From perception to functional outcome in schizophrenia: modeling the role of ability and motivation.

Abstract

CONTEXT Schizophrenia remains a highly disabling disorder, but the specific determinants and pathways that lead to functional impairment are not well understood. It is not known whether these key determinants of outcome lie on 1 or multiple pathways. OBJECTIVE To evaluate theoretically based models of pathways to functional outcome starting with early visual perception. The intervening variables were previously established determinants of outcome drawn from 2 general categories: ability (ie, social cognition and functional capacity) and beliefs/motivation (ie, defeatist beliefs, expressive and experiential negative symptoms). We evaluated an integrative model in which these intervening variables formed a single pathway to poor outcome. DESIGN This was a cross-sectional study that applied structural equation modeling to evaluate the relationships among determinants of functional outcome in schizophrenia. SETTING Assessments were conducted at a Veterans Administration Medical Center. PARTICIPANTS One hundred ninety-one clinically stable outpatients with schizophrenia or schizoaffective disorder were recruited from the community. RESULTS A measurement model showed that the latent variables of perception, social cognition, and functional outcome were well reflected by their indicators. An initial untrimmed structural model with functional capacity, defeatist beliefs, and expressive and experiential negative symptoms had good model fit. A final trimmed model was a single path running from perception to ability to motivational variables to outcome. It was more parsimonious and had better fit indices than the untrimmed model. Further, it could not be improved by adding or dropping connections that would change the single path to multiple paths. The indirect effect from perception to outcome was significant. CONCLUSIONS The final structural model was a single pathway running from perception to ability to beliefs/motivation to outcome. Hence, both ability and motivation appear to be needed for community functioning and can be modeled effectively on the same pathway.