Are apparent associations between parental representations and psychosis risk mediated by early trauma?

OBJECTIVE: It was investigated whether the reported association between representations of parental rearing style and psychosis does not represent a main effect, but instead is a proxy indicator of the true underlying risk factor of early trauma. METHOD: In a general population sample of 4045 individuals aged 18-64 years, first ever onset of positive psychotic symptoms at 3-year follow-up was assessed using the Composite International Diagnostic Interview and clinical interviews if indicated. Representations of parental rearing style were measured with the Parental Bonding Instrument (PBI). RESULTS: Lower baseline level of PBI parental care predicted onset of psychotic symptoms 2 years later. However, when trauma was included in the equation, a strong main effect of trauma emerged at the expense of the effect size of PBI low care. CONCLUSION: The results suggest that associations between representations of parental rearing style and psychosis may be an indicator of the effect of earlier exposure to childhood trauma.