The subtypes of developmental coordination disorder.

Area of Science:

• Developmental psychology
• Neuroscience
• Pediatrics

Background:

• Developmental Coordination Disorder (DCD) is a neurodevelopmental condition affecting motor skills.
• DCD is recognized as a heterogeneous condition with varying presentations.
• Understanding subtypes of DCD is crucial for targeted interventions.

Purpose of the Study:

• To identify distinct subtypes within a large cohort of children diagnosed with DCD.
• To analyze patterns of motor, cognitive, and visual-motor abilities to differentiate subtypes.
• To characterize the identified subtypes based on specific skill deficits.

Main Methods:

• Utilized standardized scores from assessments including IQ tests, Movement Assessment Battery for Children (MABC-2), and Beery-Buktenica Developmental Tests (Beery-VMI, Beery-MC, Beery-VP).
• Employed the NbClust procedure for data partitioning to identify clusters among 98 children.
• Applied deviation contrasts, MANOVA, and post hoc tests for cluster characterization.

Main Results:

• Identified four distinct clusters (subtypes) of DCD.
• Two clusters exhibited broad motor skill deficits, with variations in visual-motor integration and specific motor skills.
• One cluster showed specific gross-motor problems, and another presented with preserved ball skills but lower motor coordination and IQ scores.
• Balance scores were consistently identified as 'at risk' or 'abnormal' across all four identified subtypes.

Conclusions:

• DCD is a heterogeneous disorder, but distinct subtypes can be identified based on motor, cognitive, and visual-motor profiles.
• Approximately half of the children demonstrated generalized motor impairments.
• A significant finding is the presence of a generalized balance problem across all identified DCD subtypes, irrespective of their specific skill deficits.