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Mental retardation

Synonym(s)

  • mental handicap
  • MR - mental retardation

Definition(s)

Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual is mentally retarded. IQ scores between 70 and 79 are in the borderline mentally retarded range. Scores below 67 are in the retarded range.

Definition from: MeSH via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

Subaverage intellectual ability that is equivalent to or less than an IQ of 70, is present from birth or infancy, and is manifested especially by abnormal development, by learning difficulties, and by problems in social adjustment

Definition from: Merriam-Webster's Medical DictionaryThis link leads to a site outside Genetics Home Reference. by Merriam-Webster Inc.

Related discussion in the Handbook

See also Understanding Medical Terminology.

 
Published: July 7, 2014