Parent-completed developmental screening in a Norwegian population sample: A comparison with US normative data

Abstract

Aim: To compare normative data of a Norwegian translation of the Ages and Stages Questionnaires with original US normative data. Methods: Norwegian-born mothers randomly selected from the population register completed Norwegian translations of the Ages and Stages Questionnaires, a series of 19 age-specific child development screening questionnaires each made up of 30 items in five domains: Communication, Gross Motor, Fine Motor, Problem Solving, and Personal-Social. Domain score group differences with original US normative data on 10 age-specific questionnaires (for ages 4, 8, 12, 16, 20, 24, 30, 36, 48, and 60 mo) were investigated. The Norwegian data consisted of 1341 children, varying between 82 and 176 per age interval. Results: On the whole, parents' reports of their children's development were very similar in the two data sets. Only five out of 50 mean comparisons revealed a mean difference either greater than a Cohen's d of 0.5 or greater than the smallest increment on a domain score. The variation in scores tended to be somewhat smaller in the Norwegian sample. Conclusion: It seems reasonable to expect that domain scores on the Ages and Stages Questionnaires may be interpreted in the same way in Norway and the United States, and these results may also generalize to other Western settings. These findings from a true random sample also increase the confidence in the original normative data.