VALIDITY OF THE COMPOSITE INTERNATIONAL DIAGNOSTIC INTERVIEW (CIDI) PSYCHOSIS MODULE IN A PSYCHIATRIC SETTING

This study aimed to test the procedural validity of the psychosis modu le of the Composite International Diagnostic Interview (CIDI) by compa ring it with diagnostic checklists completed by experienced clinicians . Seventy-five subjects were interviewed using the interviewer-adminis tered version of the CIDI. Their clinician(s) then completed diagnosti c checklists for DSMIV and ICD10 diagnoses of schizophrenia. Agreement was measured at the diagnostic, criterion and subcriterion levels. Th e validity standard (diagnostic checklist) was shown to be reliable wi th interrater agreement between the clinicians for the diagnosis of sc hizophrenia being excellent (kappa = 0.82 for DSMIV and kappa = 0.71 f or ICD10). The agreement between the CIDI and the clinician checklists varied with sensitivities for DSMIV subcriteria ranging from 0.18 (ne gative symptoms) to 0.93 (bizarre delusions) and specificities ranging from 0.38 (catatonia) to 0.95 (disorganised speech). A similar patter n was found for ICD10 subcriteria: sensitivity varied from 0.19 (neolo gisms) to 0.90 (persistent delusions) and specificity varied from 0.39 (catatonia) to 0.95 (negative symptoms). The poorest levels of agreem ent were found for symptoms requiring interviewer judgement. The CIDI showed good agreement with clinician checklist diagnoses when the crit eria were based on questions asked of the subjects. When the interview er was required to make judgement of behaviours, the agreement between the CIDI and the clinician checklists was lower, resulting in overall poor agreement between the CIDI and the clinician checklists. Suggest ions for improving the validity of the psychosis module of the CIDI ar e made. (C) 1998 Elsevier Science Ltd. All rights reserved.