Age-related change in Wechsler IQ norms after adjustment for the Flynn effect: estimates from three computational models.

A previous study found that the Flynn effect accounts for 85% of the normative difference between 20- and 70-year-olds on subtests of the Wechsler intelligence tests. Adjusting scores for the Flynn effect substantially reduces normative age-group differences, but the appropriate amount of adjustment is uncertain. The present study replicates previous findings and employs two other methods of adjusting for the Flynn effect. Averaged across models, results indicate that the Flynn effect accounts for 76% of normative age-group differences on Wechsler IQ subtests. Flynn-effect adjustment reduces the normative age-related decline in IQ from 4.3 to 1.1 IQ points per decade.