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In 1973, AAMR set intellectual disability at about two standard deviations below average IQ.

The Claim

In 1973, the American Association on Mental Retardation changed the IQ cutoff for diagnosing mental retardation from below 85 to below 70 because more than half of African Americans scored below 85.

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The Short Version

The historical record supports the threshold change, but not the claimed racial motive. Reliable sources show the 1973 revision returned to a two-standard-deviation cutoff, removed the borderline category, and was associated with concerns about overidentifying minority students. No authoritative source shows the organization changed the standard specifically because more than half of African Americans scored below 85.

Caveats

  • The claim mixes a real historical change with an unsupported specific explanation for why it happened.
  • General concern about minority overidentification does not prove the specific causal claim about African Americans scoring below 85.
  • The organization in 1973 was the American Association on Mental Deficiency; later naming can obscure the historical record.

The Receipts

  1. Introduction - Mental Retardation

    NCBI Bookshelf (NIH)

  2. Chapter 4: Intellectual Disability

    OEN Manifold (University of Minnesota)

  3. AAMD: Classification in Mental Retardation

    Law.Resource.Org

  4. Twentieth-Century Definitions of Mental Retardation

    Minnesota Governor's Council on Developmental Disabilities

  5. The 1970s: Developmental Disabilities. Millions Cured by Redefinition.

    Minnesota Governor's Council on Developmental Disabilities

  6. History of the race and intelligence controversy

    Wikipedia

  7. Mental Retardation (ED473010)

    ERIC (U.S. Department of Education)

  8. Beyond Reason: Mental Retardation: An Overview

    Human Rights Watch

  9. Black Americans Reduce the Racial IQ Gap

    Brookings Institution

  10. Thirty Years of Research on Race Differences in Cognitive Ability

    Psychology, Public Policy, and Law (via University of Delaware PDF)

+ 15 more sources — see the full list on Lenz

Filed Under

African AmericansAmerican Association on Mental Retardation

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