A comparison of information sources in the study of psychotic illness

The clinical features shown by 50 psychotic patients were documented by interviews held with the patient and next-of-kin, brief videotaped interviews and nurse rating in addition to the hospital case record. Three raters studied all the available material and made master ratings. Comparison of the ratings made at mental state interview with these master ratings showed that this interview missed a great deal of the pathology agreed to be present. The interview with the next-of-kin was helpful in identifying manic symptoms. Nurse rating based on an 8-hour period of observation was less effective overall, but highly significant associations with the master ratings were achieved in 29/57 areas studied. In four areas (uncooperative behaviour, concern for others, agitation and distractibility) it was superior to either interview.