Analysis of the ROC curve of the Weight-Waist Circumference Index (WWCI)

Abstract

The Weight-Waist Circumference Index (WWCI) was evaluated through Logistic Regression. A descriptive, prospective and cross-sectional study, in a sample of 1095 adults and older adults, age between 20 and 96 years. Methods: Variables were measured: age, weight, size, Waist Circumference (WC), Body Mass Index (BMI), Waist-Size Index (WSI) and Percentage of Body Fat (PBF).  Results: Similar BMI in both sexes; higher WC and WSI averages in a ≥ age of 65; Major WWCI in group 20-59 years; WWCI risk rate (54.1%) is higher than WC (44.7%) but less than WSI 78.2%). The WWCI is significantly associated with BMI, WC and WSI (p<0.000); positive predictive value 0.92 and negative predictive value 0.70; the PBF average is 30.2±9,7  in group 20 – 59  years and 40.0±7.8 in group ≥ 60 years; average higher PBF in women than  in men, and statistically significant (p<0.000); Relative Risk, 1.92; the Wald test statistic indicates statistical significance for the coefficients of the two risk probability equations; the area under the ROC curve is 0.803 and 0.903 (P<0.000), WWCI's high-capacity discriminatory signal; in addition to high sensitivity and specificity. Conclusion: The Weight-Waist Circumference Index (WWCI) can be considered as an indicator for assessing overweight and obesity in adults, as it has a can of discriminatory ability.