Objectives: To explore the psychometric properties of 3 widely used measures of depression in a sample of individuals with traumatic brain injury (TBI) and major depressive disorder and refine them to maximize efficiency.
Design: Secondary analysis of data from a randomized controlled trial of cognitive-behavioral therapy for depression after TBI.
Setting: Nationwide recruitment from community and clinical settings.
Participants: One hundred adults within 10 years of complicated mild to severe TBI.
Intervention: Telephone and in-person cognitive-behavioral therapy.
Main measures: Patient Health Questionnaire-9 (PHQ-9), Symptom Checklist-20, and Hamilton Depression Rating Scale.
Results: We used Rasch rating scale analysis and multilevel modeling to investigate the 3 measures. Measurement properties of each of the depression measures were strong. We explored modifications to the rating scales to improve efficiency while retaining strong psychometric characteristics. Correlations among these revised measures were high. Treatment effects of each revised depression measure were compared using a multilevel model, and effect size estimates were comparable among the revised PHQ-9, Symptom Checklist-20, and Hamilton Depression Rating Scale.
Conclusions: Although each of the 3 measures demonstrated adequate reliability, the efficiency of all 3 instruments was improved with rating scale analysis. The PHQ-9 required the fewest modifications and functions well as a measure of depression among those with TBI.
Trial registration: ClinicalTrials.gov NCT00878150.