Adult life-span patterns in WAIS-R Block Design performance: Cross-sectional versus longitudinal age gradients and relations to demographic factors

Aging patterns in WAIS-R Block Design Test (BDT) were examined cross-sectionally and longitudinally. One sample (35–80 years, n = 1000) was assessed in 1988–1990 and five years later (836 returned). An independent cohort-matched sample (n = 974) was assessed at Time 2 to control for practice effects. Relations between BDT, gender, and education were examined. The cross-sectional analyses indicated a gradual age-related deterioration from 35 to 85 years. By contrast, the longitudinal data indicated stable performance from age 35 to 55, even when minor practice effects were adjusted for, and decline past age 55. Education-adjusted cross-sectional differences revealed similar patterns. A minor, age- and time invariant, male advantage was observed. Education predicted time-related change in BDT, such that higher education was associated with lesser decline. Collectively, the results demonstrate the need to control for cohort and retest effects in cross-sectional and longitudinal studies, and reveal interesting relations between BDT performance and demographic variables.