Association between locus of control in childhood and psychotic symptoms in early adolescence: results from a large birth cohort.

INTRODUCTION. Specific attributional styles have been demonstrated in individuals with psychotic disorders and are implicated in the development of psychotic symptoms. We aimed to examine the association between locus of control (LOC) assessed in childhood and psychotic symptoms reported in early adolescence. METHODS. We used a prospective longitudinal design using data from a large birth cohort (the Avon Longitudinal Study of Parents and Children, ALPSAC). 6455 subjects completed a semistructured clinical interview assessing 12 individual psychotic symptoms at a mean age of 12.9 years. A measure of LOC was previously collected in the cohort at the age of 8. RESULTS. Children who reported an externalised LOC at age 8 were at increased risk of reporting both broadly defined (OR 1.77, 95% CI 1.49 to 2.08) and narrowly defined (OR 2.06, 95% CI 1.58 to 2.67) psychotic symptoms at age 13 years. These associations were only slightly attenuated after adjustment for potential confounders. The associations were similar for broadly defined specific paranoid symptoms but weaker for narrowly defined specific paranoid symptoms. CONCLUSIONS. An externalised LOC appears to be associated with later reporting of psychotic symptoms in early adolescence. Further investigation of the role of attributional styles, such as LOC, in increasing the risk for psychotic disorders, is warranted.