Motor characteristics in children with developmental coordination disorder and attentiondeficit/hyperactivity disorder: intergroup comparison and predictors.

BACKGROUND:Children with Attention-Deficit/Hyperactivity (ADHD) and/or Developmental Coordination Disorder (DCD) show high rates of motor difficulties in daily activities. This study aimed to examine the validity and reliability of the Developmental Coordination Disorder Questionnaire (DCDQ) in identifying motor characteristics in daily activities, differentiating children with ADHD-only, with DCD-only and with ADHD and DCD comorbidity. METHODS:Thirty-three children with ADHD-only, 30 with DCD-only, 33 with ADHD/DCD, and 35 controls participated to the study. Diagnosis satisfied DSM-5 criteria for ADHD and DCD. The DCDQ was administered to all children; moreover, the association between DCDQ scores and ADHD symptoms, measured by SNAP-IV, and motor coordination severity, measured by M-ABC subscales, was examined. RESULTS:The DCDQ subscale scores were significantly lower in all clinical groups than in controls, but only minimal differences were found between the clinical groups. Principal Component Analysis (PCA) of DCDQ identified five components showing the best adaptability and accounting for 71% of the variance. Both ADHD-only and ADHD/DCD achieved a better performance than DCD-only in the "Motor control in running/jumping". Conversely, children with DCD-only performed better in "General coordination". ADHD-only reached better mean scores than ADHD/DCD in "Motor control with the ball" and, than DCD, in "Planning". Inattention, hyperactivity-impulsivity at SNAP-IV, and balance at M-ABC, represented the main predictors for ADHD-only, ADHD/DCD and DCD-only, respectively. CONCLUSIONS:DCDQ may represent a useful measure to detect the different areas of difficulties in children with neurodevelopmental disorders and provides suggestions for identifying distinct altered processes underlying ADHD and DCD, alone or in comorbidity.