Abstract
BACKGROUND AND HYPOTHESIS: Psychotic and traumatic-stress symptoms commonly co-occur. Psychological interventions have increasingly targeted these co-occurring symptoms. However, information on their efficacy, tolerability, and acceptability is limited in this evolving field. STUDY DESIGN: After preregistration at PROSPERO (CRD42024553934), we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) of psychological interventions with persons aged 16+ reporting both psychotic and traumatic-stress symptoms. PubMed, CINAHL, Embase, PsycINFO, Clinicaltrials.gov, and Web of Science were searched in July 2024. We used the Revised Cochrane Risk-of-Bias Tool for Randomized Trials (RoB-2) for bias assessment. Random-effects models were used to synthesize clinical outcomes, while meta-regression was applied when 10 effect sizes were reported per outcome. STUDY RESULTS: We included 10 RCTs with 559 participants. Interventions primarily targeted trauma-related symptoms and were seemingly tolerable and acceptable, with low adverse event profiles and a dropout rate of 14%. In comparison to usual treatments and active control treatments, interventions significantly decreased traumatic-stress symptoms at post-treatment (g = 0.33, 95% CI [0.08, 0.57]), with meta-regression favoring interventions primarily employing exposure (gdiff = 0.59, [0.22, 0.97]). Interventions significantly decreased traumatic-stress symptoms at follow-up (g = 0.34, [0.12, 0.56]), but not total psychotic, positive, or negative symptoms at either timeframe. CONCLUSIONS: Findings suggest that psychological interventions for co-occurring psychotic and traumatic-stress symptoms are safe, tolerable, and may reduce traumatic-stress symptoms when employing exposure. Considering the substantial risk of bias, the small number of trials, non-significant results for other clinical and functional outcomes, and unexplained heterogeneity, further research is needed.