Quantitative Analysis of Movements in Children with Attention-Deficit Hyperactivity Disorder Using a Smart Watch at School

Attention-deficit hyperactivity disorder (ADHD) is primarily diagnosed using set criteria and checklists. However, authors have indicated that such criteria and checklists are subjective. In this study, data from the gyroscope and accelerometer in a smart watch were used to analyze the movements of children with ADHD. This study cohort comprised 15 children with ADHD and 15 age- and sex-matched control participants. The children with ADHD and controls wore the watches on their non-writing hands simultaneously in class. The recordings of one patient and one control were tracked for 2 h daily for three consecutive days with desk and seated class activities. We compared the measurements of variance and the zero-crossing rate (ZCR) of the gyroscope and accelerometer between the children with ADHD and controls. All average variance and ZCR values of the three axes (x,y, andz) in the gyroscope and accelerometer were higher in children with ADHD than in the controls. Significant differences in average variance values on they-axis (p< 0.001) and ZCR values on all three axes (x,p= 0.005;y,p= 0.003; andz,p= 0.004) of the gyroscope were observed. Similarly, significant differences in the average variance values on the three axes (x,p= 0.001;y,p< 0.001; andz,p< 0.001) and ZCR values on thez-axis (p= 0.006) of the accelerometer were observed. The proposed method is a promising tool to objectively analyze the movements of children with ADHD at school.