Progressive Figure drawings in the developmental assessment of mentally retarded psychotics.

A Progressive Figure Drawing Test was assembled to delineate level of perceptual-motor development in patients with both developmental and psychiatric disorders. 63 mentally retarded psychotic adults were evaluated by this procedure and other measures of intellectual, social, and psychiatric functioning. The test's reliability and developmental hierarchy were supported, and significant differentiation among grades of retardation was noted. Strong correlates were obtained with the other developmentally based tests while its associations with indices of psychosis were significantly weaker or inconsequential. The findings suggested that this procedure may separate cognitive subnormality from abnormality related to psychosis. It was proposed that developmental assessment may provide a crucial perspective for clinical evaluation and research into mental retardation and psychosis.