The Cognitive Structure of the WPPSI-IV: What Can Network Analysis Tell Us?

The Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV), is widely used to assess young children’s cognitive abilities. Its indices describe performance in domains such as verbal comprehension and working memory, but evidence for interpreting these as distinct abilities remains limited. This study examined whether exploratory graph analysis (EGA), a network method, could recover the proposed index groupings from published normative correlations for ages 2:6 to 3:11 (n = 600) and 4:0 to 7:7 (n = 1,100). Simulations tested whether the same method could recover those groupings when separate, correlated factors generated the data. The main EGA procedure placed the primary subtests in one group. It also produced one group in 99.6% to 100% of samples generated from the index models, so it could not distinguish those models from simpler alternatives. In the older band, however, factor models fit better with several factors than with one. Recovery depended on factor correlations, the number of subtests per factor, and a built-in check for a single dimension. Groupings also changed with subtest coverage. For school psychologists, a one-group network result, however consistent, cannot by itself show whether WPPSI-IV index scores reflect distinct abilities.