Psychometric Properties of the Self-Concept

European Journal of Psychological A. Ghaderi: ©2005Hogrefe&HuberPubli Assessment Self-Con2005;21(2):139–1 cept Questionnaire shers 46

Psychometric Properties of the Self-Concept Questionnaire Ata Ghaderi Department of Psychology, Uppsala University, Uppsala, Sweden Abstract. The aim of the present study was to examine the psychometric properties of the Swedish version of the Self-Concept Questionnaire (SCQ). Data from three samples were used: (1) a representative sample of women (18–30 years) from the general population of Sweden (n = 826), (2) a student sample (n = 124), and (3) a clinical sample (n = 43) comprising patients with eating disorders. Principal component analysis (PCA) resulted in a five-factor solution that accounted for 46% of the variance. The students responded to the SCQ twice within 3 weeks and the SCQ showed high test-retest reliability with no significant differences in the mean total scores between the first and second set of responses. In all the samples, the SCQ showed very high internal consistency, ranging from .94 to .97. The SCQ showed high validity as it correlated highly with Rosenberg scale of self-esteem in the patient group, and the Ineffectiveness subscale of the Eating Disorders Inventory in the student sample. Furthermore, the SCQ showed high discriminant validity by differentiating clinical from non-clinical subjects. In summary, the Swedish version of SCQ has been shown to possess good concurrent and discriminant validity as well as high reliability. Given its multidimensionality and encouraging preliminary psychometric properties, the SCQ can be a valuable instrument in assessing self-esteem in clinical settings as well as in the studies of the general population. Keywords: Self-esteem, reliability, validity, self-concept, assessment

Self-esteem can be defined as the sense of contentment and self-acceptance that results from a person’s appraisal of one’s own worth, attractiveness, competence, and ability to satisfy one’s aspirations (Robson, 1989). The association between self-esteem and psychiatric disorders such as eating disorders has been demonstrated in numerous studies. In a series of community-based casecontrol studies, low self-esteem was shown to be a significant risk factor for both bulimia nervosa (Fairburn, Welch, Doll, Davies, & O’Connor, 1997) and anorexia nervosa (Fairburn, Cooper, Doll, & Welch, 1999). Prospective research on risk factors for eating disorders among schoolgirls (e.g., Button, Sonuga Barke, Davies, & Thompson, 1996; Calam & Waller, 1998) and in the general population (e.g., Ghaderi & Scott, 2001) has also shown that low self-esteem constitutes a risk factor for developing eating disorders or unhealthy eating attitudes (Wood, Waller, & Gowers, 1994). There is also extensive empirical data on the presence of low self-esteem in dieting disordered patients (Griffits et al., 1991), as well as in other psychiatric disorders such as depression (e.g., de-Man, Gutierrez, & Sterk, 2001), psychosis (e.g., Krabbendam et al., 2002), suicidality (e.g., Vilhjalmsson, Krisjansdottir, & Sveinbjarnardottir, 1998), and © 2005 Hogrefe & Huber Publishers

anxiety disorders (e.g., Miller, Kreitman, Ingham, & Sashidharan, 1989). Consequently, accurate assessment of self-esteem is important, especially in prevention interventions and for identifying at-risk groups, given the role of low self-esteem in the processes that set the scene for psychiatric disorders. Although there is already a widely used instrument for the assessment of self-esteem (i.e., Rosenberg’s self-esteem scale) it constitutes a narrow, one-dimensional scale that despite excellent psychometric properties does not capture the complexity of self-esteem. Assessing the inherent dimensions of self-esteem (i.e., the subjective sense of significance, worthiness, appearance and social acceptability, competence, resilience and determination, control over personal destiny, and value of existence) can improve the predictive power of the concept in clinical settings as well as studies in the general population. Given this assumption, an instrument capturing the complex nature of self-esteem is most desirable. The most common instrument for assessing self-esteem is Rosenberg’s Scale for self-esteem (Rosenberg, 1979). However, a variety of other measures such as the Coopersmith Self-Esteem Inventory (Ahmed, Valliant, & Swindle, 1985) are also available. For a critical review of the theory and assessment of self-esteem see European Journal of Psychological Assessment 2005; 21(2):139–146 DOI 10.1027/1015-5759.18.1.139

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Fisher (1997) since a systematic review of all the available measures are beyond the scope of this paper. The present study aims at describing the psychometric properties of the Swedish version of the Self-Concept Questionnaire (SCQ; Robson, 1989) which was devised to address the shortcomings of the currently available scales of self-esteem, including Rosenberg’s scale. The SCQ has proved to have good reliability (Cronbach’s α of .89) and high validity (clinical validity of .70) (Robson, 1989). The only independent psychometric evaluation of the SCQ (Addeo, Greene, & Geisser, 1994) provided support for regarding the SCQ as a reliable and valid instrument for assessing self-esteem. The reliability of the SCQ in terms of test-retest reliability and internal consistency was investigated in the present study. Convergent and discriminative validity of the SCQ was investigated by comparing the SCQ with other measures of self-esteem, and by analyzing its ability to distinguish different subsamples of subjects along some criterion variables characterized by different levels of self-esteem. A replication of the Robson’s factor solution was not expected because self-esteem is a completely verbal construction. Its definition, apart from problems of arriving at a consensus in the scientific community, as discussed by Robson (Robson, 1988), is highly dependent on verbal behavior (Hayes, Barnes-Holmes, & Roche, 2001) and social norms (Wells & Marwell, 1976) in each soci-

ety. This should, by definition, result in at least some differences in different contexts (i.e., languages and societies). However, it was expected that major parts of Robson’s factor solution would be reproduced if the instrument is to be regarded as a valid measure of a construction that can be used in scientific contexts. Given the assumptions above, and methodological issues, confirmatory factor analysis was not used.

Method Participants A series of questionnaires were administered to the following three samples: (1) a nationwide representative sample of 826 women between the ages of 18 and 30 that were assessed twice, with a two-year interval, (2) a clinical sample (n = 43), consisting of patients with bulimia nervosa and eating disorders not otherwise specified, and (3) a nonclinical sample of undergraduate psychology students (n = 124). The national sample was recruited for a longitudinal study on the risk factors for the development of eating disorders. As has been shown (Ghaderi & Scott, 1999), this sample can be considered as representative for women between 18 and 30 years in Sweden. The characteristics of this sample are shown in Table 1.

Table 1. Demographic characteristics of the samples.

Age: mean (SD) Marital status Married Divorced/separated Living together Single Education Primary school, uncompleted Primary school, completed High school Vocational education College/university Occupation Employed Student/at school Unemployed On sick pay/other Diagnoses Bulimia nervosa EDNOS1 Body mass index: mean (SD) 1

Nationwide sample, T1 N = 826 % (n) 23.7 (3.7)

Nationwide sample, T2 N = 826 % (n) 25.6 (3.7)

Clinical sample N = 43 % (n) 27.1 (9.9)

12.5 1.1 40.2 46.3

(103) (9) (332) (382)

16.3 1.7 42.5 39.5

(134) (14) (349) (324)

9 2 19 70

(4) (1) (8) (30)

18 3 27 53

(22) (4) (33) (65)

3.3 13.6 64.9 3.3 15.0

(27) (112) (536) (27) (124)

.4 6.2 65.7 4.3 23.5

(3) (51) (539) (35) (193)

2 14 63 5 16

(1) (6) (27) (2) (7)

– – 80 – 20

(99)

42.9 42.0 13.2 2

(354) (347) (109) (16)

58.7 30.4 9.6 1.3

(485) (251) (79) (11)

21 63 7 9

(9) (27) (3) (4)

– 100 – –

11 32 24.5

(26) (74) (5.9)

1.7 0.9 22.6

(14) (7) (3.8)

1.3 1.8 23.1

(11) (15) (4.2)

Student sample N = 124 % (n) 28.8 (6.3)

1.6 2.4 22.2

(25)

(100)

(2) (3) (4.1)

EDNOS: Eating disorders not otherwise specified (i.e., subthreshold bulimia nervosa or anorexia nervosa, and binge eating disorder).

European Journal of Psychological Assessment 2005; 21(2):139–146

© 2005 Hogrefe & Huber Publishers


The clinical sample consisted of 43 women who were recruited for participation in a study examining the efficacy of self-help for bulimia nervosa and eating disorders not otherwise specified (see Table 1). The student sample consisted of 124 students (81% females, and 19% males) recruited from a master’s program in clinical psychology. The characteristics of the sample are shown in Table 1. The students’ body mass index (BMI) was determined from self-reported height and weight. Validity of self-reported measures of height and weight has been confirmed against anthropometric measures (Whitaker et al., 1990).

Measures Self-Concept Questionnaire (SCQ) The SCQ is a self-report scale measuring self-esteem (Robson, 1989). It consists of 30 items (e.g., “I have control over my life,” “I feel emotionally mature,” “I can like myself even if others don’t”). The items are based on seven components of self-esteem, according to theoretical and empirical information reviewed by Robson (1988). The scoring is performed on an eight-point scale, ranging from completely disagree to completely agree. The SCQ has been proven to have good reliability (Cronbach’s α of .89) and good validity (clinical validity of .70; i.e., the correlation between the scores on the SCQ and estimates of self-esteem made by experienced clinicians on a 10-point visual analog scale for a sample of psychiatric patients; Robson, 1989). The SCQ was translated into Swedish and then back-translated into English in order to ensure accuracy. After the retranslation into English, the questionnaire was almost totally identical to the original version, after some minor revisions, and seemed to measure the same constructs. Rosenberg Self-Esteem Scale (RSE) The RSE scale is a widely used instrument for measuring global self-esteem. It consists of 10 items with a fourpoint response scale, from strongly agree to strongly disagree. The RSE yields a seven-point scale (0–6) with higher scores indicating lower self-esteem. The RSE has excellent psychometric properties (Kernis, Grannemann, & Barclay, 1989; Rosenberg, 1979). Eating Disorders Inventory-2 (EDI-2) The EDI-2 is a widely used self-report measure of symptoms of eating disorders. It consists of 91 questions, 64 of which are from the original version of the EDI (Garner, Olmsted, & Polivy, 1984), which provides standardized subscales on eight dimensions that are clinically rel© 2005 Hogrefe & Huber Publishers

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evant to eating disorders (ED). The additional 27 items add three new constructs that form the EDI provisional subscales (Garner, 1991). The questions are answered on a six-point scale from always to never. Item examples are “I feel ineffective in the world,” “I eat when I am upset,” and “I feel inadequate.” The Swedish version of the EDI has been validated (Norring & Sohlberg, 1988) and normative information for the Swedish population of students and patients is available. The reliability and validity of the EDI has been established in several studies, and corroborated in Swedish studies (Nevonen & Broberg, 2001; Norring & Sohlberg, 1988). In the present study, as in the Swedish validation studies, the participants’ responses to the EDI were scored according to the instructions in the original manual (Garner, Olmsed, & Polivy, 1983), by which the most pathological responses score 3 points, the adjacent response score 2, and the next 1, with the remaining three scoring 0 points. The ineffectiveness subscale of the EDI-2 was used to assess the validity of the SCQ. Eating Disorders Examination (EDE) The EDE (Fairburn & Cooper, 1993) is a semistructured interview that assesses the two key behavioral aspects of eating disorders and provides operationally defined eating disorder diagnoses. The EDE was used to establish the diagnoses for the clinical sample. The Big-Five Mini-Markers Mini-Markers is a shortened version of Goldberg’s unipolar Big-Five Markers (Goldberg, 1992) developed by Saucier (Saucier, 1994). It consists of 40 adjective markers, and compared with the original scale (Goldberg’s 100-item scale) it is characterized by less use of difficult items, lower interscale correlations, and somewhat higher interitem correlations, although α reliabilities are somewhat lower (Saucier, 1994).

Procedure A composite of questionnaires, including the SCQ, was sent out to the participants in the national sample. They were asked to participate in a nationwide study on risk factors for eating disorders and to fill in and return the questionnaires to the authors. They were also informed that ther would be a follow up after 2 years. Thus, the sample responded twice to the SCQ. In the clinical sample, several questionnaires, including the SCQ and EDI-2, were sent out to the potential participants in the treatment studies after a comprehensive phone screening. When the questionnaires were European Journal of Psychological Assessment 2005; 21(2):139–146

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filled in and returned, the patients were scheduled for an assessment interview by means of the EDE to establish the eating disorders diagnoses. Those who did not fulfill the diagnostic criteria for bulimia nervosa or eating disorders not otherwise specified according to the DSM-IV (American Psychiatric Association, 1994; i.e., subthreshold bulimia nervosa and anorexia nervosa, and threshold and subthreshold binge eating disorder) were then excluded. In the student sample, the students were given course credits for anonymously responding to a composite of questionnaires, including the SCQ, that would be followed by another set of questionnaires after 2 weeks. The first set of questionnaires were returned by 144 students, and 124 of them also responded to the second.

Statistical Analyses Principal component analysis (PCA) was used to examine the factor structure of the SCQ. In addition to investigating the results of the Scree test and Kaiser-Guttman Criterion for deciding on the number of factors to extract, parallel analysis (Glorfeld, 1995; Horn, 1965) was applied using the SPSS syntax suggested by O’Conner (2000) and an independent program by Watkins (2000). To assess the test-retest reliability, the students’ responses to the SCQ at the two time points were compared using Pearson’s correlation, and t-test. Pearson’s correlation was used to test the convergence between the SCQ and the ineffectiveness subscale of the EDI-2, and Rosenberg’s self-esteem scale. Internal consistency was measured using Cronbach’s α. Split-half reliability has not been reported here because Cronbach’s α may be considered as a generalized split-half reliability.

Results Factor Structure of the SCQ A PCA was conducted on the data from first wave of the nationwide sample. It resulted in six factors, indicated by the Scree test and the Kaiser Criterion (i.e., only factors with eigenvalues greater than 1 were retained). However, only one item (No. 6: I am not embarrassed to let people know my opinion) loaded on the sixth factor. Consequently, it was removed, and the five-factor solution, which is the best interpretable solution, was retained. Then the communalities based on the five-factor solution and the corresponding multiple R2 for each item were investigated in order to see whether there were any instances where the R2 was high and the corresponding communality was low. This would suggest the need to European Journal of Psychological Assessment 2005; 21(2):139–146

retain one or more additional factors. However, this was not the case for any of the items. These five factors together explained 45.8% of the variance. Parallel analysis also suggested a five-factor solution as most appropriate. It should be mentioned, however, that the eigenvalues in item-level raw data based on dichotomous or Likert response scales cannot be meaningfully compared to the eigenvalues from parallel analyses based on normally distributed random numbers. Instead, one should determine the number of factors or components by first finding the eigenvalues for the raw-data matrix of tetrachoric or polychoric correlations, and then compare these eigenvalues to those that are produced by the computergenerated random data (O’Connor, 2000). Consequently, the subsequent factor analysis should be conducted on the raw-data matrix of tetrachoric or polychoric correlations and not on Pearson correlations. However, since the parallel analysis resulted in the same factor solution as the Kaiser criterion, the PCA was carried out using standard procedures. Using the varimax orthogonal rotation, each item loaded heavily on one single factor, and low on other factors. The factor loadings for the rotated factor structure of the SCQ items are presented in Table 2. As seen in Table 2, the first factor, named Contentment and Worthiness embraces five of the six items that were part of the same factor in the factor analysis made by Robson (2002) who constructed the SCQ. The content of the other three items that loaded on this first factor focuses on contentment and worthiness. The second factor was named Attractiveness and Approval by Others since it consisted of exactly the same items as those loading on a corresponding factor in the analysis by Robson. The third factor is a new constellation, named Determinism. It consists of four items, two of which (Items 14 and 22) were omitted in the factor analysis by Robson. In constructing the SCQ, Robson (1989) gathered questions that were supposed to be part of the following seven domains of self-esteem: (1) subjective sense of significance, (2) worthiness, (3) appearance and social acceptability, (4) competence, (5) resilience and determination, (6) control over personal destiny, and (7) the value of existence. Items 14 (When I am successful, there’s usually a lot of luck involved) and 22 (There’s a lot of truth in saying “what will be, will be”), which load on Factor 3, are typical examples of deterministic thinking while Items 11 and 14 are more ambiguous. The fourth factor was called Confidence and Value of Existence because five (Items 4, 7, 8, 20, and 25) of the six items that loaded on a similar factor (Value of Existence) in a previous analysis (Robson, 2002) were present on this factor. The other items loading on this factor are about control and confidence. © 2005 Hogrefe & Huber Publishers


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Table 2. Varimax rotated five-factor structure of the SCQ items1.

Items SCQ 5 * SCQ17 * SCQ18 SCQ19 * SCQ21 * SCQ26 SCQ27 * SCQ29 SCQ 2 * SCQ 9 * SCQ15 * SCQ23 * SCQ30 * SCQ11 SCQ13 SCQ14 SCQ22 SCQ 1 SCQ 3 SCQ 4 * SCQ 7 * SCQ 8 * SCQ10 SCQ20 * SCQ24 SCQ25 * SCQ28 SCQ12 SCQ16 Variance

Factor 1: Contentment and worthiness There are lots of things I’d change about myself if I could. I often feel humiliated. I can usually make up my mind and stick to it. Everyone else seems much more confidant and contented than me. I often worry about what other people are thinking about me. I feel emotionally mature. When people criticize me I often feel helpless and second-rate. I can like myself even when others don’t. Factor 2: Attractiveness, approval by others I’m easy to like. Most people find me reasonably attractive. I have a pleasant personality. I look awful these days. Those who know me well are fond of me. Factor 3: Determinism and significance Most people would take advantage of me if they could. It would be boring if I talked about myself. When I am successful, there’s usually a lot of luck involved. There’s a lot of truth in saying “what will be, will be.” Factor 4: Confidence and value of existence I have control over my own life. I never feel down in the dumps for very long. I can never seem to achieve anything worthwhile. I don’t care what happens to me. I seem to be very unlucky. I’m glad I am who I am. Even when I quite enjoy myself there doesn’t seem much purpose to it all. If I really try, I can overcome most of my problems. It’s pretty tough to be me. When progress is difficult, I often find myself thinking it’s not worth the effort. Factor 5: Resilience I am a reliable person. If a task is difficult that just makes me all the more determined.

Factor loadings F3 F4

F1

F2

F5

–.52 –.41 .57 –.57 –.67 .36 –.67 .57

.32 –.13 .01 –.24 –.15 –.15 –.08 –.17

.11 –.33 .12 –.31 –.25 –.01 –.21 .06

–.27 .33 .14 .32 .15 .23 .18 .29

.16 .06 .26 –.06 .06 .30 .19 .01

–.00 .18 .11 .29 .18

.57 .70 .68 –.44 .52

–.13 –.03 –.09 –.22 –.03

.19 .01 .18 .34 .19

.28 –.19 .24 –.20 .25

.06 .24 .15 –.03

–.07 –.23 –.25 .15

–.47 –.51 –.60 –.62

.21 .03 .08 .09

.36 –.01 .12 .01

.23 .27 .27 –.10 .08 .34 .23 .12 .44 .25

–.24 .00 –.26 –.22 –.10 –.41 –.11 –.10 –.12 .02

–.02 .08 –.39 –.25 –.38 –.08 –.18 .11 –.09 –.24

.63 .62 –.52 –.58 –.53 .54 –.69 .48 –.51 –.56

.13 .06 .04 .16 –.12 .07 .10 .16 –.04 .09

–.03 .29 .12

–.18 –.03 .09

–.09 –.04 .07

.11 .04 .13

.71 .49 .05

1

n = 729, case-wise deletion. Items marked with an * were reported to load on the same factor in the factor analysis conducted by Robson (P. Robson, 2002).

The last factor consisted of Item 12 (I am a reliable person) and 16 (If a task is difficult that just makes me all the more determined). This factor was named Resilience.

Validation of the Factor Structure of the SCQ In order to validate the resulting factor structure, the analysis was repeated with the same sample that was followed up after two years (n = 826), and the first and second halves of these samples, as well as the student sample (n = 124) that was assessed twice with 3 weeks © 2005 Hogrefe & Huber Publishers

in between. The PCAs again resulted in six factors with the population sample, with the last factor consisting of one single item as in the previous first analysis. The factor analyses in the student sample resulted in five factors. Across these validation analyses, almost all of the items loaded on the same factors. The exceptions were Item 6 (I am not embarrassed to let people know my opinion), Item 13 (It would be boring if I talked about myself), Item 17 (I feel often humiliated), and Item 26 (I feel emotionally mature). These items often loaded moderately on several factors, which is not surprising given their content. European Journal of Psychological Assessment 2005; 21(2):139–146

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Table 3. Intercorrelations between the factor scores, the SCQ sum total, and the Emotional Stability subscale of the Big-5 MiniMarkers in the national study, and zero-order correlations between the SCQ factor scores, the RSE, and Ineffectiveness subscale of EDI in the student sample.

Factor score 1 Factor score 2 Factor score 3 Factor score 4 Factor score 5

SCQ (total) .49 .34 .38 .60 .17

Emotional stability3 .31 .09 .19 .37 .09

RSE1 –.59 –.25 –.39 –.51 –.26

EDI Ineffectiveness2 –.56 –.37 –.42 –.52 –.29

1

RSE: Rosenberg Scale for Self-esteem. 2EDI-Ineffectiveness subscale of the Eating Disorder Inventory (EDI). 3Emotional stability from the Big-Five Mini-Markers. All correlations were significant on at least the p < .05 level.

Intercorrelations Between Factor Scores and the SCQ Total The intercorrelations between the factor scores and the SCQ total ranged from moderate to high, with the exception of fifth factor, which showed a modest, albeit significant correlation (Table 3). The correlations between the SCQ factor scores and the Big-Five factor Emotional Stability in the national sample were modest to moderate. Although the second factor (i.e., Attractiveness and Approval by Others) was consistently reproducible in the validating factor analyses (i.e., analysis on the first or second half of the same sample, and other samples) the correlation between Factor 2 and the total SCQ remained at a moderate level (.32–.42). The fifth factor showed a higher correlation with the SCQ total in the patient sample compared to the sample from the general population, but the correlations remained at modest to moderate levels across the analyses. As Table 3 shows, all the factors of the SCQ correlated negatively with the RSE as expected, with zero order correlation ranging from –.25 to –.59. A similar pattern of correlations emerged when the correlations between the SCQ factor scores and the ineffectiveness subscale of the EDI (also measuring self-esteem) were calculated. The correlations between the factors of the SCQ with the RSE and the Ineffectiveness subscale of the EDI were very similar in the second wave of the assessment in the student sample.

The Reliability of the SCQ The students’ responses to the SCQ on both occasions were highly correlated r = .89 (p < .0001). This was also checked by means of the t-test, which showed no significant difference (t123 = –.80, p = .43) between the SCQ total scores from the first and second assessment point. The SCQ showed high homogeneity (Cronbach’s α of European Journal of Psychological Assessment 2005; 21(2):139–146

.89) in the first wave of the national sample, and the corresponding value when participants were followed up (after 2 years) was .91. In the student sample, the α was .86 and .89, respectively, for the first and second set of questionnaires answered by the students. In the clinical sample (n = 43) the α was .83.

Validity of the SCQ The SCQ total scores from both the first and second set of questionnaires in the student sample were used to study the convergent validity of the SCQ, by examining the correlation between the SCQ and the Rosenberg’s self-esteem scale (RSE). The Pearson correlation coefficients were r = –.65 (p < .0001) and r = –.80 (p < .0001) respectively. The corresponding correlation in the clinical sample (n = 43) was –.81 (p < .001). In addition, the relation between the SCQ and the ineffectiveness subscale of the EDI in the student sample and the clinical sample was also high: r = –.80 (p < .001) and r = –.78 (p < .001), respectively. Finally, the correlation between the SCQ total score and the Big-Five factor Emotional Stability in the national sample was .46 (p = .001), indicating that higher level of emotional stability (less neuroticism) accompanies higher self-esteem. A large number of empirical studies have shown that individuals with eating disorders report lower self-esteem compared to controls (e.g., Akan & Grilo, 1995; Button et al., 1996; Silverstone, 1990; Walters & Kendler, 1995). Evidence of the discriminant validity of the SCQ can be shown in differences in the SCQ scores between the clinical and nonclinical groups. In the national study, those who met the diagnostic criteria for eating disorders (n = 24) had significantly (F1,993 = 27.0, p = .0000003) lower scores on the SCQ (M = 130, SD = 22.5) compared to those without eating disorders (M = 152, SD = 20.4) (Ghaderi & Scott, 1999). The mean SCQ for the clinical sample in the present study was 125 (SD = 20.8), while the mean for the student sample was 155 (SD = 18.3) at the first assessment point, and 156 (SD = 19.4) at reassessment.

Discussion The results from the present study lend support for the reliability and validity of the Swedish version of the SCQ. The factor analyses clearly showed that the SCQ comprises several factors, and that a five-factor solution seems to be a reproducible and meaningful constellation. The five-factor solution accounted for 46% of the variance. The outcome resembles the findings from the factor analysis by the developer of the SCQ (Robson, 2002). The only independent study of the SCQ has been done © 2005 Hogrefe & Huber Publishers


by Addeo and colleagues (Addeo et al., 1994). The factor analysis by Addeo resulted in three factors that are largely in line with those factors extracted by Robson. Both Robson (1989), and Addeo and colleagues (1994) conducted a maximum likelihood factor analysis with oblimin (oblique) and equamax(orthogonal) rotations. In the present study, the first factor contained five of the six items that were part of the Contentment and Worthiness factor in Robson’s analysis, and several of them are in the corresponding factor in the study by Addeo et al. (1994). The second factor, Attractiveness and Approval by Others, converged completely with Robson’s analysis. The third factor, named Determinism, was a new factor. However, Robson chose items from seven domains of self-esteem, one of which was determinism. Especially, Items 14 and 22 in this third factor do load on an own factor consistently when the replicability of the factor solution has been examined repeatedly. In the fourth factor, labeled Confidence and Value of Existence, five of the six items from Value of Existence in the factor solution by Robson are included, as well as several items that were part of the Competence factor and Autonomous Self-Regard in Robson’s analysis. Finally, the last factor consists of only two items, of which Item 16 was the most robust in validation analyses. Because of its content, the factor was labeled Resilience. When compared to the findings by Robson (2002) and Addeo et al. (1994), the present factor structure seems to be a meaningful solution given the content of the items on each factor. As mentioned previously, some of the items were less consistent in the validating factor analyses, but the nature of the content of these items makes them vague. This might explain the inconsistency of these items in factor analyses, and the relatively moderate loading of these items on several factors in different analyses. Furthermore, inconsistent results could be due to different rotation criteria as well. The SCQ showed high convergent and discriminative validity as seen by the correlation between the SCQ and the RSE, and the ineffectiveness subscale of the EDI as well as the distinct differences in SCQ total scores between the clinical and nonclinical sample. In the study by Robson (1989), the correlation between the SCQ and the RSE in the clinical sample was .85. Addeo et al. (1994) reported a correlation of .84 among students. In the present study the corresponding correlation in the clinical sample was –.81 (the negative sign is because the original version of the RSE and coding was used where high scores indicate low self-esteem). In the student sample the correlation observed was between –.65 and –.80. Furthermore, the SCQ clearly differentiated the group of participants with and without eating disorders as seen from the results of the nationwide study. The pattern of © 2005 Hogrefe & Huber Publishers

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the intercorrelations of the dimensions of the SCQ in the nationwide sample suggests that the dimensions possess a moderate level of differential construct validity. Concerning the association between the SCQ factor scores and the Big-Five factor Emotional Stability, the very weak correlations between both the second and fifth factors and Emotional Stability were expected given the content of these factors and the theoretical construct of the Emotional Stability subscale of the Big-Five MiniMarkers. However, the correlation between the SCQ total score and Emotional Stability was much higher (r = .46), which indicates the complexity of the construct of self-esteem. Finally, the SCQ showed high reliability as shown by high test-retest reliability and internal consistency in terms of Cronbach’s α. The available data from the present and other studies support the conclusion that self-esteem is composed of several dimensions, and that SCQ is a reliable and valid instrument for assessing self-esteem. In summary, the findings from the present study confirm that Swedish version of the SCQ possesses good psychometric properties and thereby, it is recommended for assessing self-esteem both in clinical settings and in the studies in the general population. Acknowledgment This study was supported by the Sasakawa Young Leaders’s Fellowship Fund, and grant 2001/0036-V2002 186 from The Swedish Foundation for Health Care Sciences and Allergy Research. The author wishes to thank the two reviewers for their constructive comments.

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