The Relationship Between Trauma Exposure and Nonclinical Psychosis: A Systematic Review and Meta-Analysis.

Abstract

Background: Trauma exposure is linked to increased psychosis risk; however, critical questions remain about how trauma exposure relates to psychotic-like experiences (PLEs), including the overall effect and whether trauma type, number of exposures, and methodological/sample characteristics influence the relationship.

Method: A meta-analysis (following PRISMA guidelines) on the relationship between childhood trauma and PLEs was conducted. Effect size by trauma type (emotional abuse, physical abuse, sexual abuse, emotional neglect, physical neglect, bullying, discrimination) and number, assessment methods for trauma and PLEs, and the sex and race/ethnicity compositions of the sample were recorded.

Results: 92 studies (104 samples; 171,828 individuals) were included. The mean effect size was r=.23 and there was some evidence of publication bias, z=2.039, p=.04. A fail-safe n calculation indicated that 7,881 analyses with null results would need to be added for the effect to be non-significant (p≥.05). Effect sizes by trauma type ranged from r=.16 (sexual abuse) to r=.26 (emotional abuse). Bullying had an effect size of r=.28 and discrimination had an effect size of r=.23. Notably, effect size increased as number of trauma exposures increased.

Discussion: This meta-analysis highlights the importance of expanding the assessment of trauma, including information about chronicity and about exposures such as bullying and discrimination. Research examining the relationship of these more nuanced measures of trauma exposure and later psychosis risk is critical to inform public health and policy decisions.