarly, the CISS emotion-focused scale, which is similar in content to the DASS-21 stress scale, significantly correlated with the latter scale with r =.53 (p

Validation of the

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