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Table 2 Parameters including base values, range, distributions, and sources. All costs are in 2015 United States Dollars

From: Tenofovir disoproxil fumarate in pregnancy for prevention of mother to child transmission of hepatitis B in a rural setting on the Thailand-Myanmar border: a cost-effectiveness analysis

Parameter Base value Range Source
Prevalence of HBsAg 0.062 0.057–0.067 [21] with 95% CI
Prevalence of HBeAg carrier if HBsAg+ 0.307 0.273–0.341 30.7% of the HBsAg positive women [21]
Prevalence of HBV DNA > 200,000 IU per mL if HBsAg+ 0.252 0.203–0.301 82% of the HBeAg positive women [22]
Probability of attending ANC at least 7 days before delivery can receive additional testing 0.946 0.944–0.998 SMRU data with 95% CI
Probability of attending ANC at least 3 m before delivery so can receive TDF 0.663 0.660–0.666 SMRU data with 95% CI
Proportion of women receiving TDF that would receive 5 m of treatment 0.720 0.716–0.724 SMRU data with 95% CI
Probability of clinic delivery after attending ANC 0.888 0.850–0.910 [21] SMRU data with 95% CI
Probability that infants birthed at home after attending ANC will receive HBV birth dose vaccine at the clinic (present within 12 h) 0.272 0.264–0.280 SMRU data with 95% CI
Probability of HBV perinatal infection for HBsAg+, HBeAg- mothers without vaccinations 0.110 0.070–0.150 [23,24,25,26] with low from [24] and high from [23]
Probability of HBV perinatal infection for HBeAg+ mothers without vaccinations 0.840 0.790–0.900 [23,24,25, 27] with low from [25] and high from [26]
Probability of HBV perinatal infection for HBsAg+, HBeAg- mothers with vaccinations 0.038 0.031–0.045 [28]
Probability of HBV perinatal infection for HBeAg+ mothers with vaccinations 0.210 0.143–0.278 [28,29,30]
Probability of HBV perinatal infection for HBsAg+, HBsAg- mothers with vaccinations and HBIG 0.010 0.001–0.030 [28]
Probability of HBV perinatal infection for HBeAg+ mothers with vaccinations and HBIG 0.180 0.100–0.260 [4]
Probability of HBV perinatal infection for HBsAg+, HBsAg- mothers with TDF, no HBIG 0.0025 0.0005–0.0055 Assumed based on midpoints of HBIG transmissions
Probability of HBV perinatal infection for HBeAg+ mothers with less than five months of TDF 0.0500 0.0070–0.0930 Assumed based on midpoints of HBIG transmissions
Probability of HBV perinatal infection for HBeAg+ mothers with five months of TDF 0.025 0.0001–0.050 Assumed based on lower points of HBIG transmissions
Probability of HBV perinatal infection for HBsAg+, HBeAg- mothers with TDF and vaccinations 0.0013 0.0003–0.0028 Assumed based on midpoints of TDF
Probability of HBV perinatal infection for HBeAg+ mothers with TDF and vaccinations 0.0128 0.0025–0.0280 Assumed based on midpoints of TDF
Probability of HBV perinatal infection for HBsAg+, HBeAg- mothers with TDF, vaccinations and HBIG 0.0003 0.00003–0.0006 Assumed based on midpoints of TDF and vaccinations
Probability of HBV perinatal infection for HBeAg+ mothers with TDF, vaccinations and HBIG 0.0005 0.0003–0.0013 Assumed based on midpoints of TDF and vaccinations
Probability of having a hepatic flare after stopping TDF 0.500 0.352–0.648 [31]
Probability that the hepatic flare requires treatment 0.308 0.163–0.453 [31]
Sensitivity of the RDT for HBsAg 0.980 0.631–1.000 Assumed based on [21]
Specificity of the RDT for HBsAg 0.989 0.969–1.000 Assumed based on [21]
Sensitivity of the confirmatory test for HBeAg 1.000 0.900–1.000 [32] with assumed range
Specificity of the confirmatory test for HBeAg 1.000 0.900–1.000 [32] with assumed range
Sensitivity of HBV DNA PCR 0.953 0.700–1.000 [33] with assumed range
Specificity of HBV DNA PCR 0.997 0.700–1.000 [33] with assumed range
Cost of HBV vaccinations 6.65 3.33–9.98 SMRU records + 50%. Cost of single vaccination at birth plus three doses of HBV diphtheria tetanus and pertussis combined vaccine given at 2, 4 and 6 months
Cost of RDT for HBsAg 1.3 0.65–1.96 SMRU records + 50%
Cost of confirmatory test 21.19 10.60–31.79 SMRU records + 50%
Cost of a PCR test 32.60 16.30 SMRU records + 50%
Cost per dose of HBIG 88.02 44.01–132.03 SMRU records + 50%
Cost per month of TDF 11.74 5.87–17.60 TDF Thailand bought
Cost for hepatic flare monitoring 6.85 3.42–10.27 ALT, Creatine and phosphate tests, twice each.
Cost of a hepatic flare 44.99 22.49–67.48 TDF for three additional months, five ALT tests
  1. ALT Alanine aminotransferase, ANC antenatal care, CI Confidence interval, DNA Deoxyribonucleic acid, EGA estimated gestational age, HBV hepatitis B Virus, HBIG hepatitis B immunoglobulin, HBeAg hepatitis B envelope antigen, HBsAg hepatitis B surface antigen, TDF Tenofovir Disoproxil Fumarate, PCR Polymerase Chain Reaction, SMRU Shoklo Malaria Research Unit. Vaccinations, Birth dose and 3 follow up vaccinations