A Confirmatory Factor Analytic Investigation of the TAS–20: Corroboration of a Five-Factor Model and Suggestions for Improvement

Abstract

Alexithymia represents an individual difference dimension characterized by difficulties identifying emotions, difficulties describing emotions, and a utilitarian approach to thinking. The Toronto Alexithymia Scale–20 (TAS–20; Bagby, Parker, & Taylor, 1994) is a frequently used inventory to measure alexithymia, and although several studies have examined the factor structure of the TAS–20, a number of issues remain unresolved. Specifically, the severely unbalanced item-keyed nature of the TAS–20 has been suggested to limit the interpretation of the substantive Externally Oriented Thinking (EOT) factor. Further, it has also been suggested that the EOT factor may be better represented by 2 oblique factors. A review of the TAS–20 confirmatory factory analysis (CFA) literature has suggested that some improvement in CFA strategies could possibly be afforded by using a nested factors modeling approach. Based on a sample of 355 participants, we demonstrated that the TAS–20 was better represented by a nested factors model with 5 substantive factors. A novel, latent variable approach to estimating internal consistency reliability revealed that the subscales within the TAS–20 were associated with unacceptably low levels of reliability independently of the global alexithymia factor. Although there was some CFA evidence to suggest the plausibility of a negatively keyed factor, a thorough examination of the items in question offered an alternative interpretation. Further development of the TAS–20′s Externally Oriented Thinking subscale is encouraged.