Cultural Bias in Intelligence Assessment Using a Culture-Free Test in Moroccan Children

Previous research has shown that cognitive tests can lead to misclassification when applying non-representative norms to measure cognitive performance. The objective of this study was to investigate whether this misclassification also occurs with a non-verbal so-called "culture-free" intelligence test administered to different age groups.

The intelligence of a sample of healthy Moroccan children (N = 147) ages 7, 9, and 11 was assessed using the Coloured Raven's Progressive Matrices (CPM). Raw scores were used to study age differences, as well as misclassifications when applying the norms of three countries culturally different from Morocco (United Kingdom, Spain, and Oman).

Intelligence performance was not within the normal range when non-representative norms were applied to the Moroccan raw scores. Misclassifications accounted for a large percentage of the participants that supposedly displayed intelligence deficits, especially when applying the British norms. Up to 15.68% of the healthy children fell within the "intellectually impaired" range, and up to 62.5% fell "below average," with these percentages especially higher at older ages.

Our findings confirm that "culture-free" tests should be adapted to each culture and applied together with their culture's specific norms to prevent misclassification and allow for a better, unbiased neuropsychological assessment.