Figure 2.

Comparison of in-clinic performance of silver standard protocols relative to the gold standard for (A) 12-minute run test (12-MRT) and (B) 3-minute step test. For each plot, we are showing the difference between the ground truth maximal oxygen consumption measurement and measurements obtained using the distance run around a track (for A) and heart rate via radial pulse measured by trained research staff (for B) as per Tecumseh protocol. This distance was also measured using GPS and heart rate was measured using a chest strap and Fitbit. The concordance between distance measured around the track and measured using the GPS in the phone was 0.96. (C) to (F) show the concordance of the 12-MRT test for different values of self-reported effort. VO₂max: maximal oxygen consumption.