Can the MABC discriminate and predict motor impairment? A comparison of Brazilian and American children

Abstract

Background: Estimates of the prevalence of developmental coordination disorder range from 1.7% to 19%, raising concerns about the discriminative ability of the Movement Assessment Battery for Children (MABC). Aims: We compared MABC performance of children aged 4–12 years from the USA and Brazil. We aimed to examine: a) the prevalence of motor impairment across countries; b) age band and sex differences across countries; c) the test's ability to discriminate and predict motor impairment; and d) to identify the discriminating capacity of each MABC subtest. Methods: Children (n=1055) from Brazil and the USA were included in the present study. MABC cut-off points (typical development: above 15%, at risk: 6–15%; developmental coordination disorder: 0–5%) and discriminant analyses were used. Findings: Prevalence of probable developmental coordination disorder (24.1%) and at risk (16.2%) was higher in the Brazilian sample. Higher prevalence of probable developmental coordination disorder was observed among girls and among children aged 11–12 years old for the Brazilian sample and among boys and among children aged 9–12 years old for the American sample. Differences in scores across countries were only observed for children with typical development in manual dexterity and balance skills. The MABC discriminant functions were able to predict the classification of children into typical development, at risk, and probable developmental coordination disorder. The manual dexterity subtest was the strongest predictor for both samples, whereas the ball skills subtest was the weakest predictor. Conclusions: Differences for prevalence were found across countries. American results were similar with current estimates relative to incidence and gender; for Brazilian children, prevalence was near three times higher and more persistent among girls. Overall, in both countries the motor difficulties demonstrated by children with probable and at risk of developmental coordination disorder were similar for all tasks. The MABC showed predictably and discriminant capacity in the identification of children with probable and at risk developmental coordination disorder in both countries.