We think that the article by contains inaccurate and misleading information. The first important criticism is the title, which implies that longitudinal data on the clinical course of the disease are to be presented. This can only be measured by observation over a period of time, and no such data were shown in the paper. The second important criticism is that from the data given in the paper, it would not be possible to repeat the study. We are not told how height was measured (e.g., by tape measure, stadiometer, or anthropometer) or whether allowances were made for contractures or scoliosis in the older boys. Of the 111 boys evaluated, only 92 had their height measured. What happened to the remaining 19? The bald statement that height was corrected for age is not good enough in so potentially important an article: neither the manner of correction nor a reference justifying its use is given. The most unconvincing part of the paper is the claim to demonstrate a significant relationship between height and severity of dystrophy. There is, unsurprisingly, a correlation between age and Vignos scale and also between two age-dependant variables, height and weight, and Vignos scale. The correlation coefficient for age and severity is 0.761, which is not unexpected. If height were a major determinant of disease severity, one would expect that with age eliminated, the correlation coefficient for corrected height and disease severity would be greater rather than less. In fact, the coefficient was only 0.352, which is a very poor correlation. The fact that the P value is less than .05 simply shows that one can be 95% certain that the poor correlation is not a chance observation. Incidentally, we are pleased that the authors have