Factor analysis of delusional disorder symptomatology.

Delusional disorder symptomatology has been poorly investigated with factor analytic studies. Most attempts to identify its symptomatologic structure were made with schizophrenic or mixed psychotic populations and included only delusional symptoms. The purpose of this study was to analyze the whole symptomatologic structure of delusional disorder. One hundred eight inpatients with delusional disorder (DSM-III-R) were evaluated for lifetime symptoms using the Operational Criteria (OPCRIT) checklist for psychotic illness and included in a factorial analysis. Four factors were evaluated: (1) core depressive symptoms, (2) hallucinations, (3) delusions, and (4) irritability symptoms. Thus, when scored by the OPCRIT checklist, delusional symptomatology consisted of four independent factors, indicating a substantial heterogeneity of this diagnostic category.