Differences in young children's IQs on the Wechsler preschool and primary scale of intelligence-revised as a function of stratification variables.

The normative sample (N = 1,700) of the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), stratified on age, gender, ethnicity, geographic region, education, and occupation of children's parents, served as the database with which to examine the associations of demographic characteristics with Verbal Intelligence Quotients (VIQs), Performance Intelligence Quotients (PIQs), and Full Scale Intelligence Quotients (FSIQs) among young children. A 3-way multivariate analysis of variance (MANOVA) andfollow-up analyses of variance (ANOVAs) found significant effects of parent education and ethnicity, but not child's gender, on IQ. A separate 2-way MANOVA andfollow-up ANOVAsfound significant interaction effects between region and ethnicity on IQ. Parent education showed the largest association with all 3 IQs, whereas gender and age showed the least. The meaning of the hierarchy of the stratification variable associations with IQ is discussed.