Convergent Validity of the Reynolds Intellectual Assessment Scales (RIAS) Using the Woodcock-Johnson Tests of Cognitive Ability, Third Edition (WJ-III) With University Students

Validity studies with the Reynolds Intellectual Ability scales (RIAS) indicated that RIAS composite intelligence index (CIX) and verbal intelligence index (VIX) scores have moderate-to-high correlation with comparable scores on other instruments. The authors of the RIAS described the VIX scale as a measure of crystallized ability and the nonverbal index (NIX) as a measure of fluid ability, but no studies were available comparing the VIX and NIX scores with an established measure of these abilities, nor studies specifically addressing the utility of the RIAS with a university population. The study examined RIAS scores of university students in comparison to scores on the Woodcock-Johnson Tests of Cognitive Ability (third edition; WJ-III). Consistent with previous studies, there were moderate-to-high correlations between the CIX and VIX scores and corresponding scores on the WJ-III. A substantially lower correlation was evident between the NIX and WJ-III fluid ability scores.