The calculation is from the formula of DuBois and DuBois:
= (W 0.425 x H 0.725) x 0.007184
the weight is in kilograms and the height is in centimeters.
DuBois D, DuBois EF. A formula to estimate the approximate
surface area if height and weight be known. Arch Intern
Medicine. 1916; 17:863-71.
Wang Y, Moss J, Thisted R. Predictors of body surface area.J Clin Anesth.