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Mukhtar & Tian

Original paper

Exploratory and confirmatory factor validation and psychometric properties of the Beck Depression Inventory for Malays (BDI-Malay) in Malaysia Firdaus Mukhtar* and Tian PS Oei** *School of Health Sciences, Universiti Sains Malaysia, Kelantan, Malaysia **School of Psychology, University of Queensland, Brisbane, Australia

Abstract The Beck Depression Inventory (BDI) has been shown to have good psychometric properties in Western and non-Western populations for the past 40 years. The present study reported on the factor structures and provided evidence of the psychometric properties of the BDI for the Malays in Malaysia. A total of 1090 Malays in four samples (students, general community, general medical patients, and patients with major depressive disorders) were recruited in this study. They completed a battery of questionnaires that included symptoms, cognition and quality of life measures. Twofactors of the BDI-Malay namely Cognitive/Affective and Somatic/Vegetative were extracted from Exploratory Factor Analysis (EFA) and were confirmed through Confirmatory Factor Analysis (CFA). Internal consistency (Cronbach’s α) ranging from = .71 to .91 and validity of the BDI-Malay were satisfactory. The BDI-Malay can be used with confidence as an instrument to measure levels of depression for Malays in Malaysia. Keywords: Beck Depression Inventory, Malaysia, psychometric, confirmatory factor analysis depression in clinical and research Introduction domains for the past 40 years 4, 5. Although it was originally developed for clinically Mood disorder is one of the most prevalent depressed patients, its validity and psychiatric disorders, involving 1 reliability has been demonstrated within approximately 3.6% of the population . non-clinical samples, such as university One of the reasons why depression is and the general undergraduates6 under-recognised and under-treated is 7 community . because of a lack of validated instruments to assess this mental health condition that In a meta-analysis, previous study revealed are particularly essential as a treatment high internal consistencies of the BDI outcome measure. Empirical studies have (psychiatric patients = 0.86; nonindicated that the Beck Depression psychiatric sample = 0.81) with an alpha Inventory (BDI) has been established mean of 0.87 4. Furthermore, findings from worldwide, both in Western and Eastern test-retest reliability analyses also populations, to measure the symptoms of provided support for the reliability of the depression. To date, no study has been BDI; specifically, studies that used this reported on the psychometric and factor procedure revealed correlation coefficients structure of the BDI among Malays in of 0.60 and 0.77 8, 9. Along with evidence Malaysia. of reliability, a growing number of studies 2, 3 have reported indications of discriminant has been one of the leading The BDI validity 10 and concurrent validity 11. instruments for measuring level of

MJP Online Early However, results on the factorial structure of the BDI are less clear. There are studies discovered three dimensions of the BDI (negative attitude, performance difficulty and somatic elements) 12, 13, while one study found six factors related to the BDI in the non-clinical population 14. Inconsistencies were also revealed in a number of other studies within nonWestern samples for instances found four factors 11 could be extracted from the BDI (alarm, irritability, somatic symptoms, and depression and retardation) and two factors of the BDI among the Chinese population. 15 In the case of Malaysia, even though the BDI has been validated in a study of urological patients 16, the majority of these patients were Chinese and this limited the instrument as a reliable and valid measure in Malaysia, in particular for Malays. Furthermore, their study reported on internal consistency, test-retest reliability, and specificity and sensitivity of the BDI but gave no evidence of using exploratory and confirmatory analysis to confirm its psychometric properties and factor structure. It is therefore the intention of this paper to report on the psychometric properties and validity of the BDI with Malays. Thus, in light of the previous literature, the main aims of the present study were to (a) examine the factor structure of the BDI for Malays in Malaysia, and (b) provide evidence of the psychometric properties of this scale so that the BDI may be used with confidence in Malaysia, particularly for Malays. Method Participants

Mukhtar & Tian A total of 1090 participants were recruited for this study. The sample consisted of 315 students (28.9%), 495 members of the general community (45.4%), 167 patients from a primary care unit (15.3%), and 113 patients diagnosed with major depressive disorder from a psychiatric clinic (10.4%); 820 participants were female (75.2%), and the participant’s ages ranged from 18 to 63 years, with a mean of 26. The educational backgrounds of the participants included (a) high school certificate (47.6%), (b) diploma/certificate level (17.1%) and a university degree (32.5%); 1% of the total number of participants had only completed primary school and 1.8% did not specify their level of education. Measures Demographic data Background information, including age, gender, and level of education were collected along with other data. Beck Depression Inventory-Malay The BDI-Malay is a translated version of the original BDI 3 with 21 items that provide an indication of the level of depressed mood. Participants respond to questions in relation to how they have felt over the past week, with higher scores indicating more severe depression. The 21 items of the BDI are divided into two subscales: a cognitive/affective subscale formed from the first 13 items, and a somatic/performance subscale formed from the last eight items. The full scale is considered to have strong psychometric properties, with mean alpha coefficient exceeding 0.90 and test-retest reliability of 0.80. 4

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Automatic Malay

Mukhtar & Tian

Thoughts

Questionnaire-

The 17 items of the Automatic Thoughts Questionnaire-Malay (ATQ-Malay) 17, is a translated version of the original ATQ 18 with 30 items that measure the frequency of negative automatic thoughts. Respondents rate the frequency of the 30 negative thoughts on a 1 to 5 scale. For instance, how frequently negative automatic thoughts such as “I’m a loser” have occurred in the past week; higher scores indicate increased severity of negative thoughts. Internal consistency is strong, ranging between 0.83 and 0.93, there is a moderately strong relationship (r > 0.60) between the ATQ and depressive symptomatology, and the scales were able to differentiate between depressed and non-depressed samples 17. Dysfunctional Attitude Scale-Malay (Oei & Mukhtar, 2008) The 19 items of the Dysfunctional Attitude Scale-Malay (DAS-Malay) 19 is a translated version of the original DAS 20 with 40 items that require responses ranging from “totally agree” to “totally disagree”, with seven options for each statement. The scale has acceptable internal consistency and concurrent validity and was able to discriminate between depressed and non-depressed samples 19; lower scores indicate less dysfunctional attitudes. Zung Depression Malay

Self-Rating

Scale-

The Zung Depression Self-Rating ScaleMalay (Zung SDS-Malay) is a translated

version of the original Zung SDS 21, which was designed for assessing depression in patients whose primary diagnosis was of a depressive disorder. The 20 items address each of the four most commonly found characteristics of depression: its pervasive effect, its physiological equivalents, other disturbances, and psychomotor effects. Range of total score is from 20 to 80, within which most people with depression score between 50 and 69, while a score of 70 and above indicates severe depression 21. WHO Quality of Life-BREF The WHO Quality of Life-BREF (WHOQOL-BREF) version in Bahasa Malaysia (WHOQOL-BREF Malay) 22, consisting of 26 items, has been validated in Malaysia, with indications of good discriminant validity, construct validity, internal consistency (0.64 to 0.80) and test-retest reliability (0.49 to 0.88). The scale is a valid and reliable assessment of quality of life, especially for those with illness. Four domains that can be extracted from WHOQOL-BREF are physical and psychological health, social, and environment, which assesses general quality of life. Beck Hopelessness Scale-Malay The Beck Hopelessness Scale-Malay (BHS-Malay) is a translated version of the original BHS 23 with a 20-item scale for measuring negative attitudes about the future. The scale’s manual claims internal consistency ranging from 0.82 to 0.93 and a test-retest reliability of 0.69 23.

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Procedure Student sample. The subjects in this study were 315 undergraduate students from various faculties of two universities. Subjects participated voluntarily in this study to partially satisfy a research requirement of their course. All of the data for this study were collected through group administrators. Each subject was provided with a battery of questionnaires as described above, with an explanation and accompanying directions for their use. There were a number of non-Malay students who participated in this study; however their data was not included in the analysis so as to ensure that the conditions of this study were met. General community sample. Members of the general public participated in this study by completing questionnaires that had been randomly distributed in public places by research assistants, and returning them in envelopes supplied. Medical patients sample. The Malay medical patients recruited in this study were from primary care clinics, an obesity clinic, Ear, Nose and Throat (ENT) clinics, and community care clinics. The medical patients participated in this study by completing questionnaires that had been distributed by research assistants, and returning them in envelopes supplied. Subjects in all categories were discarded from the study if they were current drug or alcohol abusers, had a history of organically based cognitive dysfunction, demonstrated reading difficulties, were not fluent in Bahasa Malaysia, or were not ethnic Malays. Patients with major depressive disorders. Malay patients with depression were invited via mail, phone or through referral from psychiatrists who had been informed of the study. A letter of invitation and

Mukhtar & Tian information regarding the study was provided and those participants who were willing to participate presented at the psychiatric clinic for the intake procedure assessment. The first author of this study, further evaluated the early diagnosis of major depressive disorder using a structured clinical interview from the Diagnosis and Statistical Manual of Mental Disorder- Fourth Edition (DSMIV) to ascertain participants’ eligibility. Participants were included if they were diagnosed as suffering from major depression or dysthymia as defined by the DSM-IV. Patients were excluded if their depression was secondary to another major psychiatric disorder (e.g., schizophrenia), if they were currently abusing drugs or alcohol, had a history of organically based cognitive dysfunction, demonstrated reading difficulties, or were not fluent in Bahasa Malaysia. Translating and back-translating procedure. In this study, the Malay version of all instruments (except WHOQOLBREF) was translated using backtranslating procedures by four psychologists with at least a Master’s level of study and bilingual expertise. A professional language interpreter was recruited to proofread the translated questionnaires to ensure their overall suitability and to resolve issues of word ambiguity after translation. The backtranslated versions were similar to the original versions and to each other. Minor differences in colloquial expressions in both languages were reconciled. Signed informed consent was obtained from all participants in the study before they undertook the assessment. Ethical approval was sought from the research ethics committee of the Ministry of Health of Malaysia and all the hospitals and institutions that participated in this study.

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Statistical analyses Statistical Program Social Sciences version 14.0 and AMOS version 6.0 were used to analyse data in this study. A number of statistical procedures were used. Descriptive statistics were used for data screening. In addition, Cronbach’s alpha coefficients (α) were computed to evaluate the reliability of the questionnaire, and correlations were calculated to examine the concurrent validity of the BDI, using the total sample. Discriminant analyses were used to evaluate the discriminant validity, specificity and sensitivity of the BDIMalay scores. The CFA model fit was evaluated using multiple fit indices 24. The indices selected were the chi-square statistics (χ ²), the comparative fit index (CFI) 25, the Standardized Root Mean-square (SRMR) 26 , the goodness of fit index (GFI), the Root Mean Square Error of Approximation (RMSEA) 27, and the Akaike Information Criteria (AIC) 28. A good model fit is indicated by values of 0.90 or higher for the CFI and GFI. For the SRMR and RMSEA, values of 0.05 or lower indicate a close fit, while values less than 0.08 indicate an acceptable fit 27 and the one with the lowest AIC is preferred in model comparison 24. Results for the BDI-Malay Assumption testing Prior to conducting the primary analyses, the data were examined for accuracy, missing values, outliers and multivariate assumptions. The number of missing values was minimal (