Subtypes in developmental coordination disorder: what do we know so far? A systematic review

Developmental coordination disorder (DCD) is a highly heterogeneous disorder. This systematic review examined whether statistically derived clusters can effectively distinguish subgroups of children with DCD. Web of Science, Scopus, PubMed, Embase, and PsycInfo were systematically searched (CRD420251237685) using controlled terminology and free-text terms. Studies were eligible if they included children (aged 0-18 years) with DCD with(out) comorbidities and employed statistical clustering to identify subtypes. Methodological quality was assessed using an adapted version of the Critical Appraisal Skills Programme and certainty of the evidence with the Grading of Recommendations Assessment, Development and Evaluation. Ten of the 1719 search results were included, three of which included both children with DCD and typical development. Two studies explored clusters unidimensionally (motor-only and mental health-only). Eight studies included multiple domains of functioning: motor (n = 8), sensory functions (n = 5), fitness (n = 3), cognitive functions (n = 3), executive functions (n = 2), mental health (n = 1), and participation (n = 1). Studies identified between four (n = 4) and six (n = 1) subtypes, which primarily reflected gradients of severity rather than distinct domain-specific profiles. The overall certainty of evidence for distinct subtypes in DCD was rated low to very low.

Evidence suggests that DCD is better conceptualized as a spectrum of pervasiveness rather than discrete subtypes. Existing findings lack consistency across studies due to methodological shortcomings and variable measurement domains. Although evidence-based clinical subtypes cannot yet be recommended, future research should prioritize subtyping studies focused on primary symptoms to better identify potential phenotypes within the DCD population.

• DCD is a heterogeneous condition, and identifying discrete subtypes is a long-standing research goal to improve clinical support. • Researchers have proposed various motor and non-motor profiles, but no consensus exists on a definitive subtyping model.

• This review found no consistent discrete subtypes, suggesting DCD is better viewed as a spectrum of pervasiveness rather than categories. • Future research should focus on subtyping primary motor symptoms to determine whether distinct, stable subgroups exist within the broader DCD population.