Growth of schoolchildren with early, average and late ages of peak height velocity.

A sample of Swedish urban schoolchildren (357 girls, 373 boys) born in 1954/55 followed from 10 to 18 years were grouped according to peak height velocity age (PHV age) into early, average and late maturers. Mean heights differed between the maturity groups at ages from 10.0 to 14.0 years for girls and 10.5 to 17.0 years for boys. Mean weights differed between the maturity groups at all ages up to 16.0 years for girls and up to 18.0 years for boys. The earlier the maturity process, the heavier for given height. The time differences between peak weight velocity (PWV) and PHV significantly differed between early, average and late maturers amounting to 0.9, 0.5 and 0.2 years respectively for girls and 0.6, 0.3 and -0.1 years respectively for boys. The time difference between menarche and PWV did not differ between the maturity groups and amounted to about 0.6 +/- 0.05 years (SD = 0.9). For boys a similar lack of difference between maturity groups was obtained concerning the time difference between secondary sex characteristics; stage 4 (SSC IV) and PWV. Mean height and weight for girls and boys differed between the maturity groups at PHV but not at PWV, menarche or SCC IV.