Is TW3 height prediction more accurate than TW2? Preliminary data

Skeletal maturation is considered a reliable variable in evaluating the 'tempo' of growth. It is important in the diagnosis of endocrinological diseases, in chronic diseases, in hormonal therapy follow-up and in computing height prediction for prognostic and therapeutic purposes. It is also used when chronological age is not available for minors without known birth dates. There are different methods to evaluate skeletal maturation and height prediction. The Tanner-Whitehouse (TW) method 2 (TW2) has been considered to be the most useful method so far, and has recently been updated with modified height prediction equations (TW2-Mark II). TW3 is the newest method. The aim of this study is to evaluate whether TW3 is more accurate in the assessment of height prediction than TW2-Mark II in a sample of healthy north Italian subjects.

Anthropometrical data were collected as part of a survey in 1977-1978 in Turin. The sample involved 1,384 healthy children. The children, now adults, have been traced and recalled to measure their final height in order to test height prediction reliability. At present, we have collected 118 adult heights.

According to the TW2 method 40% of the males had a height prediction error larger than +/- residual SD (4.1 cm), and with TW3 this was 32.9%. The female height prediction error with TW2 was larger than +/- residual SD (3.6 cm) in 29.2% of girls, and the same value was found with TW3.

According to our preliminary data, TW3 does not represent any real progress.