The development of cognitive functioning indices in early childhood

A key difficulty in assessing cognitive development in early childhood lies in the necessity of using different measures for age groups over time. We report on the development of cognitive composite indices (CCIs) at 9 months, 2 years and 4.5 years in children enrolled in the Growing Up in New Zealand study. Data was collected from 6074 children comprising 21 age-adjusted cognitive outcomes. Factor analysis was performed, identifying one factor at 9 months and two factors at 2 years and 4.5 years, respectively. Only the CCIs identified at 4.5 years were significantly related to cognitive outcomes at 8 years. The scores identified in this study can potentially be used to observe rank order changes or movement of general cognitive abilities.

Automated summary

The study found that cognitive composite indices at 9 months, 2 years, and 4.5 years were differently related to cognitive outcomes at 8 years, with CCIs identified at 4.5 years having a better predictive power for future cognitive development.