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

Abstract

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.