Symptom dimensions in recent-onset schizophrenia and mania: a principal components analysis of the 24-item Brief Psychiatric Rating Scale

Previous four- and five-factor solutions of the 18-item Brief Psychiatric R ating Scale (BPRS) suggested the possibility of an affective dimension in p sychosis. A principal components analysis was used to analyze psychiatric s ymptom data rated on an expanded 24-item version of the BPRS. BPRS data wer e collected during a period of acute psychotic and affective illness with 1 14 young adult, recent-onset schizophrenia and schizoaffective patients and 27 bipolar manic patients. Principal components analyses of the 18-item an d 24-item BPRS indicated a four-factor solution was the most interpretable. Principal components analysis of the 24-item BPRS produced a clear mania f actor characterized by high loadings from items added to the 18-item BPRS, which included elevated mood, motor hyperactivity, and distractibility. Thi s factor solution suggests that the 24-item BPRS allows for an expanded ass essment of affective symptoms relating to a manic dimension. Potentially im portant symptoms that were added to the traditional 18-item version, namely suicidality, bizarre behavior, and seif-neglect, also make clear contribut ions to other factors. (C) 2000 Elsevier Science Ireland Ltd. All rights re served.