Age effects on Wechsler Adult Intelligence Scale-III subtests.

This investigation extended work on the Wechsler Adult Intelligence Scaled-Revised (WAIS-R) to the WAIS-III by determining how allotments of scaled-score points change with age, and to evaluate WAIS-III performance in terms of the Horn-Cattell constructs of crystallized and fluid intelligence. The age norms for the 14 individual WAIS-III subtests indicate that additional scaled-score points are awarded primarily to the Letter-Number Sequencing subtest of the Verbal Scale and to the seven Performance Scale subtests at ages 45 to 89 years for the same performance as individuals in the 20- to 34-year-old reference group. Subtests that measure speed of information processing showed more of a decline than subtests that measure verbal processing. Results are consistent with the view that measures of fluid intelligence show more of a decline with advancing age than do measures of crystallized intelligence. Published by Elsevier Science Ltd