Hand movement quality: a neglected aspect of nonverbal behavior in clinical judgment and person perception

Hand movement quality, the way in which human hand movements are executed in terms of circumference, velocity, and acceleration, seems to be very important both in terms of clinical diagnosis and in everyday person perception. This research studied movement quality by using objective physical measurements of movement parameters and subjective movement quality judgments and by comparing both approaches in terms of reliability and validity. This is done on the basis of clinical behavior samples that compared movements of psychiatric patients before and after therapy (N = 20). Results indicate that subjective judgments of movement quality are used reliably by lay judges and that these judgments are related closely to objective movement parameters. Some characteristics of movement quality seem to be important cues in clinical judgments of patients' improvement, although, objectively, movements do not differ before and after successful therapy.