Some proposed that the Implicit Association Test measures individual differences in implicit social cognition; the claim requires evidence of construct validity; this author says there is insufficient evidence for this claim

The Implicit Association Test: A Method in Search of a Construct. Ulrich Schimmack. Perspectives on Psychological Science, October 24, 2019. https://doi.org/10.1177/1745691619863798

Abstract: In 1998, Greenwald, McGhee, and Schwartz proposed that the Implicit Association Test (IAT) measures individual differences in implicit social cognition. This claim requires evidence of construct validity. I review the evidence and show that there is insufficient evidence for this claim. Most important, I show that few studies were able to test discriminant validity of the IAT as a measure of implicit constructs. I examine discriminant validity in several multimethod studies and find little or no evidence of discriminant validity. I also show that validity of the IAT as a measure of attitudes varies across constructs. Validity of the self-esteem IAT is low, but estimates vary across studies. About 20% of the variance in the race IAT reflects racial preferences. The highest validity is obtained for measuring political orientation with the IAT (64%). Most of this valid variance stems from a distinction between individuals with opposing attitudes, whereas reaction times contribute less than 10% of variance in the prediction of explicit attitude measures. In all domains, explicit measures are more valid than the IAT, but the IAT can be used as a measure of sensitive attitudes to reduce measurement error by using a multimethod measurement model.

Keywords personality, individual differences, social cognition, measurement, construct validity, convergent validity, discriminant validity, structural equation modeling