Defeatist Performance Beliefs, Negative Symptoms, and Functional Outcome in Schizophrenia: A Meta-analytic Review.

Negative symptoms are a strong predictor of poor functional outcome in people with schizophrenia. Unfortunately there are few effective interventions for either negative symptoms or functional outcome, despite the identification of potential mechanisms. Recent research, however, has elucidated a new potential mechanism for negative symptoms and poor functional outcome: defeatist performance beliefs (DPB), or negative thoughts about one's ability to successfully perform goal-directed behavior that can prevent behavior initiation and engagement. We conducted 2 meta-analyses examining the relationship between DPB and both negative symptoms (n = 10 studies) and functional outcome (n = 8 studies) in people with schizophrenia. We found a small effect size for the relationship between DPB and negative symptoms, regardless of how negative symptoms were measured. We also found a small effect size for the relationship between DPB and functional outcome, which was significantly moderated by the method of assessing DPB and moderated by the sex composition of the study at a trend level. These findings highlight the potential of targeting DPB in psychosocial interventions for both negative symptoms and functional outcome.