Assessment of the validity of multiple obesity indices compared with obesity-related co-morbidities

Abstract

Objective: The aim of the present study was to compare selected obesity indicators with comprehensive health status. Design: The study employed a pooled cross-sectional design. Setting: BMI, waist circumference, waist-to-height ratio (WHtR) and body fat percentage were considered as indirect obesity indicators. The Edmonton Obesity Staging System (EOSS) was used as a composite indicator to comprehensively reflect obesity-related co-morbidities. Cohen's κ coefficient was used to evaluate inter-measurement agreement for obesity. Conformity of indirect obesity indicators to the EOSS was assessed based on percentage agreement (proportion classified as obese and severely unhealthy as a result of obesity among the total sample), sensitivity (proportion classified as obese among individuals severely unhealthy as a result of obesity) and specificity (proportion classified as non-obese among fairly healthy individuals). Logistic regression analysis was used to identify the sociodemographic factors most strongly associated with conformity. Participants: The study included 17338 adults from the Korea National Health and Nutrition Examination survey conducted between July 2008 and May 2011. Results: Level of conformity to the EOSS was highest for WHtR (60.77 %) and lowest for BMI (35.96 %). WHtR and BMI had the highest sensitivity (53.7 %) and specificity (98.4 %), respectively. Predictability of conformity was lower among men for all indirect obesity indicators. Conclusions: WHtR has the greatest potential to identify individuals at risk of health problems due to obesity. Individual demographic factors must be considered in selecting the most appropriate obesity measurement.