Abstract
Anthropometric data were collected on groups of seven-year-old Dunedin (New Zealand) boys, identified as hyperactive-only, aggressive-hyperactive, aggressive-only and non-aggressive/non-hyperactive. Measures taken included stature, weight, skeletal maturity, mid-upper arm circumference, triceps and subscapular fatfolds and body-mass index. The hypothesis that hyperactive-only boys would show delayed maturation, as indicated by lower bone-age, was not confirmed. However, these boys had significantly smaller mid-upper arm circumference, triceps fatfold and body-mass index than the other groups. The results suggest that body leanness may discriminate 'pure' hyperactive boys from aggressive-hyperactive boys.