Discriminative capacities of the Toronto Structured Interview for Alexithymia in different clinical situations

Evaluation of alexithymia through self-report measures meets the difficulty of being dependent on the subject's capacity to report what (s)he feels and this very capacity is supposed to be deficient in alexithymics. Results may also be distorted by social desirability issues and defensive manouvers. Bagby et al. (2006) introduced the Toronto Structured Interview for Alexithymia (TSIA), where scores are not attributed by the subject but by the interviewer, on the basis of pertinent life examples. The original scale showed good psychometric properties. The Italian version (Caretti et al., 2011) confirmed the original 4-factor structure: Difficulty Identifying Feelings; Difficulty Describing Feelings; Externally Oriented Thinking; Imaginal Processes (the first three of which overlap with the corresponding factors of the TAS-20). The Italian version of the TSIA also demonstrated good internal and interrater reliability, and concurrent validity with the TAS-20. In order to begin testing the different discriminative capacities of the two instrument the TSIA and the TAS-20 were administered to different groups: general population; hypertensives; parents of children with emotional problems; subjects with common emotional disorders; subjects with eating disorders. It appears plausible that some of these groups may have difficulties in recognizing their deficit (somatic patients) or motives for denying them (parents). As expected, while the TAS-20 found differences with the general population only in Common Emotional Problems and in Eating Disorders, where subjects are clearly aware of some difficulty, the TSIA found high scores - in fact, the highest among groups - also in Hypertensives and in Parents. The TSIA appeared therefore capable to uncover deficits which were not apparent with the TAS-20.