The performance of diagnostic measures of depression in alexithymic and nonalexithymic subjects

The objective of this study was to examine how the outcomes of a structured diagnostic interview for depression are related to the results of a self-report scale in alexithymic and nonalexithymic groups.

Subjects (N=389) recruited from primary care and psychiatric care completed the Depression Scale (DEPS) and the 20-item Toronto Alexithymia Scale. Major depression was diagnosed using the Composite International Diagnostic Interview-Short-Form by telephone.

In the group without major depression, the DEPS scores of the alexithymic subjects were significantly higher than those of the nonalexithymic subjects. In the group with major depression, the ideal cutoff points of the DEPS, assessed by receiver operating characteristic analyses, were essentially higher for the alexithymic patients.

Alexithymic subjects without major depression may be rated as depressive if the only criterion is the score on a self-report scale. Furthermore, alexithymic patients may require higher cutoff points in a self-report depression scale.