Fig. 1
Observed values of the V̇O2VAT (graph A), V̇O2peak (graph B), and V̇E/V̇CO2-slope (graph C) in each patient using the self-preferred approach ordered according to increasing value of the mean. Dots represent values determined by individual observers. Each vertical collection of dots represents an individual patient, in which each patient has a unique color throughout all graphs. Horizontal dotted lines represent known risk assessment thresholds defined as 11.1 mL/kg/min for V̇O2VAT [4] (graph A) and 18.2 mL/kg/min for V̇O2peak [4] (graph B). Error bars represent the SD of the mean. Abbreviations: SD = standard deviation; V̇E/V̇CO2-slope = slope of the relationship between the minute ventilation and carbon dioxide production; V̇O2peak = oxygen uptake at peak exercise; V̇O2VAT = oxygen uptake at the ventilatory anaerobic threshold