Psychomotor traits, social desirability and the personal illness hierarchy.

Seventy-eight psychiatric in-patients were allocated to personal illness classes by means of the Delusions-Symptoms-States Inventory (DSSI). Paper and pencil measures of psychomotor speed and scatter of tapping were administered with an immediate retest. It is suggested that from a social desirability position one would have to predict that the more personally ill (i.e. those endorsing the more socially undesirable items) would be slower and more diffuse on these measures. We found, however, such patients to be more constricted and slower. It is concluded that such a combination adds to the utility and validity of the hierarchy of classes of personal illness.