Comparative Effectiveness of Medication vs. CBT in Depressed Low-income Women
C Hendricks Brown, University of Miami 
Joyce Y. Chung, National Institute of Mental Health 
Jeanne Miranda, University of California Los Angeles 
*Juned Siddique, Northwestern University 

Keywords: growth mixture modeling, personalized medicine

Major depression, a disorder with early onset and often chronic course, imposes a high individual burden of pain, suffering, and disability. Most depression treatment studies include primarily White and middle-class populations so that little is known about the effectiveness of established treatments for ethnic minority and poor individuals. A frequent characteristic of depression studies is that outcomes over time are subject to considerable between-subject heterogeneity due to the fact that patients often follow different trajectories over time. When comparing the effectiveness of different treatments, it is important to identify and take into account these different trajectories because the effectiveness of an intervention may depend on the trajectory class of the participants. Growth mixture modeling (GMM) allows the analyst to estimate several different trajectories over the course of a study. In this way, GMM may do a better job of capturing between-subject variability because it does not require that all individuals follow the same trajectory over time. In this talk, we compare the effectiveness of medication versus cognitive behavioral therapy using data from the WECare study, a longitudinal depression treatment study of low-income mostly minority women with depression. Using GMM we identify and predict response trajectories over the course of the study then compare the effectiveness of antidepressant medication and cognitive behavioral therapy within these trajectories. We also attempt to classify subjects in the various response trajectories in terms of their baseline characteristics including socioeconomic and clinical features to identify which patients are more likely to benefit from a given intervention.