Comparative Adiposity Study of a Body Shape Index and Body Adiposity Index with BMI using DEXA as Gold Standard

Medcalc software. Results: Correlation studies revealed gender (r -0.727, P <0.001, CI -0.847 to -0.537), BMI (r 0.76, P <0.001, CI 0.592 to 0.868), BAI (r 0.69, P <0.001, CI 0.482 to 0.824), ABSI (r -0.37, P 0.019, CI -0.611 to -0.066) and region fat percentile (r 0.99, P <0.001, CI 0.99 to 0.99) as significantly correlated with DEXA tissue fat percentile. A strong positive correlation was also observed between DEXA tissue percentile and measurements like BMI, BAI and region fat percentile, whereas the correlation with ABSI was moderate inverse. Insignificant correlation was attained with variables like age and bone mineral content. However, the inter-rater agreement statistics performed on classified variables showed that BMI possessed significant moderate agreement (K = 0.54) and BAI had poor agreement (K = 0.14) with DEXA tissue fat percentile. Additionally, mountain plot analysis revealed a positive bias of 9.35 between BMI and DEXA tissue fat (%) (limits of agreement -5.89 to 25.72), and a bias of 4.44 for BAI, with more variability (limits of agreement between -13.58 and 22.48) compared to BMI. Conclusion: From the current study we can conclude that, BMI, BAI and ABSI underestimate the body adiposity when compared to DEXA tissue fat %. Additionally, BAI also exhibited a poor agreement with reference when assessed as a classified measure, compared to BMI.