High motor variability is an often-found characteristic of Developmental Coordination
Disorder (DCD). Still, the role of high motor variability in DCD needs further examination.
This study focused on variability in coordination patterns, which is essential considering
that DCD is a coordination disorder. We examined variability in coordination patterns
of the arm over repetitions of trials in goal-directed reaching movements. This variability
was partitioned into variability that does not affect the index fingertip position
(V-ucm) and variability that does affect the index fingertip position (V-ort). This
study aimed to increase the understanding of motor variability in DCD by comparing
V-ucm and V-ort on between children with DCD and typically developing (TD) children
in a goal-directed reaching task. Twenty-two children (eleven with DCD) ages 6-11
performed 30 reaching movements. The Uncontrolled Manifold method was used to quantify
V-ucm and V-ort. Results showed that children with DCD had more V-ucm than TD children
while V-ort was similar between groups, showing that coordination patterns in children
with DCD are more variable, but interestingly, this higher variability does not affect
performance. This study indicates that high motor variability in DCD is not necessarily
negative. Possible roles of motor variability in DCD are discussed.