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Table 2 Key model parameter distributions

From: Cost-effectiveness of introducing national seasonal influenza vaccination for adults aged 60 years and above in mainland China: a modelling analysis

ParameterMean (range/standard deviation)*Distribution
Proportion of high-risk groupsAdditional file 4: Fig. S3Beta
Flu-related ILI consultation rate [28]Additional file 5: Table S2Normal
Flu-related SARI hospitalization (per 100,000) [9]
 Beijing (2013–2014)105 (95%CI 85–129)Normal with μ = 105, sd = 11.22
 Beijing (2014–2015)66 (95%CI 50–86)Normal with μ = 66, sd = 9.18
 Jingzhou, Hubei province (2011–2012)89 (95%CI 85–90)Uniform (min = 85/100,000, max = 90/100,000)
Flu-related respiratory excess mortality [12]Additional file 5: Table S2Lognormal
Healthcare-seeking behavior (%) [30]
 Probability of no-healthcare-useUrban 9.7,Urban: Dirichlet with α1 = 107, α2 = 704, α3 = 269,
Rural: Dirichlet with α1 = 43, α2 = 394, α3 = 62
Rural 8.6
 Probability of self-treatment, seeking care in Community/Township Health Service CentersUrban 66.0,
Rural 79.0
 Probability of visiting doctors in county-level and above hospitalsUrban 24.3
Rural 12.4
Odds ratio of influenza-related hospitalization in high-risk groups compared to low-risk groups [29]3.39Lognormal with μ = 1.22, sd = 0.14
Odds ratio of influenza-related death in high-risk groups compared to low-risk groups [29]2.04Lognormal with μ = 0.71, sd = 0.08
Vaccine cost (US$ in 2013) [14]5.73 (95%UI 5.43–6.03)Bootstrap from data on influenza vaccine cost
Influenza outpatients visits and hospitalization costs (US$ in 2013) [32]Outpatients: 129 (95%UI 75–156)Bootstrap from data on national retrospective survey
Inpatients: 2735 (95%UI 1401–4482)
Duration of influenza episode for outpatients and inpatients (days) [37]Outpatients: 6.2 (SD 2.2)Bootstrap from data on national retrospective survey
Inpatients: 16.0 (SD 10.7)
Utility of influenza outpatients and inpatients [37]Outpatients: 0.5733 (95%UI 0.4650–0.6608)Bootstrap from data on national retrospective survey
Inpatients: 0.4128 (95%UI 0.1793–0.6380)
Background health utility [38]Urban
60–74 years: 0.8071 (SD 0.0039);
≥ 75 years: 0.7719 (SD 0.0093)
Rural
60–74 years: 0.7434 (SD 0.0031);
≥ 75 years: 0.6943 (SD 0.0078)
Normal distribution
Risk of infected from influenza in vaccinated group vs. unvaccinated group (odds ratio) [44]0.64 (0.52–0.78)Lognormal with μ = − 0.45, sd = 0.10
  1. *Used in one-way sensitivity analysis. 95%CI denotes 95% confidence interval; 95%UI denotes 95% uncertainty interval calculated by bootstrap methods