Reviews and Overviews A Meta-Analysis of Cognitive Remediation in Schizophrenia

Objective: This study evaluated the effects of cognitive remediation for improving cognitive performance, symptoms, and psychosocial functioning in schizophrenia. Method: A meta-analysis was conducted of 26 randomized, controlled trials of cognitive remediation in schizophrenia including 1,151 patients. Results: Cognitive remediation was associated with significant improvements across all three outcomes, with a medium effect size for cognitive performance (0.41), a slightly lower effect size for psychosocial functioning (0.36), and a small effect size for symptoms (0.28). The effects of cognitive remediation on psychosocial functioning were significantly stronger in studies that provided adjunctive psychiatric rehabilitation than in those that provided cognitive remediation alone. Conclusions: Cognitive remediation produces moderate improvements in cognitive performance and, when combined with psychiatric rehabilitation, also improves functional outcomes. Cogni tive impairment is a core feature of schizophrenia, with converging evidence showing that it is strongly related to functioning in areas such as work, social relationships, and independent living (1, 2). Furthermore, cognitive functioning is a robust predictor of response to psychiatric rehabilitation (i.e., systematic efforts to improve the psychosocial functioning of persons with severe mental illness) (3), including outcomes such as work, social skills, and self-care (1, 4, 5). Because of the importance of cognitive impairment in schizophrenia, it has been identified as an appropriate target for interventions (6). Currently available pharmacological treatments have limited effects on cognition in schizophrenia In recent years, the number of studies that examined psychosocial functioning has grown sufficiently to permit a closer look at the impact of cognitive remediation. We conducted a meta-analysis of controlled studies to evaluate the effects of cognitive remediation on cognitive functioning, symptoms, and functional outcomes. We also examined whether characteristics of cognitive remediation programs (e.g., hours of cognitive training), the provision of adjunctive psychiatric rehabilitation, treatment settings, patient demographics, or type of control group was related to improved outcomes. We hypothesized that cognitive remediation would improve both cognitive functioning and psychosocial adjustment. We also hypothesized that programs that provided more hours of cognitive training would have stronger effects on cognitive functioning and that adjunctive psychiatric rehabilitation would be associated with greater improvements in functional outcomes. Method Studies for the meta-analysis were identified by conducting MEDLINE and PsycINFO searches for English language articles published in peer-reviewed journals. The following search terms were used: cognitive training, cognitive remediation, cognitive rehabilitation, and schizophrenia. Studies meeting the following criteria were included: 1) a randomized, controlled trial of a psychosocial intervention designed to improve cognitive functioning; 2) an assessment of performance with at least one neuropsychological measure that had the potential to reflect generalization of ef