Elsevier

Intelligence

Volume 38, Issue 1, January–February 2010, Pages 1-20
Intelligence

A systematic literature review of the average IQ of sub-Saharan Africans

https://doi.org/10.1016/j.intell.2009.05.002Get rights and content

Abstract

On the basis of several reviews of the literature, Lynn [Lynn, R., (2006). Race differences in intelligence: An evolutionary analysis. Augusta, GA: Washington Summit Publishers.] and Lynn and Vanhanen [Lynn, R., & Vanhanen, T., (2006). IQ and global inequality. Augusta, GA: Washington Summit Publishers.] concluded that the average IQ of the Black population of sub-Saharan Africa lies below 70. In this paper, the authors systematically review published empirical data on the performance of Africans on the following IQ tests: Draw-A-Man (DAM) test, Kaufman-Assessment Battery for Children (K-ABC), the Wechsler scales (WAIS & WISC), and several other IQ tests (but not the Raven's tests). Inclusion and exclusion criteria are explicitly discussed. Results show that average IQ of Africans on these tests is approximately 82 when compared to UK norms. We provide estimates of the average IQ per country and estimates on the basis of alternative inclusion criteria. Our estimate of average IQ converges with the finding that national IQs of sub-Saharan African countries as predicted from several international studies of student achievement are around 82. It is suggested that this estimate should be considered in light of the Flynn Effect. It is concluded that more psychometric studies are needed to address the issue of measurement bias of western IQ tests for Africans.

Section snippets

Scholastic achievement surveys

In several studies (Lynn, 2006, Lynn et al., 2007, Lynn and Mikk, 2007, Lynn and Vanhanen, 2006, Rindermann, 2007), Lynn and Vanhanen's estimates of national IQ were correlated with data from several internationally comparable surveys of school achievement (e.g., TIMMS, PISA). In these surveys representative samples of primary and secondary students were given reading, mathematics, or science tests. These studies have quite clearly shown that national IQs and the means for countries from these

A systematic review of the literature

In this section, we present the results of a systematic review of published studies in which western IQ tests (i.e., IQ tests developed and standardized in western countries) were administered to Black sub-Saharan Africans. Lacking of more specific data our emphasis is necessarily on overall (average) performance. Given the available data, we cannot do justice to the wide cultural and economic differences of the many and varied peoples on this continent. Nonetheless, we hope that our review may

Search of studies

In early 2009, we employed PsycINFO to search for additional studies of IQ test performance of Africans. We used the following search terms: “IQ”, “intelligence”, “cognitive ability”, “abilities” combined with the countries' names and adjectives as well as the words “Africa”, “African”. This resulted in approximately 2800 unique references that were scanned for relevance. Because the Draw-a-Man test is administered often in Africa, we also searched for additional data of this test by using the

Results

All samples are reported in Table 2, along with our assessments of whether or not these samples meet our inclusion criteria. We now discuss all samples per test, starting with those most commonly used in Africa.

Conclusion

The assertion that the average IQ of Africans is below 70 is not tenable, even under the most lenient of inclusion criteria. The inclusion of all studies in Table 2 results in an estimate of an average IQ of 77. This estimate represents an underestimate of the true average IQ, because it is based on (1) inaccurate (often ad hoc) IQ norms or norms based on mental-age IQs, (2) IQ tests that were not administered according to official guidelines (e.g., adapted), (3) studies of IQ in which the test

References (150)

  • HuntE.B. et al.

    Sorry, wrong numbers: An analysis of a study of a correlation between skin color and IQ

    Intelligence

    (2006)
  • HuntE.B. et al.

    National intelligence and national prosperity

    Intelligence

    (2008)
  • KanazawaS.

    Temperature and evolutionary novelty as forces behind the evolution of general intelligence

    Intelligence

    (2008)
  • KashalaE. et al.

    Cognition in African children with attention-deficit hyperactivity disorder

    Pediatric Neurology

    (2005)
  • KhaleefaO. et al.

    The increase of intelligence in Sudan 1964–2006

    Personality and Individual Differences

    (2008)
  • LoehlinJ.C.

    Book review: R. Lynn Race differences in intelligence

    Intelligence

    (2007)
  • LynnR.

    The geography of intelligence

  • LynnR. et al.

    Average intelligence predicts atheism rates across 137 countries

    Intelligence

    (2009)
  • LynnR. et al.

    National differences in intelligence and educational attainment

    Intelligence

    (2007)
  • LynnR. et al.

    National IQs predict educational attainment in math, reading and science across 56 nations

    Intelligence

    (2009)
  • McDanielM.A.

    Book review. R. Lynn & T. Vanhanen (2006). IQ and global inequality

    Intelligence

    (2008)
  • MellenberghG.J.

    Item bias and item response theory

    International Journal of Educational Research

    (1989)
  • MorseS.

    Making development simple. The genetic deterministic hypothesis for economic development

    Ecological Economics

    (2006)
  • AkandeA.

    Order effects on neuropsychological test performance of normal, learning disabled and low functioning children: A cross-cultural study

    Early Child Development and Care

    (2000)
  • AladeE.B.

    Determining intelligence coefficients of Nigeria deaf children with the Wechsler Intelligence Scale for Children—Revised

    Early Child Development and Care

    (1992)
  • AshemB. et al.

    Deleterious effects of chronic undernutrition on cognitive abilities

    Journal of Child Psychology and Psychiatry

    (1978)
  • AvenantT.J.

    The establishment of an individual intelligence scale for adult South Africans

  • BadriM.B.

    Influence of modernization on Goodenough quotients of Sudanese children

    Perceptual and Motor Skills

    (1965)
  • BadriM.B.

    The use of finger drawing in measuring the Goodenough quotient of culturally deprived Sudanese children

    Journal of Psychology

    (1965)
  • BakareC.G.M.

    Social-class differences in the performance of Nigerian children on the Draw-a-Man test

  • BardetC. et al.

    Application de test de Goodenough à des écoliers africains de 7 à 14 ans [Application of the Goodenough test to African school children ages 7 to 14]

    Enfance

    (1960)
  • BarnettS.M. et al.

    National intelligence and the emperor's new clothes

    Contemporary Psychology

    (2004)
  • BartholomewD.J.

    Measuring intelligence. Facts and fallacies

    (2004)
  • BerryJ.W.

    Radical cultural relativism and the concept of intelligence

  • BiesheuvelS.

    African intelligence

    (1943)
  • BoivinM.J.

    Effects of early cerebral malaria on cognitive ability in Senegalese children

    Journal of Developmental and Behavioral Pediatrics

    (2002)
  • BoivinM.J. et al.

    Improvements in cognitive performance for schoolchildren in Zaire, Africa, following an iron supplement and treatment for intestinal parasites

    Journal of Pediatric Psychology

    (1993)
  • BoivinM.J. et al.

    Use of the tactual performance test for cognitive ability testing with African children

    Neuropsychology

    (1995)
  • BoivinM.J. et al.

    Effects of treatment for intestinal parasites and malaria on the cognitive abilities of schoolchildren in Zaire, Africa

    Health Psychology

    (1993)
  • BurosO.K.

    The fifth mental measurements yearbook

    (1959)
  • CarlsonJ.S.

    A note on the relationship between the Draw-a-Man test, the progressive matrices, and conservation

    Journal of Psychology

    (1970)
  • CattellR.B. et al.

    Culture Fair Intelligence Test Scale 2

    (1973)
  • ClaassenN.C.W. et al.

    A standardisation of the WAIS-III for English-speaking South Africans

    (2001)
  • CooperH.

    Synthesizing research. A guide for literature review

    (1998)
  • CooperH.

    Editorial

    Psychological Bulletin

    (2003)
  • Crawford NuttD.H.

    Are Black scores on Raven's Standard Progressive Matrices an artifact of method of test presentation?

    Psychologia Africana

    (1976)
  • DentG.R.

    The educability of the Bantu

  • DolanC.V.

    Investigating Spearman's hypothesis by means of multi-group confirmatory factor analysis

    Multivariate Behavioral Research

    (2000)
  • DuvalS.

    The trim and fill method

  • DuvalS. et al.

    Trim and fill: A simple funnel-plot-based method of testing and adjusting for publication bias in meta-analysis

    Biometrics

    (2000)
  • Cited by (93)

    • Dodging Darwin: Race, evolution, and the hereditarian hypothesis

      2020, Personality and Individual Differences
    View all citing articles on Scopus

    The preparation of this article was supported by VENI grant no. 451-07-016 from the Netherlands Organization for Scientific Research (NWO) awarded to JMW. We thank three anonymous reviewers for their insightful comments.

    View full text