Table 2 Model input parameters

Costs ($)

Sintilimab (100 mg)

149.38

119.50-179.26

Gamma

Local estimate

Cisplatin (100 mg)

17.15

13.72–20.58

Gamma

Local estimate

Paclitaxel (100 mg)

90.03

72.02-108.04

Gamma

Local estimate

5-fluorouracil (100 mg)

3.49

2.79–4.19

Gamma

Local estimate

Routine follow-up cost per cycle

73.57

58.86–88.28

Gamma

[1]

Cost of laboratory tests and radiological examinations

356.60

285.28-427.92

Gamma

[1]

Cost of supportive care per cycle

167.29

133.83-200.75

Gamma

[1]

Costs of serious adverse events ($)

decrease in neutrophil count

454.26

363.41-545.11

Gamma

[7]

decrease in white blood cell count

466.00

372.8-559.2

Gamma

[1]

Anaemia

508.2

406.56-609.84

Gamma

[1]

Nausea

71.00

56.8–85.2

Gamma

[8]

Vomiting

71.00

56.8–85.2

Gamma

[8]

Risks of serious adverse events in Sintilimab group (> grade 3) %

decrease in neutrophil count

30

2.4–3.6

Beta

[9]

decrease in white blood cell count

17

13.6–20.4

Beta

[9]

Anaemia

13

10.4–15.6

Beta

[9]

Nausea

2

1.6–2.4

Beta

[9]

Vomiting

2

1.6–2.4

Beta

[9]

Risks of serious adverse events in placebo group (> grade 3) %

decrease in neutrophil count

34

27.2–40.8

Beta

[9]

decrease in white blood cell count

22

17.6–26.4

Beta

[9]

Anaemia

10

8–12

Beta

[9]

Nausea

2

1.6–2.4

Beta

[9]

Vomiting

2

1.6–2.4

Beta

[9]

Utility value

PFS

0.68

0.54–0.82

Beta

[2]

PD

0.42

0.34–0.50

Beta

[2]

decrease in neutrophil count

-0.20

-0.16–0.24

Beta

[6]

decrease in white blood cell count

-0.090

-0.072 - -0.11

Beta

[10]

Anaemia

-0.074

-0.059 - -0.089

Beta

[10]

Nausea

-0.13

-0.104–0.156

Beta

[6]

Vomiting

-0.13

-0.104–0.156

Beta

[6]

Discount rate %

5

4–6

Beta

[11]