Validation of three dimensions of schizophrenic symptoms in a large unselected sample of patients.

A principal components analysis was conducted upon current symptoms and signs rated in a sample of 329 essentially unselected patients with schizophrenia. Three dimensions emerged clearly and closely resembled those previously described in smaller, more selected samples. The clearly defined psychotic dimensions were related in turn to: (i) other mental state variables; (ii) physical treatments administered; (iii) movement disorder; (iv) demographic and historical features; and (v) cognitive function. The correlates of the three dimensions were very different. The clarity of separation achieved in this investigation provides strong support for the view that the three psychotic dimensions of 'poverty', 'hallucinations and delusions' and 'disorganization' are valid and may well have different underlying pathophysiologies.