IDS-C and IDS-sr: psychometric properties in depressed in-patients

Area of Science:

• Psychiatry
• Clinical Psychology
• Psychometrics

Background:

• Depression assessment requires reliable and valid instruments.
• The Inventory for Depressive Symptomatology-Clinician (IDS-C) and Self-Rated (IDS-SR) are used to measure depressive symptom severity.
• Evaluating their psychometric properties in inpatient populations is crucial for clinical application.

Purpose of the Study:

• To assess the psychometric properties of IDS-C and IDS-SR in depressed inpatients.
• To compare the performance of IDS-C with the Montgomery and Asberg Depression Rating Scale (MADRS).
• To compare the performance of IDS-SR with the depression factor of the Symptom Check List (SCL-90R).

Main Methods:

• Sixty-eight depressed inpatients were assessed using IDS-C, IDS-SR, MADRS, and SCL-90R at multiple time points during antidepressant treatment.
• Psychometric properties evaluated included internal consistency (Cronbach's alpha) and concurrent validity.
• Sensitivity to change was assessed using paired t-tests and Principal Component Analyses (PCA) were conducted.

Main Results:

• Both IDS-C and IDS-SR demonstrated high internal consistency (Cronbach's alpha: 0.75 and 0.79, respectively).
• Concurrent validity was high: IDS-C with MADRS (r=0.81) and IDS-SR with SCL-90R (r=0.84).
• IDS-C showed potentially higher sensitivity to change than MADRS, while IDS-SR and SCL-90R showed similar sensitivity.

Conclusions:

• IDS-C and IDS-SR exhibit satisfactory psychometric properties in depressed inpatients, comparable to those in outpatients.
• The higher sensitivity to change of IDS-C may offer an advantage over MADRS in clinical trials.
• These findings support the utility of IDS-C and IDS-SR for assessing depression severity and treatment response.