A comparison of objective measures of activity and distractibility in hyperactive and nonhyperactive children.

In a 15-minute free-play and a 5-minute test session, 13 measures of activity, distractibility, and parental ratings of activity were obtained on three groups of children, consisting of 16 boys referred to a psychological services center for evaluation of possible hyperactivity, 16 referred to that same center for problems other than hyperactivity, and 20 obtained from the local community. Subjects were boys with average intelligence between the ages of 4 and 12 years. Results indicated that the multiple measures of activity and distractibility had significant but relatively low order correlations among themselves. These relationships varied as a function of the subject group. However, there was no sonsistent relationship between the measures of activity and distractibility. The pattern of relationships obtained suggested that both activity level and distractibility are not homogeneous, unidimensional constructs. Results also indicated that boys referred for hyperactivity displayed greater wrist activity in free play, tended to display greater ankle activity in free play, had significantly correlated wrist and ankle activity, and were rated by their parents as more active than other children. This pattern suggested a global restlessness in children referred for hyperactivity that distinguishes them from other children.