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Table 1 Model parameters

From: Public health impact and cost effectiveness of routine childhood vaccination for hepatitis a in Jordan: a dynamic model approach

Parameter Base Case Range Distribution Reference
Demography
 Population 2014 8,117,564 Fixed   [10]
 Age Specific All-cause Mortality Varies Fixed   [8]
Infection
Force of Infection   Fixed   [20, 44]
 Scale parameter 0.854327 Fixed   
  Shape parameter 0.00159689 Fixed   
  Shape parameter 11.5766 Fixed   
Duration of Maternal Immunity (mo) 6.5 Fixed   [45]
Latency period (d) 14 Fixed   [46, 47]
Age-specific mean duration of infectiousness (wk)   Fixed   [48, 49]
 0–4 y 3.5    
 5–9 y 3.0    
 10+ y 2.5    
Vaccine
Vaccine efficacy, one does only (%) 100 87.3–100 Derived Distribution [22]
Vaccine efficacy, two doses (%) 100 87.3–100 Derived Distribution Assumed
Median duration of vaccine-derived immunity, one dose only (y) 21 20.3–21.9 Gamma (2647.1, 0.0079) Assumed
Median duration of vaccine-derived immunity, two doses (y) 32 30.9–33.4 Gamma (2517.63,0.127) [23]
Vaccination Strategy
Vaccine uptake, universal strategy, first dose (%) 95% 80–97 Beta (34.37426,1.0007488) Assumed
Vaccine adherence, probability of second dose given first dose (%) 95% 70–95 Beta (27.15759,2.49654) Assumed
Clinical Outcomes
 Under reporting factor 11.76 Fixed   Estimated
 Probability an infection is icteric Varies Fixed   [20]
Proportion of icteric infections hospitalized (%)     [21]
  ≤ 4 y 0.395   Dirichlet(D1)a  
 5–14 y 1.45   Dirichlet(D2)  
 15–39 y 1.91   Dirichlet(D3)  
 40–59 y 1.57   Dirichlet(D4)  
 60+ y 1.7   Dirichlet(D5)  
Probability of fulminant hepatitis A from an icteric infection (%)     [21]
  ≤ 4 y 0.0323   Dirichlet(D1)  
 5–14 y 0.00425   Dirichlet(D2)  
 15–39 y 0.0578   Dirichlet(D3)  
 40–59 y 0.468   Dirichlet(D4)  
 60+ y 0.68   Dirichlet(D5)  
Probability of liver transplant from an icteric infection (%)     [21]
  ≤ 4 y 0.00606   Dirichlet(D1)  
 5–14 y 0.000797   Dirichlet(D2)  
 15–39 y 0.0108   Dirichlet(D3)  
 40–59 y 0.0877   Dirichlet(D4)  
 60+ y 0.017   Dirichlet(D5)  
Probability of death from an icteric infection (%)     [21]
  ≤ 4 y 0.00468   Dirichlet(D1)  
 5–14 y 0.000616   Dirichlet(D2)  
 15–39 y 0.00838   Dirichlet(D3)  
 40–59 y 0.0678   Dirichlet(D4)  
 60+ y 0.456   Dirichlet(D5)  
Probability of death during first year of liver transplant (%) 11.6 6.0–42.0 Beta (1.14982, 8.76245) [50]
Probability of death from year 2 and beyond after liver transplant (%) 4.4 2.4–11.0 Beta (3.80137, 82.5935) [50]
Duration of outpatient icteric infection (d) 34.4 17–40 Gamma (34.37,1.00) [51]
Duration of inpatient icteric infection (d) 67.8 27–78 Gamma (27.16,2.50) [51]
Economic Parameters
Cost of one-dose vaccine (2015 $) 10.00 8.00–14.00 Gamma (42.6844, 0.234277,1.1,3) Estimated
Test Costs 22.55 Fixed   [26]
Cost of one-dose administration 1.91 Fixed   Estimated
outpatient cost $15.06 10–25 Gamma (8.71228, 7.77408) [27]
outpatient visits 3 1–4 Estimated
hospitalization cost $ 111.5 80–150 Gamma (6.43896, 81.4262) [26]
hospitalization duration 4.5 3–7 Estimated
fulminant cost $35,715 32,143–39,278 Gamma (385.022, 92.7609) [26]
annual cost of patients with liver transplant (1st year) $70,000 50,000–90,000 Gamma (47.0596, 1487.48) [26]
annual cost of patients with liver transplant (subsequent years) 43,203 34,563–51,843 Gamma(96.0533, 449.781) Estimated
Public health cost of a reported infection (2013 $) 0 0–15 Gamma(1.092722,3.660584) Estimated
work loss, outpatient (d) 15.5 7–18 Gamma(30.51056,0.508021) [51]
work loss, inpatient (d) 33.2 10–25 Gamma(75.2776,0.4410342) [51]
work loss, fulminant (d) 33.2 10–25 Gamma(75.2776,0.4410342) [51]
work loss, year of transplant (d)     [25]
 0–17 y 153.2 145–160 Gamma(1602.9, 0.0955766)  
 18–40 y 245 238–253 Gamma (4099.41, 0.0597646)  
 41–55 y 271 268–274 Gamma (31,347.9, 0.00864492)  
 56–62 y 288 284–291 Gamma (26,011.2, 0.0110721)  
 63+ 314 306–321 Gamma (6733.62, 0.0466316)  
Labor force participation (%)     [52]
 16–19 y 3.15 1–28 Beta[1.4452,44.4342]  
 20–24 y 33.8 31–72 Beta[6.57547,12.8786]  
 25–34 y 64.0 57–70 Beta[133.435,75.0572]  
 35–44 y 59.6 51 – 71 Beta[54.5338,36.9658]  
 45–54 y 47.1 35–59 Beta[30.8364,34.6337]  
 55–64 y 30.7 0–62 Beta[2.30395,5.20078]  
 65+ 10.0 0–23 Beta[2.51432,22.6289]  
Median Monthly earnings (2014 $)     [53]
  < 25 y 292 137–350 Gamma(13.6337, 21.4175)  
 25+ 365 250–650 Gamma(28.8788, 10.1112)  
 Discount rate per year, % 3 0–5   Assumed
Utilities
Average population norms     [31]
 20–29 y .920 0.913–0.927 Beta(5307.7008, 461.5392)  
 30–39 y .905 0.898–0.912 Beta(6099.1932,640.2468)  
 40–49 y .874 0.867–0.882 Beta(6572.4195,947.5113)  
 50–59 y .848 0.840–0.857 Beta(5810.9376,1041.5832)  
 60–69 y .824 0.812–0.836 Beta(3187.1645,680.7536)  
 70–79 y .785 0.771–0.798 Beta(2791.9027,764.6613)  
 80+ y .744 0.720–0.768 Beta(944.3511,324.9380)  
Persons with anicteric hepatitis A .830 0.789–0.867 Beta(291.9525,59.7975) [21]
Persons with icteric hepatitis A .642 0.607–0.682 Beta(410.1317,228.3050) [29]
Persons with liver transplant .730 0.630–0.840 Beta(49.4052,18.2732) [30]
  1. Base-case model parameters, estimates, corresponding distributions and ranges for deterministic and probabilistic sensitivity analysis, and data source references
  2. aParameters for the Dirichlet distributions are as follows: D1 = (97.0207,0.385265,0.00456518,0.031484,0.00590325), D2 = (349.97,5.13289,0.00218903,0.0150967,0.00283064), D3 = (458.787,8.95484,0.0392421,0.270635,0.0507441), D4 = (377.566,6.07215,0.261759,1.80523,0.338481), D5 = (161.413,2.82536,0.757196,1.13014,0.0282536)