ACT and general cognitive ability

Research on the SAT has shown a substantial correlation with measures of g such as the Armed Services Vocational Aptitude Battery (ASVAB). Another widely administered test for college admission is the American College Test (ACT). Using the National Longitudinal Survey of Youth 1979, measures of g were derived from the ASVAB and correlated with ACT scores for 1075 participants. The resulting correlation was .77. The ACT also shows significant correlations with the SAT and several standard IQ tests. A more recent sample (N = 149) consisting of ACT scores and the Raven's APM shows a correlation of .61 between Raven's-derived IQ scores and Composite ACT scores. It appears that ACT scores can be used to accurately predict IQ in the general population.