Reliability and validity of the Toronto Structured Interview for Alexithymia in a mixed clinical and nonclinical sample from Italy

The reliability and validity of the Toronto Structured Interview for Alexithymia (TSIA) have been demonstrated in previous studies with English-speaking community and psychiatric samples and a German-speaking psychiatric sample. The aim of this study was to evaluate the psychometric properties of the TSIA in a mixed clinical and nonclinical sample from Italy. The original English version of the TSIA was translated into Italian and administered, along with the 20-item Toronto Alexithymia Scale (TAS-20), to 80 healthy subjects, 69 medical outpatients, and 62 psychiatric outpatients. Eighty-one videotaped interviews were used for assessing the interrater reliability. Confirmatory factor analysis supported the hierarchical, four-factor structure of the TSIA obtained in previous studies, with four lower-order factors nested within two higher-order latent factors. The TSIA also demonstrated internal and interrater reliability, and concurrent validity with the TAS-20. The results support the use of the TSIA to assess alexithymia especially when a multimethod approach to measurement is possible.     

Cross-cultural alexithymia: validity of the 20-item Toronto Alexithymia Scale in North American aboriginal populations

OBJECTIVE: The generalizability of the alexithymia construct to North American aboriginal culture was examined by assessing the replicability of the factor structure of the 20-item Toronto Alexithymia Scale (TAS-20) in two different adult samples. The study also assessed the reliability of the scale and the influence of gender, age, and education on alexithymia levels. METHOD: The first sample was a community-based group of 123 aboriginal men and women; the second sample was 102 male aboriginal offenders. Both samples completed the TAS-20. RESULTS: The replicability of the three-factor structure for the TAS-20 was supported in both groups using confirmatory factor analysis (CFA). The TAS-20 and its three factors demonstrated adequate internal reliability, and the variables of gender, age, and education accounted for small or nonsignificant amounts of variability in total TAS-20 and factor scale scores. CONCLUSION: The results provide additional support for the factorial validity of the TAS-20 in diverse cultural groups.     

The assessment of alexithymia: A critical review of the literature and a psychometric study of the Toronto Alexithymia Scale-20

Objective: The objectives were to give an overview of studies on the validity of the Toronto Alexithymia Scale (TAS-20) and to present data regarding the validity of the TAS-20. Methods: The literature on the psychometric properties of the TAS-20 was reviewed and a study was conducted of its psychometric properties in a sample of students and a sample of psychiatric outpatients using a statistical method allowing identification of a stable factor structure. Results: The review revealed that the majority of studies on the TAS-20 were conducted with nonpatient samples. The factorial validity and reliability of the dimensions ‘identifying feelings’ (DIF) and ‘describing feelings’ (DDF) could be replicated in many of these studies. However, in practically all studies the dimension ‘externally oriented thinking’ (EOT) appears to be unreliable. In addition, the presupposed fantasy aspect of the alexithymia construct is not included in the TAS-20. Although many studies were conducted on the construct validity of the TAS-20, no studies have been published on its criterion validity. Some studies show a different factor structure to exist in patient samples. This was confirmed in our own study in which the dimensions ‘identifying feelings’ and ‘describing feelings’ collapsed into one single subscale. As in other studies, the reliability of the dimension ‘EOT’ was low. Conclusion: The TAS-20 has some important shortcomings with respect to validity and reliability. For the assessment of alexithymia in empirical research, it is recommended to use the TAS-20 in combination with other instruments. We do not recommend the TAS-20 to be used in clinical practice.     

The assessment of alexithymia: a critical review of the literature and a psychometric study of the Toronto Alexithymia Scale-20

Objective: The objectives were to give an overview of studies on the validity of the Toronto Alexithymia Scale (TAS-20) and to present data regarding the validity of the TAS-20. Methods: The literature on the psychometric properties of the TAS-20 was reviewed and a study was conducted of its psychometric properties in a sample of students and a sample of psychiatric outpatients using a statistical method allowing identification of a stable factor structure. Results: The review revealed that the majority of studies on the TAS-20 were conducted with nonpatient samples. The factorial validity and reliability of the dimensions ‘identifying feelings’ (DIF) and ‘describing feelings’ (DDF) could be replicated in many of these studies. However, in practically all studies the dimension ‘externally oriented thinking’ (EOT) appears to be unreliable. In addition, the presupposed fantasy aspect of the alexithymia construct is not included in the TAS-20. Although many studies were conducted on the construct validity of the TAS-20, no studies have been published on its criterion validity. Some studies show a different factor structure to exist in patient samples. This was confirmed in our own study in which the dimensions ‘identifying feelings’ and ‘describing feelings’ collapsed into one single subscale. As in other studies, the reliability of the dimension ‘EOT’ was low. Conclusion: The TAS-20 has some important shortcomings with respect to validity and reliability. For the assessment of alexithymia in empirical research, it is recommended to use the TAS-20 in combination with other instruments. We do not recommend the TAS-20 to be used in clinical practice.     

The 20-Item Toronto Alexithymia Scale. III. Reliability and factorial validity in a community population

OBJECTIVE: Some researchers have questioned the stability of the three-factor structure of the 20-Item Toronto Alexithymia Scale (TAS-20) or the reliability of one or more factors of the scale. The aim of this study was to assess the replicability of the factor structure of the TAS-20 in a large community sample and to determine also whether the same three-factor structure can be recovered in men and women. The study also assessed the reliability of the scale and the influence of gender, age, and education on TAS-20 scores. METHOD: The TAS-20 was administered to 1933 adults (880 men and 1053 women) residing in several small cities and towns in Ontario, Canada. The factor structure of the scale was assessed using confirmatory factor analysis (CFA). RESULTS: The three-factor structure of the TAS-20 was replicable in the entire community sample and also separately in men and women. The TAS-20 and its three factors demonstrated internal reliability, and the variables of gender, age, and education accounted for relatively small or modest amounts of variability in total TAS-20 and factor scale scores. CONCLUSION: The results provide strong support for the reliability and factorial validity of the TAS-20 and indicate the importance of using CFA when assessing the replicability and theoretical integrity of the factor structure of the scale.     

The 20-Item Toronto Alexithymia Scale. IV. Reliability and factorial validity in different languages and cultures

OBJECTIVE: The aim of this paper was to review findings from studies that have evaluated the reliability and factorial validity of the 20-item Toronto Alexithymia Scale (TAS-20) in different languages and cultures. METHOD: Data from published articles as well as unpublished data from various countries were reviewed to determine whether the three-factor structure of the TAS-20 is replicable in different cultures by the method of confirmatory factor analysis (CFA), and whether the scale and its three-factor scales show internal reliability in these cultures. RESULTS: The TAS-20 has been translated adequately into 18 different languages and evaluated by CFA in 19 different countries. There is strong support for the generalizability of the three-factor structure of the scale across languages and cultures. In addition, the full-scale TAS-20 and the first two factors show adequate to good internal reliability for most of the translations. In most cultures where English is not the primary language, however, the third factor lacks internal reliability; this might be due to cultural differences or a response bias to the several negatively keyed items on this factor. CONCLUSION: The findings support the use of the TAS-20 in cross-cultural research, and suggest that alexithymia may be a universal trait that transcends cultural differences.     

Psychometric properties of the Finnish 20-item Toronto Alexithymia Scale

The aim of this study was to examine the factor structure and the validity of the Finnish version of the 20-item Toronto Alexithymia Scale (TAS-20). As part of the Northern Finland 1966 Birth Cohort Project, the TAS-20 was presented to a sample of 5034 31-year old persons. A confirmatory factor analysis showed that the three-factor model, earlier established with the original TAS-20, was in agreement with the Finnish version of the scale. Three criteria of goodness-of-fit met the standards for adequacy of fit. For the total scale, internal reliability (Cronbach's alpha) was 0.83 and for the three subscales (factors 1, 2, and 3) it was 0.81, 0.77, and 0.66, respectively. Two- and one-factor models for TAS-20 were also examined, but the other models did not perform as well as the three-factor model. The factor model also worked well with a sample of 516 students with a mean age of 24.8 years. In conclusion, the TAS-20 scale is useful in the Finnish version, too.     

Cross-cultural validation of a Chinese translation of the 20-item Toronto Alexithymia Scale

BACKGROUND: The purpose of the present study was to develop a Chinese translation of the 20-item Toronto Alexithymia Scale (TAS-20-C) and examine its reliability and factorial validity. METHODS: The original English version of the TAS-20 was first translated into Chinese and then backtranslated and modified until cross-language equivalence was established. This version was then completed by 870 undergraduate students and 179 clinical patients in China. Internal reliability, retest reliability, and factorial validity were evaluated. RESULTS: The TAS-20-C showed adequate internal and retest reliability in both samples. Average TAS-20-C scores in Chinese samples were slightly higher than, but comparable to, TAS-20 scores in English-speaking Canadian samples; as well, scores were higher in the clinical sample than in the student sample. Finally, confirmatory factor analysis supported the 3-factor structure of the TAS-20 in both samples. CONCLUSIONS: The TAS-20-C is a promising instrument for reliable and valid measurement of alexithymia in China.     

Reliability and Validity of the 20-Item Toronto Alexithymia Scale in Korean Adolescents

Objective

Adolescence is a period of developing emotional regulation. However, alexithymia has rarely been examined during this period. The objective of this study is to examine the factor structure and internal consistency of the Korean version of the 20-item Toronto Alexithymia Scale (TAS-20K) in normal adolescents in South Korea.

Methods

The TAS-20K was administered to a sample of 290 adolescents aged from 12 to 16 years old. Internal reliability, test-retest reliability, and factorial validity were evaluated.

Results

The three factors of the TAS-20K were confirmed by confirmatory factor analysis. The internal consistency, measured using Cronbach''s alpha coefficient was acceptable for difficulty in identifying feelings, good for difficulty in describing feelings, and acceptable for externally oriented thinking.

Conclusion

Our study indicates that the TAS-20K is an appropriate instrument to assess alexithymia in Korean adolescents.     

Psychometric properties of the Toronto Alexithymia Scale (TAS-20) for substance users

OBJECTIVE: To determine the psychometric properties of the Toronto Alexithymia Scale (TAS-20), an established self-report measure of alexithymia, for a substance user sample participating in a clinical trial of outpatient cognitive-behavioral therapies (N=230). METHODS: Confirmatory and exploratory factor analyses were used to determine the number and nature of the factors underlying the TAS-20 in a sample of substance users. Structural equation modeling was used to determine the predictive validity of the TAS-20. RESULTS: A factor structure comparable, but not identical, with TAS-20 psychometric results with other populations was found; alpha coefficients were .88 for the feelings factor, .62 for the external thinking factor, and .87 for the total score. Although, on average, the substance users did not appear to have elevated alexithymia scores compared with the undergraduate students, alexithymia predicted less treatment engagement, i.e., fewer sessions attended and weaker helping alliance. Alexithymia also predicted alcohol use outcomes but not drug use outcomes. The relation between alexithymia and drinking outcome was conditional on whether the patient was using solely alcohol at baseline. CONCLUSION: The TAS-20 has reasonably good psychometric properties in this sample, which might be improved by dropping several marginal questionnaire items. Alexithymia appears to attenuate substance abuse treatment engagement. More clinical and research experience with this construct and specific instrument in substance user samples is needed.     

Observer- and self-rated alexithymia in eating disorder patients: levels and correspondence among three measures

OBJECTIVES: Our objectives were to evaluate the psychometric properties of the Observer Alexithymia Scale (OAS) in eating disorder patients, alexithymia severity across diagnostic subgroups, and correspondence among three alexithymia measures. METHOD: Seventy-five women, each with an eating disorder diagnosis, completed two alexithymia self-reports, the 20-item Toronto Alexithymia Scale (TAS-20) and the Bermond-Vorst Alexithymia Questionnaire-version B (BVAQ-B), and asked a relative or an acquaintance to rate them using the OAS. RESULTS: The OAS showed acceptable discriminant validity and interrater reliability. Patients' OAS scores were higher than scores reported for people-in-general samples and lower than those for outpatient clinical samples. No statistically significant OAS, TAS-20, and BVAQ-B score differences were found between the patients with anorexia nervosa restrictive type and those with bulimia nervosa. OAS, TAS-20, and BVAQ-B total scores were moderately, positively, and significantly correlated. CONCLUSION: These clinical data show the psychometric strength of the OAS, which reasonably can be recommended for use with the TAS-20 in research and clinical practice.     

Alexithymia in patients with psoriasis: clinical correlates and psychometric properties of the Toronto Alexithymia Scale-20

OBJECTIVE: The objective of this study was to examine the psychometric properties and clinical correlates of the 20-item Toronto Alexithymia Scale (TAS-20) in patients with psoriasis. METHODS: Three hundred patients with psoriasis completed the TAS-20 and had the severity of their psoriasis clinically assessed. Test-retest reliability was assessed over 10 weeks in a subset of 71 patients receiving standard medical treatment for their psoriasis. Examination of the factor structure employed both exploratory (EFA) and confirmatory (CFA) factor analysis techniques. RESULTS: The overall prevalence of alexithymia in this population of psoriasis patients, as indicated by the TAS-20, was 33%. The TAS-20 total score was not related to clinical severity, age, age at onset or duration of psoriasis. The 10-week test-retest reliability on a sample of 71 psoriasis patients, pre- and posttreatment with photochemotherapy, was found to be acceptable (r=.69; P<.001). EFA produced no stable solutions. The three-factor structure of the TAS-20 using CFA was also not replicable in this sample. CONCLUSIONS: The findings of this study support the contention that alexithymia is not significantly influenced by either disease severity or chronicity in patients with psoriasis. It is recommended that when employing the TAS-20 in patients with psoriasis, caution is exercised in the interpretation of the scale scores and that further psychometric evaluation of the scale is undertaken as appropriate.     

An investigation of the construct validity of the 20-Item Toronto Alexithymia Scale through the use of a verbalization task

OBJECTIVE: The construct validity of the 20-Item Toronto Alexithymia Scale (TAS-20) was examined through a verbalization task requiring participants to discuss a past distressing event. METHODS: Verbalizations were transcribed and coded for the frequency and number of different negative and positive emotion words used. Relationships between the TAS-20 and these variables were examined. RESULTS: Controlling for negative affect (NA), the difficulty identifying feelings (DIF) subscale was positively associated with the frequency of negative emotion words used and negatively associated with the frequency and number of different positive emotion words used during the verbalization task. High, compared with low, scoring TAS-20 participants used a lower frequency of and fewer different positive emotion words. CONCLUSION: The TAS-20 may be measuring negative emotional expressivity separate from negative affectivity, as well as a reduced capacity to access and elaborate upon positive emotion. Findings are discussed in regard to improving the conceptualization and measurement of emotional deficits in alexithymia.     

Is there a reliable factorial structure in the 20-item Toronto Alexithymia Scale? A comparison of factor models in clinical and normal adult samples

OBJECTIVES: The 20-item Toronto Alexithymia Scale (TAS-20) is the most widely used instrument for measuring alexithymia. However, different studies did not always yield identical factor structures of this scale. The present study aims at clarifying some discrepant results. METHODS: Maximum likelihood confirmatory factor analyses of a German version of the TAS-20 were conducted on data from a clinical sample (N=204) and a sample of normal adults (N=224). Five different models with one to four factors were compared. RESULTS: A four-factor model with factors (F1) "Difficulty identifying feelings" (F2), "Difficulty describing feelings" (F3), "Low importance of emotion" and (F4) "Pragmatic thinking" and a three-factor model with the combined factor "Difficulties in identifying and describing feelings" described the data best. Factors related to "externally oriented thinking" provided no acceptable level of reliability. CONCLUSIONS: Results from the present and other studies indicate that the factorial structure of the TAS-20 may vary across samples. Whether factor structures different from the common three-factor structure are an exception in some mainly clinical populations or a common phenomenon outside student populations has still to be determined. For a further exploration of the factor structure of the TAS-20 in different populations, it would be important not only to test the fit of the common three-factor model, but also to consider other competing solutions like the models of the present study.     

Ethnolinguistic correlates of alexithymia: Toward a cultural perspective

Gender and ethnolinguistic correlates of alexithymia were explored by having a large, ethnically heterogeneous sample of university students in Toronto, Canada, complete the 20-item Toronto Alexithymia Scale (TAS-20). Men scored higher in the externally oriented thinking factor than women. Non-native English speakers scored higher on the overall TAS-20, as well as on the difficulty identifying feelings factor, than native English speakers. Further analyses showed that native Chinese language speakers scored consistently higher than native English and native European language speakers on the overall TAS-20 and its three underlying factors. These ethnolinguistic differences may reflect sociocultural influences making ethnic Chinese individuals likely to be less psychologically minded and more somatically oriented vis-à-vis their emotions than those from Western, ethnocultural traditions. Whether alexithymia should be construed as an “etic” construct (i.e., widely applicable across many different cultures) or an “emic” one (i.e., applicable to only one or two cultures) is discussed.     

The 20-item Toronto alexithymia scale: structural validity, internal consistency and prevalence of alexithymia in a Swiss adolescent sample

BACKGROUND: The alexithymia construct is mainly characterized by a difficulty in identifying and expressing feelings that is thought to reflect a deficit in cognitive processing and regulation of emotional states. During the last decade, alexithymia has been associated with a large variety of medical and psychiatric disorders in the adult population. Although adolescence is probably an opportune time to explore processes of emotion regulation, alexithymia has been rarely examined during this period. The 20-item Toronto alexithymia scale (TAS-20) is the most widely used self-report measure of alexithymia. For this scale, a three-factor structure was proposed: difficulty identifying feelings (DIF), difficulty describing feelings (DDF) and externally oriented thinking (EOT). Research has yielded considerable evidence that the TAS-20 is a reliable and valid measure of alexithymia in normal and clinical adult samples. To date, no psychometric data concerning the use of the TAS-20 with adolescent samples are available. OBJECTIVES: The aim of the study is to provide psychometric data concerning the TAS-20 when administered to healthy adolescents. Furthermore, in a developmental perspective, this study explores the evolution of alexithymia across age groups in adolescence. METHOD: The TAS-20 was administered to a sample of 264 adolescents aged from 14 to 19 years. In order to compare alexithymia across age groups, the sample was divided into three groups: group 1 (<16 years old), group 2 (16-17 years old) and group 3 (>17 years old). RESULTS: Results of a confirmatory factor analysis (CFA) confirmed that the data fitted well to the three-factor model of the TAS-20 (chi(2)/df=2.22, GFI=0.88, AGFI=0.84 and RMSEA=0.068). The internal reliability coefficients and mean interitem correlations are acceptable for DIF (alpha>0.60; mean interitem correlation=0.22) and good for DDF (alpha>0.70, mean interitem correlation=0.33). As often reported in most translations of the TAS-20, the internal reliability of EOT is poor. Results of a one-way Anova showed a significant linear trend indicating that, with age, the level of alexithymia (TAS-20 total score), the difficulty in identifying feelings and the externally oriented thinking decreased. DISCUSSION: This study demonstrated that the TAS-20 has sufficient construct validity in a non-clinical sample of adolescents. Our results support the idea that adolescence period is associated with the development of the ability to regulate emotions.     

Assessing the reliability and validity of the Bermond-Vorst Alexithymia Questionnaire among U.S. Anglo and U.S. Hispanic samples

OBJECTIVE: The aim of this paper is to assess the psychometric properties of the Bermond-Vorst Alexithymia Questionnaire (BVAQ) in U.S. Anglo and U.S. Hispanic samples of college students. METHOD: One hundred ninety-four U.S. Hispanics and 304 U.S. Anglos participated in the study. In addition to completing the BVAQ, participants completed the 20-item Toronto Alexithymia Scale (TAS-20), the Beck Depression Inventory (BDI), and the Eysenck Neuroticism Scale (ENS). RESULTS: BVAQ and TAS-20 subscales were correlated across groups. While the identifying and verbalizing composites of the BVAQ subscales were predictive of neuroticism and depression across groups in the expected direction, the fantasizing subscale of the BVAQ was negatively predictive of depression and neuroticism across groups. CONCLUSION: Given the unexpected findings associated with some of the BVAQ subscales, future research should explore the dimensionality of alexithymia.     

Relationships between alexithymia and psychological characteristics associated with eating disorders

This study examines the relationships between alexithymia and psychological characteristics and behaviors that are commonly associated with eating disorders. The 20-item Toronto Alexithymia Scale (TAS-20) and the Eating Disorder Inventory (EDI) were administered to a group of 48 female patients with anorexia nervosa, a matched comparison group of 30 normal women, and an unmatched comparison group of 116 male and 118 female university students. In the anorexic and male student groups, the TAS-20 correlated significantly and positively with the EDI subscales, Ineffectiveness, Interpersonal Distrust, Interoceptive Awareness, and Maturity Fears. The TAS-20 correlated significantly only with Interpersonal Distrust in the matched comparison group, and only with Ineffectiveness and Interpersonal Distrust in the female student group. The results suggest that alexithymia is related to several psychological traits that are characteristic of patients with eating disorders and thought to play a role in the development of the disorders, but is unrelated to attitudes and behaviors concerning abnormal eating and body weight and shape.     

Alexithymia in parents of daughters with eating disorders: its relationships with psychopathological and personality variables

OBJECTIVES: The purpose of this research was to investigate alexithymia among parents of a daughter with eating disorders (EDs) and to relate alexithymia to personality and psychopathology characteristics. METHODS: Parents of 73 women with ED (20 with anorexia nervosa, restrictive subtype (ANR), 23 with anorexia nervosa, bulimic subtype (ANB) and 30 with bulimia nervosa (BN)) and parents of 72 normal women were evaluated with the Toronto Alexithymia Scale (TAS-20), the Eysenck Personality Questionnaire, the Beck Depression Inventory and the Self-Rating Anxiety Scale. RESULTS: The parents of daughters with ED show higher scores in the TAS-20 and its factors than the controls. TAS-20 scores of parents are associated with neuroticism, anxiety and depression. CONCLUSIONS: Alexithymia in parents of daughters with an ED could be a trait of personality, but it could also be a state due to distress. Alexithymia should be taken into account in order to help these parents express emotions.     

Temporal stability and differential relationships with neuroticism and extraversion of the three subscales of the 20-item Toronto Alexithymia Scale in clinical and nonclinical samples

OBJECTIVES: To examine the cross-sample and temporal stability of the three subscales of the 20-item Toronto Alexithymia Scale (TAS-20) and to study the pattern of associations between the TAS-20 scales, neuroticism, and alexithymia. METHODS: Two clinical and three nonclinical samples were included in the cross-sectional part of the study. One clinical and one nonclinical sample also participated in the 6-month follow-up study. To test the replicability of the three-factor structure of the TAS-20 across samples, a principal component analysis was conducted, followed by a Procrustes rotation. Linear regression analyses were conducted to examine temporal stability and to determine the specificity of the associations among the TAS-20 scales, neuroticism, and extraversion. RESULTS: The three-factor structure of the TAS-20 was confirmed across all five samples. With a few exceptions, neuroticism and extraversion attained a higher level of temporal stability than the alexithymia scales. The TAS-subscale measuring difficulty identifying feelings (DIF) was less stable in the clinical than in the nonclinical sample. Neuroticism was most strongly associated with DIF, whereas extraversion was mainly related to externally oriented thinking (EOT). A combination of both neuroticism and extraversion was the best predictor of difficulty describing feelings (DDF). CONCLUSIONS: Future studies on the psychometric properties and the clinical value of the TAS-20 should pay more attention to its subscales. Especially the EOT facet needs further examination.