Body Shape Index (BSI) is a metric for assessing the health implications of a given human body height, mass and waist circumference. The inclusion of the latter is believed to make the BSI a better indicator of the health risks from excess weight than the standard Body Mass Index.
According to the original article the formula for calculating aBSI is :
Here WC (Waist circumference) and Height are measured in meters.
The finding of the paper is that the BSI above 0.083 (when expressed in metric units) is indicative of a higher relative hazard. A value of 0.091 corresponds to the doubling of the relative hazard rate.