The inter-rater and test-retest reliabilities of prodromal symptoms in first-episode psychosis

OBJECTIVE: As part of the DSM-IV field trial for psychotic disorders, the authors endeavoured to determine the reliability of the DSM-IV prodromal features for schizophrenia in a first-episode sample. METHOD: Fifty first-episode psychotic patients were assessed using a semi-structured instrument to determine the presence/absence of nine prodromal symptoms. Inter-rater reliability data were calculated for 25 of the patients, and test-retest data were calculated for the remaining 25 patients. RESULTS: Levels of reliability were poor. CONCLUSIONS: The results lend some support to American Psychiatric Association and World Health Organization decisions to omit specific criteria for prodromal features from their respective nosologies.