Integrating health, education and culture in predicting Pacific children's English receptive vocabulary at 6 years: A classification tree approach.

Abstract

Pacific children fare poorly on health and educational outcomes, including literacy. Early interventions are considered critical in reducing educational disparities. A prediction model was constructed to analyse the factors associated with Pacific children's English receptive vocabulary, an important component of English language development. A birth cohort study of Pacific children was used to construct a classification tree model and predict the proportions of Pacific children who performed strongly in a standardised test of English receptive vocabulary at 6 years of age (n = 1019). Classification trees were constructed using 10-fold cross-validation (CV) and pruned using the one-standard-error rule. Prediction errors were directly estimated using leave-one-out CV. Analyses of misclassification errors from the pruned model gave false negative and positive rates of 19 and 19% from re-substitution and 54 and 21% from leave-one-out CV estimation, respectively. Of the predictors, maternal acculturation, small birthweight and performance in early developmental screening test at 4 years of age were found to have the highest goodness of split. The cultural environment to which Pacific children were exposed in early childhood, indicated by the maternal acculturation, was more crucial in distinguishing children with strong English-receptive vocabulary skills than socio-economic or prenatal conditions. This highlights the importance of integrating the cultural environment into designing measures for facilitating Pacific children's language development.