Prevalence of Hyperkinesis

Abstract

Three rating scales with different items and modes of rating were used to assess the prevalence of hyperactivity among 1,908 children in 7 primary (elementary) schools. Teachers rated all the children in their classes. The number of children found to be hyperactive according to Conners rating scale was 5.6 percent using a cut-off of 2 standard deviations above the mean, or 12 percent using the American cut--off of 15. The Queensland rating scale gave a hyperactivity rate of 7.5 percent, and the Pittsburg scale a rate of 8.9 percent. The overlap of the rating scales gave 3.5 percent and the sum of those identified was 12 percent. More children were found to be hyperactive in lower socio--economic areas. Variation in the children thought to be hyperactive presents a problem for research, but the impact of difficult children in the classroom must not be underestimated.