Tests of Measurement Invariance of Three Wechsler Intelligence Tests in Economically Developing Nations in South Asia and Sub-Saharan Africa

Tests of measurement invariance are essential to determining whether individual scores or group averages are comparable across populations. While international comparisons of mean IQ scores are common, tests of measurement invariance for intelligence test batteries (necessary for comparisons to be empirically supported) are rare. In this study, four archival sets of Wechsler test IQ scores from Ghana, Kenya, Pakistan, and Sudan were tested for measurement invariance when compared to the American norm data for the same tests. Results indicate that two datasets - from Ghana and Kenya - demonstrated strict measurement invariance. However, the other two data sets failed to meet the requirements of scalar or strict measurement invariance, which indicates that global IQ scores from these latter data sets cannot be compared to American IQ scores on the same tests. Tests of measurement invariance should be regularly conducted when making comparisons of scores between industrialized and economically developing nations.