Table 3 QALY calculation – separated by preoperative WOMAC score

0-20

14

47.50

21.68

74.86

16.49

27.36

23.26

16.48

7.95

7,043

1,813

8,421

1,778

4.10

3.25

3.38

2,055

2,313

21-40

75

50.09

22.85

71.99

22.07

21.89

27.63

16.71

8.68

6,698

1,860

8,100

2,304

4.46

6.93

2.73

1,816

2,737

41-60

110

59.19

17.86

78.10

19.95

18.91

22.82

17.16

7.9

6,198

1,036

7,582

1,843

3.25

4.88

2.41

2,332

2,892

61-80

77

68.09

16.48

83.31

12.44

15.22

20.35

18.58

7.16

6,034

978

7,487

1,419

2.79

3.99

2.05

2,684

3,310

81-100

16

79.69

16.23

86.63

10.79

6.94

17.55

20.39

7.61

5,948

617

7,568

1,118

2.27

4.73

1.00

3,337

6,757

Sum

292

59.76

20.72

78.22

18.78

18.45

23.55

17.57

7.92

6,310

1,341

7,730

1,854

3.43

5.23

2.39

2,256

2,964

UK preference-weighted index as underlying value set (QALY)

WOMAC pre-operative

N

Mean EQ-5D utility score pre-operative

SD

Mean EQ-5D utility score post-operative

SD

Mean change EQ-5D utility score

SD

Life expectancy

SD

Mean costs in €

SD

Mean costs incl. potential revision

SD

QALY

SD

QALY disc. 3.5%

Cost/QALY in €

Cost/QALY disc. 3.5%

0-20

14

0.04

0.12

0.81

0.17

0.77

0.16

16.48

7.95

7,043

1,813

8,421

1,778

12.40

6.17

9.50

679

823

21-40

75

0.30

0.31

0.76

0.25

0.46

0.33

16.71

8.68

6,698

1,860

8,100

2,304

8.20

8.78

5.76

987

1,300

41-60

110

0.54

0.25

0.86

0.15

0.31

0.28

17.16

7.90

6,198

1,036

7,582

1,843

5.85

6.77

3.98

1,295

1,751

61-80

77

0.70

0.17

0.88

0.16

0.18

0.24

18.58

7.16

6,034

978

7,487

1,419

3.28

4.64

2.40

2,281

2,829

81-100

16

0.80

0.06

0.94

0.10

0.14

0.14

20.39

7.61

5,948

617

7,568

1,118

3.16

2.81

2.03

2,393

3,329

Sum

292

0.51

0.30

0.84

0.19

0.33

0.31

17.57

7.92

6,310

1,341

7,730

1,854

5.95

7.08

4.25

1,300

1,669

German experience-weighted index as underlying value set (EB-QALY)

WOMAC pre-operative

N

Mean EQ-5D utility score pre-operative

SD

Mean EQ-5D utility score post-operative

SD

Mean change EQ-5D utility score

SD

Life expectancy

SD

Mean costs in €

SD

Mean costs incl. potential revision

SD

EB-QALY

SD

EB-QALY disc. 3.5%

Cost/EB-QALY in €

Cost/EB-QALY disc. 3.5%

0-20

14

0.34

0.06

0.72

0.17

0.39

0.15

16.48

7.95

7,043

1,813

8,421

1,778

6.49

4.60

4.76

1,297

1,643

21-40

75

0.44

0.13

0.71

0.18

0.27

0.18

16.71

8.68

6,698

1,860

8,100

2,304

4.71

5.09

3.39

1,721

2,207

41-60

110

0.53

0.12

0.77

0.14

0.24

0.17

17.16

7.90

6,198

1,036

7,582

1,843

4.39

4.17

3.04

1,726

2,292

61-80

77

0.65

0.12

0.80

0.12

0.15

0.17

18.58

7.16

6,034

978

7,487

1,419

2.79

3.62

2.02

2,685

3,368

81-100

16

0.73

0.08

0.86

0.06

0.12

0.11

20.39

7.61

5,948

617

7,568

1,118

2.59

2.20

1.75

2,920

3,856

Sum

292

0.54

0.16

0.76

0.15

0.22

0.18

17.57

7.92

6,310

1,341

7,730

1,854

4.05

4.32

2.90

1,908

2,439