THE INVENTORY OF DEPRESSIVE SYMPTOMATOLOGY (IDS) - PSYCHOMETRIC PROPERTIES

The psychometric properties of the 28- and 30-item versions of the Inv entory of Depressive Symptomatology, Clinician-Rated (IDS-C) and Self- Report (IDS-SR) are reported in a total of 434 (28-item) and 337 (30-i tem) adult out-patients with current major depressive disorder and 118 adult euthymic subjects (15 remitted depressed and 103 normal control s). Cronbach's alpha ranged from 0.92 to 0.94 for the total sample and from 0.76 to 0.82 for those with current depression. Item total corre lations, as well as several tests of concurrent and discriminant valid ity are reported. Factor analysis revealed three dimensions (cognitive /mood, anxiety/arousal and vegetative) for each scale. Analysis of sen sitivity to change in symptom severity in an open-label trial of fluox etine (N = 58) showed that the IDS-C and IDS-SR were highly related to the 17-item Hamilton Rating Scale for Depression. Given the more comp lete item coverage, satisfactory psychometric properties, and high cor relations with the above standard ratings, the 30-item IDS-C and IDS-S R can be used to evaluate depressive symptom severity. The availabilit y of similar item content for clinician-rated and self-reported versio ns allows more direct evaluations of these two perspectives.