Individuals and families respond differently to different interventions, in different ways, at different times after injury. Premorbid functioning, personality, social support, and environmental demands are but a few of the factors that can profoundly influence outcome. In this variable response to treatment, cognitive rehabilitation is no different from treatment for cancer, diabetes, heart disease, Parkinson's disease, spinal cord injury, psychiatric disorders, or any other injury or disease process for which variable response to different treatments is the norm.

In our report, we carried out several meta-analyses using data from 18 randomized controlled trials. Based on data from these studies, we were able to conclude the following:
* Adults with moderate to severe traumatic brain injury who receive social skills training perform significantly better on measures of social communication than patients who receive no treatment.
* Adults with traumatic brain injury who receive comprehensive cognitive rehabilitation therapy report significant improvement on measures of quality of life compared to patients who receive a less intense form of therapy.
The strength of the evidence supporting our conclusions was low due to the small number of studies that addressed the outcomes of interest. Further, the evidence was too weak to draw any definitive conclusions about the effectiveness of cognitive rehabilitation therapy for treating deficits related to the following cognitive areas: attention, memory, visuospacial skills, and executive function. The following factors contributed to the weakness of the evidence: differences in the outcomes assessed in the studies, differences in the types of cognitive rehabilitation therapy methods/strategies employed across studies, differences in the control conditions, and/or insufficient number of studies addressing an outcome.