Self-rated schizotypal cognitions, psychotic symptoms and the onset of schizophrenia in young people at high risk of schizophrenia.

Abstract

To examine the associations between the Rust Inventory of Schizotypal Cognitions (RISC) and psychotic symptoms measured by the Present State Examination (PSE) and to assess the predictive validity of the RISC for later onset of schizophrenia. A total of 154 subjects at high risk for schizophrenia but who were currently well, 35 well controls and 28 first episode schizophrenic patients were assessed on specified PSE symptoms and completed the RISC. A subsample of the high risk group was subsequently monitored for onset of schizophrenia over 39 months. RISC scores at entry were significantly higher in subjects with psychotic symptoms on PSE. There were indications that high scorers on the RISC were likely to develop schizophrenia. However, less than half of those falling ill exhibited high RISC scores on entry. The RISC scale is highly associated with presence of psychotic symptoms on PSE and high scorers may be at increased risk of schizophrenia onset.