Parameter

Disease stage

Joint mixed model

Curvebycurve


 
Estimate

Std. error

Estimate

Std. error


τ
_{1}

II

84.15

10.14

82.42

18.15


III

74.97

8.43

82.28

24.35


IV

97.12

15.78

128.45

32.58

$\dot {\mathrm {V}}\mathrm {O}_{2}rest$

II

282.9

13.27

284.52

13.62


III

288.82

11.09

284.04

18.27


IV

266.79

19.25

283.08

24.44

$\dot {\mathrm {V}}\mathrm {O}_{2}ss$

II

1029.6

55.17

1007.7

58.46


III

948.53

46.14

940.83

78.43


IV

737.07

79.94

815.41

104.93

τ
_{2}

II

–3.77

0.28

–4.68

0.41


III

–2.91

0.23

–3.74

0.54

$\dot {\mathrm {V}}\mathrm {O}_{2}recovery$

II

276.03

7.51

301.3

18.8


III

242.53

9.8

276.03

25.22


IV

209.71

15.03

294.65

33.75

T
$_{1/2} \dot {\mathrm {V}}$
O_{2}

II

129.14

9.9

127.65

9.53


III

134.7

8.46

136.51

12.79


IV

178.82

15.27

161.6

17.11


τ
_{1}: growth rate of the monoexponential
$\dot {\mathrm {V}}$
O_{2} function during 6MWT;
$\dot {\mathrm {V}}\mathrm {O}_{2}rest$
,
$\dot {\mathrm {V}}\mathrm {O}_{2}ss$
and
$\dot {\mathrm {V}}\mathrm {O}_{2}recovery$
: oxygen level at rest, steady state during exercise and recovery, respectively; τ
_{2}: steepness of the exponential decay during the recovery phase;
$\mathrm {T}_{1/2}\dot {\mathrm {V}}\mathrm {O}_{2}$
: time for half decrease of the
$\dot {\mathrm {V}}$
O_{2} level in the recovery phase