Cognitive and motor function in developmental coordination disorder.

Aim: To analyse the development of motor skill and executive function in school-aged children with and without developmental coordination disorder (DCD).
Method: Using a longitudinal design, 186 children (86 males, 100 females) aged 6 to 11 years at Time 1 were tested over a 2-year period, 52 of whom were diagnosed with DCD at Time 1 (27 males, 25 females; mean age 8y 5mo, SD 1y 6mo) using DSM-5 criteria. The McCarron Assessment of Neuromuscular Development assessed motor status at Time 1 and at 2-year follow-up (Time 2). Executive function was assessed using a well-validated measure, the Groton Maze Learning Test.
Results: The DCD cohort at Time 1 had moderate incidence of executive function deficit (41%). Most importantly, at a group level, children with persisting DCD (across Times 1 and 2) also showed significantly lower levels of executive function than children with typical motor development at both time points. At an individual level, around 26% of children in this group had persisting executive function deficits relative to normal ranges of performance.
Interpretation: Children with persisting DCD are at significant risk of executive function issues. The combination of motor and cognitive issues as a potential risk factor in the longer-term development of children is discussed.
What This Paper Adds: Around half of children initially diagnosed with developmental coordination disorder (DCD) had the same diagnosis at 2-year follow-up. 41% of children with DCD have impaired executive function. Children with persisting DCD show poorer executive function than those with typical motor development or remitting DCD.
(© 2020 Mac Keith Press.)