Figure 1.

Comparison of published CO₂ production by doubly labeled water to that by standard method

(A) Relationship between CO₂ production (L/d) for 5,756 individuals extracted from the original studies and the recalculated estimates using Equation 1.

(B–D) Bland-Altman plots²⁵ comparing the published rCO₂ for studies using (B) the Coward and Prentice²² equation, (C) the Schoeller et al.¹⁵ A6 equation, and (D) the Racette et al.¹⁹ compared with the standard Equation 1 derived from Sagayama et al.²⁰ In all plots, dotted line is average difference, and solid blue lines are plus and minus 2 SDs. The red lines define the boundary for plus and minus 10% difference between methods. Data refer to 5,756 adult individuals uploaded into the IAEA DLW database (v3.1).