Potential Mechanisms of Change in Virtual Reality-based Cognitive Behavioural Therapy and Standard Cognitive Behavioural Therapy for Schizophrenia-Related Paranoia: A Mediation Analysis from the FaceYourFears Trial.

BACKGROUND AND HYPOTHESIS: Cognitive models conceptualize paranoia in schizophrenia spectrum disorders as driven and maintained by mechanisms, which can be targeted by cognitive behavioral therapy for paranoia (CBTp). This study examined potential mechanisms as mediators. Safety behaviors, belief inflexibility, and core beliefs about self and others were hypothesized to differentially mediate outcomes in virtual reality-based CBTp (VR-CBTp) and CBTp, with safety behaviors expected to be more influential in VR-CBTp, and belief inflexibility and self-related core beliefs in CBTp.

STUDY

DESIGN

This secondary analysis of the FaceYourFears trial included a per-protocol sample with complete data (VR-CBTp: n = 96; CBTp: n = 90). Groups were comparable, except for greater in-session exposure in VR-CBTp. Pearson correlations, linear regression analyses and structural equation modeling (SEM), examined each mediator separately. Causal inferences could not be drawn.

STUDY

RESULTS

Pearson correlations of change scores showed that positive safety behaviors and negative self- and others-related core beliefs were associated with paranoia across both interventions. Regression analyses without covariate adjustment showed no significant between-group differences, except for belief inflexibility (P = .041), which became non-significant with covariate adjustment (age, sex, depression). SEM showed no differential mediation effects.

CONCLUSIONS

No mediators differed between interventions, and no hypotheses were supported. These results suggest similar mechanistic pathways in CBTp and VR-CBTp. Treatment selection may instead best be guided by factors such as symptom profile, patient preference, accessibility, and engagement. Findings are discussed in relation to prior mediation studies within the field, with implications for future research.