Does subtype of developmental coordination disorder count: is there a differential effect on outcome following intervention?

It is well known that developmental coordination disorder (DCD) is a heterogeneous condition in which children frequently present with co-occurring conditions in addition to their motor difficulties. This study considered whether there would be a differential effect of a group treatment program on subtypes of perceptual and movement problems or associated co-occurring conditions. A subset of children (n=43) from a larger clinical sample (n=100) with DCD participated in a 214 year cross-over intervention study which followed the cognitive orientation to daily occupational performance (CO-OP) approach. Original subtypes were determined by contrasting the current sample with previously published subtyping studies in DCD [Hoare, D. (1994). Subtypes of developmental coordination disorder. Adapted Physical Activity Quarterly, 11, 158-169; Macnab, J. J., Miller, L. T., & Polatajko, H. J. (2001). The search for subtypes of DCD: Is cluster analysis the answer? Human Movement Science, 20, 49-72]. No advantage was conferred to any subtype although children with more profound and complex difficulties at initial assessment, despite progress following intervention, were most likely to have continuing difficulties at the end of the project.