Correlates of positive and negative schizophrenic syndromes in Nigerian patients.

The two-syndrome concept of schizophrenia was investigated in a sample of 70 Nigerian schizophrenic patients. The positive and negative syndromes were studied in relation to demographic, historical, neurological and psychometric measures. The negative syndrome was associated with cognitive impairment, behavioural deterioration and left eye dominance, and also with poor pre-morbid educational achievement and longer length of current stay in hospital. The positive syndrome was unrelated to any of the independent variables. The two syndromes were not significantly related, supporting the view that they represent relatively independent dimensions of pathology. This provides further support for the validity of the Type I-Type II subtyping of schizophrenia in populations of patients from different cultural backgrounds, and suggests that the negative syndrome is related to the presence of neurodevelopmental deficits that possibly antedate the schizophrenic illness.