Body Adiposity Index
Encyclopedia
The Body Adiposity Index (BAI) is a method of measuring human body fat. Unlike the body mass index
(BMI) usually used as a proxy for body fat, the BAI is calculated without using body weight. It is stated by its definers that, based on population studies, the BAI is numerically approximately equal to the percentage of body fat for adult men and women of differing ethnicities.
The BAI is calculated as:
BAI = (hip circumference in centimetres) / (height in metres)1.5 − 18
Hip circumference (R = 0.602) and height (R = −0.524) are strongly correlated
with percentage of body fat. Comparing BAI with "gold standard
" dual-energy X-ray absorptiometry (DXA) results, the correlation between DXA-derived percentage of adiposity and the BAI in a target population was R = 0.85, with a concordance
of C_b = 0.95.
Stated advantages of the BAI are that it approximates body fat percentage, while the widely used BMI is known to be of limited accuracy, and is different for males and females with similar percentage body adiposity; and that it does not involve weighing, so can be used in remote locations with limited access to scales.
Body mass index
The body mass index , or Quetelet index, is a heuristic proxy for human body fat based on an individual's weight and height. BMI does not actually measure the percentage of body fat. It was invented between 1830 and 1850 by the Belgian polymath Adolphe Quetelet during the course of developing...
(BMI) usually used as a proxy for body fat, the BAI is calculated without using body weight. It is stated by its definers that, based on population studies, the BAI is numerically approximately equal to the percentage of body fat for adult men and women of differing ethnicities.
The BAI is calculated as:
BAI = (hip circumference in centimetres) / (height in metres)1.5 − 18
Hip circumference (R = 0.602) and height (R = −0.524) are strongly correlated
Pearson product-moment correlation coefficient
In statistics, the Pearson product-moment correlation coefficient is a measure of the correlation between two variables X and Y, giving a value between +1 and −1 inclusive...
with percentage of body fat. Comparing BAI with "gold standard
Gold standard (test)
In medicine and statistics, gold standard test refers to a diagnostic test or benchmark that is the best available under reasonable conditions. It does not have to be necessarily the best possible test for the condition in absolute terms...
" dual-energy X-ray absorptiometry (DXA) results, the correlation between DXA-derived percentage of adiposity and the BAI in a target population was R = 0.85, with a concordance
Concordance correlation coefficient
In statistics, the concordance correlation coefficient measures the agreement between two variables, e.g., to evaluate reproducibility or for inter-rater reliability.-Definition:...
of C_b = 0.95.
Stated advantages of the BAI are that it approximates body fat percentage, while the widely used BMI is known to be of limited accuracy, and is different for males and females with similar percentage body adiposity; and that it does not involve weighing, so can be used in remote locations with limited access to scales.