Body fat percentage (BF%) is easily measured by skinfold calipers. It can be mea
ID: 3171736 • Letter: B
Question
Body fat percentage (BF%) is easily measured by skinfold calipers. It can be measured much more reliably by Dual Energy X-Ray Absorptiometry (DEXA). Body Mass Index (BMI) and waist-to-hip ratio (WH ratio) are two other measures of body composition commonly used in health assessment.
Use the following health data, which was collected from 7 college students, to establish the concurrent validity of WH ratio as a measure of body composition.
What is the correlation coefficient associated with the criterion validity of WH ratio with respect to BF% as measured by DEXA? (Answer to three decimal places)
Subject BF%DEXA BF%
skinfold BMI WH ratio 1 14.4 14.1 24.0 0.96 2 18.7 25.9 26.4 1.05 3 11.7 15.2 19.5 0.74 4 18.2 23.4 28.9 1.01 5 12.4 13.4 19.7 1.03 6 21.3 22.9 31 1.05 7 28.7 35.2 38.2 1.09
Explanation / Answer
So the correlation coefficient is 0.666
BF% DEXA WH Ratio 14.4 0.96 18.7 1.05 11.7 0.74 18.2 1.01 12.4 1.03 21.3 1.05 28.7 1.09 r= 0.666018