A longitudinal comparison of two neurocognitive test batteries in patients with schizophrenia and healthy volunteers: Time effects on neuropsychological performance and their relation to functional outcome

Abstract Cognitive impairment is a major unmet need in the treatment of schizophrenia. Over the last decade, the MATRICS Consensus Cognitive Battery (MCCB) has been used to assess the effects of novel treatments for cognitive impairment in schizophrenia. However, other cognitive-neuroscience-based cognitive batteries, such as the Cambridge Neuropsychological Test Automated Battery (CANTAB) have been suggested as an alternative to the MCCB. Although both batteries purport to assess cognitive function in psychosis, no previous study has attempted to examine their validity longitudinally and the potential overlap between the two batteries over time. The aim of the current study was to assess the relationship between the MCCB and the CANTAB in the longitudinal assessment of cognitive impairment in schizophrenia. A sample of 39 stable schizophrenia outpatients and 18 controls completed the MCCB and the CANTAB battery at baseline, and at 2, 4 and 8-weeks follow-up. Correlation analyses and a mixed-model repeated measures approach were used. We found no significant effect of time in the MCCB. In contrast, for the CANTAB a significant effect of time consistent with practice effects for the attention domain in the control group and for the visual learning, reasoning and problem-solving, and social cognition domains in patients, with subjects performing better at follow-up. In particular, a significant time ∗ battery interaction was found for those cognitive domains. These findings suggest there are specific differences across cognitive tests to assess cognitive impairments in schizophrenia and that measures derived from the CANTAB appear to be more prone to practice effects in these patients.