Wechsler Preschool & Primary Scale of Intelligence | Fourth Edition Australian and New Zealand Standardised Edition (WPPSI-IV A&NZ) - is an innovative measure of cognitive development for pre-schoolers and young children, rooted in contemporary theory and research.  This edition also places a strong emphasis on child-friendly, developmentally appropriate features, and includes new processing speed tasks, the addition of working memory subtests and an expanded factor structure. These extensive enhancements are targeted to benefit both children and examiners.