Measurements on children under 13 years of age. Most of the data was collected from physical examinations in schools. The main variable of interest is the level of insulin-like growth factor (igƒ) (J. Clin. Endocrinol. Metab. 78(3): 744–752, March 1994). Each row in the data set corresponds to one individual. See also the dataset Igf, which includes adults.