DSM-IV & DSM-IV-TR:

Mental Retardation

This mental disorder is diagnosed in individuals who, from whatever cause, have intelligence below an arbitrary level beginning before adulthood and whose adaptive functioning is impaired in any of a variety of areas.

Diagnostic criteria for Mental Retardation
(cautionary statement)

A. Significantly subaverage intellectual functioning: an IQ of approximately 70 or below on an individually administered IQ test (for infants, a clinical judgment of significantly subaverage intellectual functioning).

B. Concurrent deficits or impairments in present adaptive functioning (i.e., the person's effectiveness in meeting the standards expected for his or her age by his or her cultural group) in at least two of the following areas: communication, self-care, home living, social/interpersonal skills, use of community resources, self-direction, functional academic skills, work, leisure, health, and safety.

C. The onset is before age 18 years.

Code based on degree of severity reflecting level of intellectual impairment:

317 Mild Mental Retardation: IQ level 50-55 to approximately 70

318.0 Moderate Mental Retardation: IQ level 35-40 to 50-55

318.1 Severe Mental Retardation: IQ level 20-25 to 35-40

318.2 Profound Mental Retardation: IQ level below 20 or 25 319 Mental Retardation, Severity Unspecified: when there is strong presumption of Mental Retardation but the person's intelligence is untestable by standard tests

Also: developmental disability