Hierarchy of classes of personal illness.

A hierarchy of classes of personal illness model is proposed and was assessed using a new self-report measure, the Delusions-Symptoms-States Inventory (DSSI). Of 480 psychiatric patients 93.3% had a symptom patterns conforming to the model. It was additionally found that single syndrome patterns, within a particular class, occurred significantly more often than those not classifiable in any higher class. Finally, the relationship between each possible pair of the 12 syndromes was examined. Some of the implications of the model and the data are discussed in terms of the development, remission, assessment, and treatment of personal illness.