Systematic dyskinesia examination of profoundly mentally retarded persons: cooperation and assessment.

Performance of 344 institutionalized mentally retarded adults was measured to assess the applicability of the Dyskinesia Identification System Condensed User Scale. A larger proportion of profoundly retarded persons cooperated with Dyskinesia Identification examination procedures than has previously been found. Performance deficits were observed on activation tasks (APA, 1979) that precede assessment of lingual abnormal involuntary movements. Intelligence quotients, neuroleptic dosage, gender, and ambulatory and visual impairments were associated with performance of activation tasks. Results suggest the difficulty of implementing standardized tardive dyskinesia assessments and that client behavior problems may threaten the valid assessment of this disorder among institutionalized profoundly retarded persons.