Normal growth and techniques of growth assessment

Abstract

The shape of the human growth curve is described and illustrated. Growth studies may be longitudinal, cross-sectional, mixed longitudinal or linked-longitudinal; each has advantages and disadvantages, and each requires appropriate statistical methods for handling the data. Standards for height and height velocity for use in a clinical setting wherein follow-up over several years is presumed are described and illustrated. Such standards have to take into account tempo of growth at ages over nine years. Cross-sectionally derived standards do not do this and are not suitable for clinical use. The techniques of measurement of height, sitting height and skinfolds are described and illustrated. Growth and development during puberty is described; there are changes in body composition as well as in body size and shape. Standards for pubertal stages of breasts, pubic hair and genitalia are given and emphasis is laid on the great variation in both the timing and the duration of these pubertal changes. Measurement of developmental age is discussed. The Greulich-Pyle and Tanner-Whitehouse methods for skeletal age are described. These methods can be used for predicting adult height which is useful both in diagnosis and in following the effects of treatment. In diagnosis the predicted adult height is compared to the range of expected heights in the children of the particular pair of parents concerned (the so-called 'target' range of heights) to see if smallness is simply due to delay. Change in Tanner-Whitehouse predicted height occurs on successful treatment of, for example, growth hormone deficient short stature, and is thus a guide to the success of treatment. Standards are also given for height of children from age two to nine inclusive, with allowance for height of their parents.