Differentiation between attention-deficit/hyperactivity disorder and pervasive developmental disorders with hyperactivity on objective activity levels using actigraphs

To clarify differences in objective activity levels between children with attention-deficit/hyperactivity disorder (ADHD) and those with pervasive developmental disorders (PDD) and hyperactivity. Method: Eighteen boys with combined type ADHD, 10 boys with PDD with hyperactivity, and 18 control boys wore actigraphs for 1 week while attending elementary school. In addition to the average activity level, the standard deviation in the activity levels were compared for two continuous situations: (i) in-seat classes, in which the participants were expected to sit in their own seats and learn quietly; and (ii) free recess periods following the in-seat classes. Results: All the groups were affected by the situational shift, the average activity level of each the groups was higher and the standard deviation was smaller than those during the in-seat classes. The boys with ADHD exhibited a still smaller standard deviation than the controls and the boys with PDD and hyperactivity during the free recess period; no difference between the controls and the boys with PDD was seen. The boys with PDD exhibited a significantly lower average activity level than the other groups. No differences among the groups in the average activity levels and standard deviation were seen during the in-seat classes. Conclusions: The observed objective activity levels in each group reflect the degree to which the boys are able to tolerate changes in situations. Objective measurement of activity levels may be useful to differentiate hyperactivity in children with ADHD from that in children without ADHD.