Objective: To examine the diagnostic value of self-reported psychotic-like experiences for DSM-III-R psychotic disorders.
Method: A general population sample of 7076 subjects aged 18–64 years was interviewed with the Composite International Diagnostic Interview (CIDI) and, if there was evidence of psychotic experiences, the Structured Clinical Interview for DSM-III-R.
Results: The probability of having a psychotic disorder increased in a dose–response fashion with the level of self-reported psychotic experiences, but individual CIDI psychotic experience ratings had relatively low post-test probabilities (PPs) (range: 5.1–26.5%). However, limiting the sample to individuals who had been in contact with mental health services substantially improved PPs (range: 13.3–43.1%).
Conclusion: Screening for psychosis in the population carries a high risk of stigmatization in false-positive cases and violation of the right ‘not to know’ in true-positive cases. However, in mental health care users, self-reported psychotic experiences may be a useful screening tool in individuals who have already developed help-seeking.