Peralta V, Cuesta M J, Martinez-Larrea A, Serrano J F
Psychiatric Unit, Virgen del Camino Hospital, Irunlarrea 4, 31008, Pamplona, Spain.
Psychiatry Res. 2001 Dec 15;105(1-2):97-105. doi: 10.1016/s0165-1781(01)00319-5.
A three-factor structure of schizophrenic symptoms has received considerable support, but there are no data on the factor structure of symptoms in neuroleptic-naive patients and how symptoms evolve after the inception of antipsychotic treatment. Seventy neuroleptic-naive patients with schizophrenia or related psychotic disorders were assessed with the Scales for the Assessment of Positive and Negative Symptoms before and after neuroleptic treatment. Ten global ratings of symptoms were subjected to factor analysis at the two time points and the factor solutions compared. A three-factor structure composed of psychotic, disorganization, and negative dimensions was found at the two assessment points. The negative and disorganization factors were highly correlated at each assessment and across assessments. While the symptom composition of the factors at the neuroleptic-naive assessment fitted that described in most previous studies, the composition of the negative and disorganization factors after neuroleptic treatment was somewhat different in that attention and inappropriate affect loaded on the negative factor instead of the disorganization factor. It is concluded that caution is warranted when using the three-factor model of schizophrenic symptoms as it may not be stable at different phases of the illness.