Longitudinal measurement invariance of the Patient Health Questionnaire-9 across racial/ethnic groups: Results from the traumatic brain injury model system study.

Based on these results, clinicians should feel confident using the PHQ-9 with diverse TBI patient populations, and researchers can reliably and validly employ it in TBI studies across racial/ethnic groups in the United States. Given the high rates of depression among individuals after TBI and its negative impact on their lives, this instrument will continue to be a key tool to measure the prognosis and success of rehabilitation programs. (PsycInfo Database Record (c) 2024 APA, all rights reserved).