Childhood Maltreatment and Psychosis: A Comparative Validity Study of Maltreatment Indices.

Childhood maltreatment is a robust risk factor for psychosis, but it remains unclear whether different measurement methods provide equivalent validity in predicting psychotic symptoms. This study compared the predictive validity of two common indices of maltreatment at age 12-children's self-report and Child Protective Services (CPS) reports-on the development of psychotic symptoms at age 18 using data from a large, multisite longitudinal study (N = 629). Consistent with prior research, agreement was low between indices, with the prevalence of self-reported maltreatment being 2-3 times higher. A quarter of the sample endorsed at least one psychotic symptom at age 18, most commonly delusions. While CPS-indicated maltreatment was generally not associated with later psychotic symptoms, all forms of self-reported maltreatment were. Sexual abuse demonstrated a particularly strong relationship with psychosis, especially hallucinations. These results suggest that self-reports may provide stronger predictive validity than CPS indications of maltreatment in the assessment of psychosis risk, indicating that a child's interpretation of trauma matters more than the traumatic event itself in this regard.