Locus of control and mental health in adolescence and adulthood.

Eighty-nine subjects of the original sample of the National Institute of Mental Health joint study by the United States and Israel, known as the Israeli High-Risk Study, were given a clinical interview and a questionnaire measuring locus of control (LOC) during the second phase of the study, when the subjects were adolescents. During phases 3 and 4, approximately 8 and 15 years later, the subjects were psychiatrically assessed and 56 of them repeated the LOC questionnaire. The two measures of LOC were correlated, as were general assessments of mental health (MH). Adolescent LOC was related to lifetime MH, although LOC and MH were not related to each other concurrently in either adolescence or adulthood. The best predictive model for lifetime MH outcomes was a combination of adolescent MH and LOC variables; background variables, including parental schizophrenia, were superfluous. The data suggest that whereas adolescent MH is the best predictor of general MH, adolescent LOC is the better predictor of schizophrenia and major affective disorders.