Impact of skewing in body weight upon body mass index statistics in a male model population

Abstract

There is insufficient research concerning whether an increase in skewness of the variable body weight W would influence body mass index (BMI) statistics, and hence falsify conclusions. In this study, a model male population was generated. Dividing W by a normally distributed variable produced its skewing to the right. Apart from expected changes in the means, standard deviations, and other statistics of W and BMI, the results revealed that Benn’s index and the correlation r_HBMI remained unchanged over a large range of distribution asymmetry. Counts of elements that would fall into the overweight category, decreased in favour of the obesity class – an intuitively unexpected result. A verifiable rise in skewness resulted in loss of the normal distribution assumption for W and BMI.