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Black Americans reduce the racial IQ gap: evidence from standardization samples
William T Dickens1, James R Flynn
1Economic Studies, Brookings Institution, Washington, DC, USA.
Psychological Science
|November 15, 2006
Summary
Black Americans have shown significant IQ gains compared to non-Hispanic Whites. Analysis of cognitive ability tests from 1972-2002 indicates a 4-7 point increase, challenging previous assumptions.
Area of Science:
- Psychometrics
- Cognitive Psychology
- Sociology of Race
Background:
- Historical assertions claim no IQ gains for Black Americans relative to White Americans.
- Lack of adequate longitudinal data previously hindered trend analysis.
Purpose of the Study:
- To investigate IQ score trends between Black and non-Hispanic White Americans.
- To determine if Black Americans have made cognitive gains over recent decades.
Main Methods:
- Analysis of nine standardization samples from four major cognitive ability tests.
- Longitudinal data collection spanning from 1972 to 2002.
Main Results:
- Black Americans demonstrated an average IQ gain of 4 to 7 points compared to non-Hispanic Whites.
- These cognitive gains were observed uniformly across all levels of Black cognitive ability.
Conclusions:
- The study provides empirical evidence of Black IQ gains, contradicting prior assumptions.
- Cognitive development trends suggest a narrowing of the IQ gap between racial groups.
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