Trust and psychosis: a systematic review and meta-analysis.

Background: Impaired trust in other humans is commonly seen in psychosis and it leads to poor societal functioning. However, examining trust behavior in an experimental setting is challenging. Investigators have used the trust game, a neuro-economic game to assess trust behavior in psychosis. However, the findings are inconsistent. Hence, we systematically reviewed the existing literature and conducted a meta-analysis to examine trust behavior in patients with psychosis, their relatives, and those at high risk for psychosis.

Methods: We searched electronic databases for studies that have examined trust game in patients with psychosis, published up to November 2021. The primary outcome measure was the baseline trust in a trust game by patients and controls. The meta-analysis was performed if at least three data sets of control and patient groups were available for that measure/design. We conducted meta-analyses with a random-effects model. The results were described narratively wherever meta-analysis was not possible due to paucity of studies.

Results: The searches across the databases including cross-references yielded 465 publications of which 10 studies were included in the final analysis. Baseline trust in the trust game was significantly lower in patients with psychosis compared to controls (SMD 0.39, 95% CI -0.14 to 0.64, -0.002). However, a similar decrease in baseline trust was not present in relatives of patients (SMD 0.08, 95% CI -0.20 to 0.36, -0.58).

Conclusions: The current meta-analysis suggests significant trust deficits in patients with psychosis. Future studies with a bigger sample size are required to understand the nature of trust deficits and factors affecting this impairment.