This study tested competing interpretations of I& deficit in schizophrenic patients. One interpretation (concomitancy hypothesis) holds that I& loss is a product of schizophrenic symptoms and is remedied as the symptoms remit. The second (prodromal hypothesis) holds that I& deficit preceeds and facilitates the development of schizophrenic disorder and is not remedied with symptom remission. The IQs cf schizophrenic patients were obtained before and three times after hospital treatment. All mean IQs fell within average limits and did not increase significantly after treatment, although test-retest correlations suggested slight disruption of IQ in the morbid state. Remitting cases did not differ significantly from nonremitting cases. Paradoxically, chronic patients earned slightly higher IQs than acute patients. The findings are inter reted as providing some suppcrt for both interpretations of schizophrenic ? Q deficit. I t is concluded that the specific I& tests used and the nature of the patient samples tested will have a significant bearing on which hypothesis is supported in individual studies of schizophrenic IQ deficit.
Clinical lore maintains that schizophrenic patients suffer I& loss in the morbid state, and the results of several empirical studies support the clinical observations. Winder (1960) reviewed early research and concluded that schizophrenics tend to earn I& scores that average about 10 points below the national mean of 100. Studies reported since Winder's review also have documented an average 10-point I&