The Relations of Cognitive, Behavioral, and Physical Activity Variables to Depression Severity in Traumatic Brain Injury: Reanalysis of Data From a Randomized Controlled Trial.

The sample was relatively small: 100 people were randomized and outcome data were obtained on 88 at 16 weeks. Participants were mostly male (63%), non-Hispanic White (90%) and middle-aged (mean 45.8 years), so the results may not generalize to the broader population of people with TBI and depression. The study had no non-depressed TBI control group and compared participants with existing norms, so differences could reflect TBI or other sample characteristics rather than depression alone. The reanalysis combined treatment and control groups, so it cannot show that a treatment changed the cognitive, behavioral or physical activity variables. The paper lacks information on what size change on the negative thoughts, dysfunctional attitudes or environmental rewards measures is clinically meaningful. The original CBT did not improve environmental rewards or negative automatic thoughts more than usual care, and the trial did not explicitly focus on improving physical activity.

The authors reported no financial or other relationships with any organization that might have an interest in or influence upon the work. The article is listed as supported by NIH extramural research funding.

Do not conclude that CBT or behavioral activation is better than usual care. The original trial showed similar improvement, and this reanalysis combined groups, so the environmental-reward finding is an association, not proof of treatment effect.