Intraclass correlation coefficient (95% CI) of the slope and projected apnoea threshold between measurement 1 and measurement 2 for rebreathing (slope-R and pAT-R, respectively) and steady-state (slope-SS and pAT-SS, respectively), calculated in the two randomised groups

Slope-R0.90 (0.66–0.98)0.87 (0.56–0.97)
Slope-SS0.49 (−0.17–0.84)0.58 (−0.14–0.90)
pAT-R0.90 (0.64–0.97)0.85 (0.50–0.96)
pAT-SS−0.08 (−0.65–0.55)0.55 (−0.80–0.89)

The outcomes of slope-R and pAT-R were significant (p<0.05); the outcomes of slope-SS and pAT-SS were not significant (p>0.05).