Negative symptoms and vocational impairment in schizophrenia: repeated measurements of work performance over six months.

Interest in negative symptoms as a dimension of schizophrenia has grown dramatically in the last decade. One hypothesized correlate of negative symptoms that has received less attention is deteriorated work function. To address this issue, this study compared biweekly measurements of work performance for 21 patients with prominent negative symptom and 29 patients without prominent negative symptoms enrolled in a 26-week supported work program. Nonparametric analysis indicated that subjects with prominent negative symptoms demonstrated poorer performance than other subjects on task orientation, social skills and personal presentation. No evidence was found that the work performance of either group improved or worsened over time, although a trend suggested that social skills may have improved slightly for both groups across the 26 weeks. These results support hypotheses linking negative symptoms with deteriorated work function.