. (1970), Archives of Disease in Childhood, 45, 13. Variations in the pattern of pubertal changes in boys. Mixed longitudinal data on the physical changes at puberty in 228 normal boys are presented together with normal standards for stages of genital and pubic hair development.The genitalia began to develop between the ages 91 years and 131 years in 95% of boys (mean = 11 -6 ± 0 09) and reached maturity at ages varying between 13 and 17 (mean = 14-9 ± 1 10). The age at which pubic hair first appeared was not accurately determined, but its development through the later stages was studied. It reached the equivalent of an adult female distribution at a mean age of 15'2 ± 0-01 years.On average the genitalia reached the adult stage 3 * 0 years after they first began to develop; but some boys completed this development in as little as 1 * 8 years while others took as much as 4 * 7 years. Some boys complete the whole process in less time than others take to go from Stage G2 to Stage G3. The genitalia begin to develop before pubic hair is visible in photographs in practically all boys.The 41 boys in whom it could be studied reached their maximum rate of growth (peak height velocity) at a mean age of 14i 1 ± 0 14 years.Very few boys (about 5 %) reached peak height velocity before their genitalia were in Stage 4 and over 20% did not do so until their genitalia were adult. Peak height velocity is reached, on the average, nearly 2 years later in boys than in girls, but the boys' genitalia begin to develop only about 6 months later than the girls' breasts. Pubic hair appears about 14 years later in boys than in girls.In a recent paper we described variations in the ages at which girls reached different stages of puberty and in the rates at which they passed from one stage of development to the next (Marshall and Tanner, 1969). We discussed also the degree to which progress in one event of puberty, for example breast development, could normally be out of step with another, such as growth of pubic hair. We now report a similar study of the maturation of boys.The ages at which Dutch boys reached various stages of genital and pubic hair development in 1965 were estimated in a large cross-sectional study by Van Wieringen et al. (1968), but there are no comparable recent data from other parts of Europe. In any case, cross-sectional data cannot tell us how much individuals vary in the rate at which they pass through puberty nor how the
. (1975). Archives of Disease in Childhood, 50, 14. Prediction of adult height from height, bone age, and occurrence of menarche, at ages 4 to 16 with allowance for midparent height. Multiple regression equations for predicting the adult height of boys and girls from height and bone age at ages 4 and upwards are presented. There is a separate equation for each half year of chronological age; and for pre-and postmenarcheal girls at ages 11 to 14. These are based on longitudinal data from 116 boys and 95 girls of the Harpenden Growth Study and the London group of the International Children's Centre longitudinal study.The bone age used is the revised version of the Tanner-Whitehouse stardards, omitting the score for carpal bones (RUS age, TW 2 system).Boys aged 4 to 12 are predicted in 9500 of instances to within ±7 cm of true height, and at ages 13 and 14 to within ±6 cm. Girls aged 4 to 11 are predicted to within ±6 cm; premenarcheal girls aged 12 and 13 to within ±5 and ±4 cm, respectively; and postmenarcheal girls aged 12 and 13 to within ±4 and ±3 cm, respectively. Prediction can be somewhat improved by allowing for midparent height. One-third of the amount that midparent height differs from mean midparent height is added or subtracted.An alternative system of equations which are based on initial classification by bone age rather than chronological age is given. These have about the same accuracy as the equations based on initial classification by chronological age, but allowance for bone age retardation is less. It is not clear which system is preferable.The equations probably apply to girls complaining of tall stature and boys or girls complaining of shortness and needing reassurance as to normality. In clearly pathological children, such as those with endocrinopathies, they do not apply.
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