Location-based differences in cognition and functional capacity: Consistent levels of impairment in participants with schizophrenia compared to healthy controls.

Cognitive performance manifests regional differences, correlated with education. There is less information available about regional differences in performance-based measures of functional capacity. In multi-national trials focused on cognitive enhancement, it may be impossible to validate every measure in all locations. It is unknown if regional differences in healthy controls' (HC) performance affects relative levels of impairment in participants with schizophrenia (SCZ). A multi-site study comparing SCZ and HC administered the MATRICS Consensus Cognitive Battery (MCCB) and Virtual Reality Functional Capacity Assessment Tool (VRFCAT) to 164 HC participants and 164 with SCZ across three sites (Columbia, SC, Miami, and San Diego) and a representative sample of HC (n = 390) completed the VRFCAT in Durham, NC. Performance was compared between HC and SCZ participants at the validation sites. There were statistically significant cross-site differences in HC performance on both the MCCB and VRFCAT. Differences between HC and SCZ on MCCB and VRFCAT were substantial at all three sites, indicating that regional variations in HC performance did not induce reduced differences from SCZ participants. Regional differences were smaller than diagnostic group differences, suggesting that relative impairments of participants with SCZ is consistently preserved across performance differences in HC.