Smoothed frequency distribution of body mass index and waist circumference for men and women from the two surveys. The population percentage, on the y-axis, is plotted against BMI (Figure 1. A-
B) or WC (Figure 1. C-
D), on the x-axis. Curve fitting and loess smoothing were performed using Matalab2007a. The median figures are presented. The differences between the two surveys were tested with the Mann–Whitney U-test.