Executive function in children with and without developmental coordination disorder: A comparative study.

Background: Children with motor impairments also show poor performance in some executive functions' components. However, there is no consensus on which specific executive subdomain is more impacted.
Aim: The objective of this study was to compare executive functions in children with developmental coordination disorder (DCD), at risk for DCD (r-DCD), and in typically developing (TD) children.
Methods and Procedures: A sample of 397 children was assessed using the MABC-2. Two groups of children were identified; DCD (n = 63) and at r-DCD (n = 31). A third matched group of children with TD (n = 63) was formed. The MABC-2 checklist and the WASI tests were used as screening tools. Measures of executive function including verbal and nonverbal tasks for working memory, inhibitory control, and cognitive flexibility were tested. Multivariate analysis of variance followed by analyses of variance and Bonferroni tests were used to verify group effects on executive functions.
Results: A significant group effects were found for Working Memory, Λ = .78, F(4, 360) = 10.12, p ≤ .001, η _p ² = .12; Inhibitory Control, Λ = .59, F(16, 294) = 5.48, p ≤ .001, η _p ² = .23; and Cognitive Flexibility and Inhibitory Control, Λ = .60, F(22, 288) = 3.74, p ≤ .001, η _p ² = .22, with moderate effect sizes. The DCD group showed lower scores compared with the TD group on the visuospatial and verbal working memory; inhibitory control and in tasks of cognitive flexibility; the r-DCD group showed lower scores compared with the TD group for visuospatial working memory and for cognitive flexibility.
Conclusions and Implications: Poor performance in several measures of executive functions in children with DCD emphasized the need of motor/executive task-specific interventions. Furthermore, children at r-DCD showed low scores in several executive functions; therefore, preventive services should also be provided for this subclinical group.
(© 2019 John Wiley & Sons Ltd.)