[Negative symptoms of schizophrenic patients from the perspective of psychiatrists, patients themselves and their relatives].

Clinical experience shows that negative symptoms are affected by environmental factors. Thus, different assessors with different information about patient behavior in different environments may come to different findings of negative symptoms. In this regard, the present study evaluates to what extent the assessment of negative symptoms by schizophrenic inpatients and their relatives compares to interview-based assessments by experts. Therefore, 33 schizophrenic patients were rated by patients themselves, their relatives, and psychiatrists. Negative symptoms were assessed with comparable assessment scales using the modified version of the Scale for the Assessment of Negative Symptoms (SANS) for patients or relatives and the original SANS for psychiatrists. Analyses revealed that the total SANS summary scores as rated by patients and relatives were comparable to scores rated by psychiatrists. Scores on SANS subscales of "alogia" and "attention deficits" differed significantly among the three ratings, while psychiatrists rated the patients' impairments as lower than did the patients themselves or their relatives. These findings indicate that patients' and relatives' ratings could be used to reduce information variance and improve the validity of interview-based, assessed negative symptoms.