(P15-031-24) Expert Consultation to Inform a Diagnostic Test Accuracy Systematic Review for Tests Assessing Excess Adiposity in Children and Adolescents for the Diagnosis of Obesity

Objectives: To convene worldwide experts to discuss methods of assessing excess adiposity to facilitate the diagnosis of infants, children, and adolescents with obesity in all their diversity.

Methods: A key decision in a Diagnostic Test Accuracy (DTA) systematic review is selecting the reference standard(s) to compare the accuracy of the index test(s) of interest (i.e. BMI for age and sex) to acceptable clinical assessments to diagnose the target condition (excess adiposity). Written and virtual feedback was solicited from 40 global experts in childhood obesity and body composition about the best available tests or combinations of tests to measure body composition and determine excess adiposity among infants, children, and adolescents as well as currently used cutoffs and types of adiposity for determining obesity for each age group.

Results: Deuterium oxide dilution, MRI, DXA, air displacement plethysmography, hydrostatic weighing, and multicompartmental models were identified as acceptable reference standards, with the 4-compartmental model most preferred. Experts questioned whether DXA is superior or conventional due to relatively lower cost, resources, and training. Waist circumference and BIA were preferred tests to use either alone or in combination with BMI for age and sex in diagnosing obesity; preferential use was country specific. Most experts preferred fat mass index to % body fat, as the equation is more sensitive to changes over time and depends on age and height as BMI does. Most experts agreed that total and regional adiposity are important for determining metabolic risk, but central adiposity for diagnosing obesity is country specific due to variations in body type. All agreed that age, race, ethnicity, and maturity stage should be considered to determine thresholds or cutoffs for excess adiposity for diagnosing obesity.

Conclusions: Feedback from experts highlighted challenges in selecting a reference standard for a DTA systematic review of BMI for determining excess adiposity in infants, children, and adolescents.

Funding Sources: Texas A&M Agriculture, Food, and Nutrition Evidence Center.

The authors are responsible for the views herein expressed and they do not necessarily represent the views, decisions, or policies of the institutions with which they are affiliated.