The Inventory of Depressive Symptomatology (IDS): psychometric properties

TLDR

The Inventory of Depressive Symptomatology (IDS) clinician‑rated and self‑report versions were evaluated in 434 and 337 adult out‑patients with major depressive disorder and 118 euthymic controls, providing comparable item content for direct clinician‑ versus self‑report assessment. The study examined item total correlations and conducted concurrent and discriminant validity tests. The IDS‑C and IDS‑S R demonstrated high internal consistency (α 0.92–0.94 overall, 0.76–0.82 in depressed patients), identified three cognitive/mood, anxiety/arousal, and vegetative factors, showed strong sensitivity to fluoxetine‑induced symptom change, and correlated highly with the Hamilton Rating Scale, supporting the 30‑item versions for evaluating depressive severity.

Abstract

Synopsis The psychometric properties of the 28- and 30-item versions of the Inventory of Depressive Symptomatology, Clinician-Rated (IDS-C) and Self-Report (IDS-SR) are reported in a total of 434 (28-item) and 337 (30-item) adult out-patients with current major depressive disorder and 118 adult euthymic subjects (15 remitted depressed and 103 normal controls). Cronbach's α 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 correlations, as well as several tests of concurrent and discriminant validity are reported. Factor analysis revealed three dimensions (cognitive/mood, anxiety/arousal and vegetative) for each scale. Analysis of sensitivity to change in symptom severity in an open-label trial of fluoxetine ( 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 complete item coverage, satisfactory psychometric properties, and high correlations with the above standard ratings, the 30-item IDS-C and IDS-SR can be used to evaluate depressive symptom severity. The availability of similar item content for clinician-rated and self-reported versions allows more direct evaluations of these two perspectives.