Table 3 Coefficient of variation throughout study in all spirometry blows and in those validated

Within subject coefficient of variation:

All spirometry attempts included

16.77%

(± 12.2)

10.20%

(± 10.55)

11.33%

(± 13.53)

Within subject coefficient of variation: Only spirometry attempts classed as usable or acceptable included

9.10%

(± 6.24)

8.15%

(± 8.18)

7.44%

(± 11.24)