Modifiable predictors of self-reported and performance-based functioning in individuals with schizophrenia-spectrum disorders and high levels of negative symptoms

Individuals with schizophrenia who have high negative symptoms are at high risk for poor functional outcomes. However, the determinants of psychosocial functioning in this group are not well understood. We aimed to examine modifiable predictors of both objective, performance-based functional capacity and social skills, and self-reported functioning in individuals with schizophrenia and schizoaffective disorder and high negative symptoms. Fifty-five adults with moderate-to-severe negative symptoms were administered measures of neuropsychological performance, performance-based functional capacity and social competence, self-reported functioning, psychiatric symptom severity, defeatist/asocial beliefs, and intrinsic motivation. In the context of multiple significant predictor variables identified through bivariate correlations, multiple regression models showed that neuropsychological performance was the only significant predictor of performance-based functional capacity; neuropsychological performance and motivation/pleasure negative symptoms were significant predictors of performance-based social competence. For two different measures of self-reported functioning, intrinsic motivation, asocial beliefs, and diminished expression emerged as significant predictors. Neurocognitive ability was a better predictor of performance-based functional skills whereas motivation and beliefs more strongly predicted self-reported real-world functioning. The findings of this study suggest a complex picture of predictors of performance-based functional capacity (objective neuropsychological functioning) and self-reported functioning (motivation and beliefs), underscoring the clinical and scientific utility of including both self-reported and objective measures of functioning to identify treatment approach. Individuals with high negative symptoms and a cognitive/functional skills deficit may benefit from interventions such as cognitive remediation or skills training, whereas individuals with motivational difficulties may benefit from treatments such as cognitive behavioral therapy.