Emotional disturbance in mental retardation: an investigation of differential diagnosis.

The study sought to determine whether 100 emotionally disturbed mentally retarded subjects assigned four distinct diagnostic labels could be differentiated from each other on the basis of sex, age, degree of mental impairment, and adaptive behavior. Univariate and multivariate analyses indicated that the autism classification was distinguishable from psychosis, schizophrenia, and severe emotional disturbance in terms of degree of retardation and adaptive behavior. The primary distinguishing feature was the autistic group's low level of language development. The schizophrenics, psychotics, and severely emotionally disturbed subjects were indistinguishable from each other on the variables examined.