Is there a reliable factorial structure in the 20-item Toronto Alexithymia Scale? A comparison of factor models in clinical and normal adult samples Jochen Mu ¨ller*, Markus Bu ¨hner, Heiner Ellgring Institute for Psychology (I), University of Wu ¨rzburg, Marcusstr. 9–11, 97070 Wu ¨rzburg, Germany Received 26 March 2001; accepted 10 December 2002 Abstract Objective: 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. Method: Maximum likelihood con- firmatory 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. Conclusion: 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. D 2003 Elsevier Inc. All rights reserved. Keywords: Alexithymia; Measurement; Toronto Alexithymia Scale; Confirmatory factor analysis; Reliability Introduction The term ‘alexithymia’, coined by Sifneos [1,2], describes a set of affective and cognitive characteristics. They are believed to reflect deficits in the processing or regulation of emotions through mental processes [3]. As indicated by the Greek term, its most prominent feature is a marked difficulty in describing one’s own feelings to others. Alexithymia was defined as a multifacet construct composed of the following conceptually distinct, yet logically related, salient features: (a) ‘‘difficulty identifying feelings and distinguishing between feelings and the bodily sensations of emotional arousal’’, (b) ‘‘difficulty describing feelings to other peo- ple’’, (c) ‘‘constricted imaginal processes as evidenced by a paucity of fantasies’’ and (d) ‘‘a stimulus bound, externally orientated cognitive style’’ [3, p29]. Yet still, there is the problem of an adequate factorial structure of the construct in self-report measures. The Toronto Alexithymia Scale (TAS-26) [4] was intro- duced as a reliable and valid measure of the construct. After several revisions, the actual 20-item version (TAS-20) [5,6] resulted. For this scale, a three-factor structure was proposed [5]: (F1) ‘‘Difficulty identifying feelings’’, (F2) ‘‘Difficulty describing feelings’’ and (F3) ‘‘Externally oriented think- ing’’. Although the majority of the factor analytic studies about the TAS-20 seem to support the original three-factor solution, a closer review shows that there might be altern- ative factor structures. The results of studies using explor- atory factor analyses (EFAs) varied. In three studies, the common three-factor solution was preferred [5,7,8]. In one study, a one-factor model was found [9], and as had already 0022-3999/03/$ – see front matter D 2003 Elsevier Inc. All rights reserved. doi:10.1016/S0022-3999(03)00033-3 * Corresponding author. Tel.: +49-931-31-29-70/28-31; fax: +49- 931-888-70-59. E-mail address: j.mueller@psychologie.uni-wuerzburg.de (J. Mu ¨ller). Journal of Psychosomatic Research 55 (2003) 561 – 568