Kinematic and kinetic characteristics of graphomotor skills in children with neurodevelopmental disorders: The impact of DCD, ADHD, and ASD traits

Interest in the development of handwriting skills has been increasing; however, there is no consensus on the handwriting abilities of children with developmental coordination disorder (DCD), attention-deficit/hyperactivity disorder (ADHD), and autism spectrum disorder (ASD), and the specific handwriting characteristics associated with each neurodevelopmental disorder remain unclear. This exploratory study examined the preliminary associations between graphomotor skills and neurodevelopmental traits in 17 children (aged 7–11 years) diagnosed with DCD, ADHD, or ASD. The evaluation included handwriting fluency assessments, kinematic/kinetic analyses, and assessments of neurodevelopmental disorder traits. The participants performed tracing tasks involving straight lines, sine waves, and triangular waves using the TraceCoder® system. Graphomotor kinematic/kinetic parameters, including deviation from the baseline, pen pressure, velocity, acceleration, jerk, and area, were quantified. Fluency was assessed using the Understanding Reading and Writing Skills of Schoolchildren II test. Neurodevelopmental traits were evaluated using the DCD Questionnaire, ADHD Rating Scale, and Autism Spectrum Quotient. Increased DCD, ADHD and ASD traits were correlated with deteriorations in graphomotor parameters, such as greater deviation, and increased acceleration, jerk, and pen pressure. In contrast, higher ASD traits were associated with improvements in handwriting fluency. These preliminary findings suggest that graphomotor characteristics may vary depending on specific neurodevelopmental traits, underscoring the potential value of tailored assessments and interventions.