Additional file 1 of Costs of syringe vending machines in Tbilisi, Georgia

Additional file 1. Cost data and analysis spreadsheet

Forest plot of treatment attrition among HIV-infected FSWs, including (A) treatment discontinuation (B) loss to follow-up on ART (C) death on ART and (D) ART-experienced but no longer on ART.

<p>Study estimates are grouped by country income and ordered by time on ART. The star symbol (*) highlights the study estimates (one per study population) included in the pooled overall or subgroup estimates. For studies providing estimates over multiple time-periods, only one estimate was used for pooling (the most recent estimate from that study). I² and p-values are the measures of heterogeneity used. ART  =  antiretroviral therapy, FSW  =  female sex workers, CI  =  confidence interval, NR  =  not reported, n =  number of FSWs with each outcome, N =  sample size of FSWs available for each outcome, N_p =  number of independent study populations, m =  median, LFU  =  lost to follow-up.</p

Fig 2 -

(A) Estimated cumulative direct costs and indirect costs of EL versus SQ. (B) Net economic benefit of EL versus SQ including direct and indirect costs. For the net economic benefit of EL, 3 economic perspectives were used: Perspective A–Direct costs only with no integration of testing. Perspective B–Direct costs (no integration of testing) and productivity gains. Perspective C–Partially integrated direct costs and productivity gains. All costs are in 2018 US$ and discounted at 3.5% per annum; healthcare costs were applied to all liver disease states pre- and post-cure; staffing costs were applied to all testing and treatment interactions; one-third of initial screening was assumed to not incur staffing costs and had reduced HCV RNA testing kit cost in the EL scenario with economic perspective C. The solid line and shading indicate the median and 95% UIs across 1,151 model fits. EL, elimination; HCV, hepatitis C virus; SQ, status quo; UI, uncertainty interval.</p

Forest plot of (A) median CD4 count and (B) median gains in CD4 count among HIV-infected FSWs on ART and starting ART.

<p>Study estimates are grouped by country income and ordered by time on ART. ^a N refers to a subset of FSWs who were eligible for ART upon HIV diagnosis and enrolled in HIV care following HIV diagnosis. ART  =  antiretroviral, FSW  =  female sex workers, CI  =  confidence interval, NR  =  not reported, N =  sample size of FSWs available for each outcome, N_p =  number of independent study populations, m =  median, IQR  =  interquartile range.</p

Model projections of the HCV-related morbidity and mortality due to the SQ and EL scenarios over 2018 to 2030.

DALYs are discounted at a rate of 3.5% per annum. The values represent the median and 95% UIs across 1,151 model fits.</p

Univariate sensitivity analyses on the year that the HCV EL scenario becomes cost-saving.

For each sensitivity analysis scenario, the estimated year that HCV elimination becomes cost-saving or, equivalently, the year when overall net economic benefit becomes positive, is taken from economic perspective C, compared to SQ. The bars show the median across 1,151 model runs for the various sensitivity analyses. DAA, direct-acting antiviral; DC, decompensated cirrhosis; EL, elimination; ESLD, end-stage liver disease; HCC, hepatocellular carcinoma; HCV, hepatitis C virus; PWID, people who inject drugs; SQ, status quo; SVR, sustained virological response.</p

Productivity parameters and disability weights used in the model.

Productivity parameters and disability weights used in the model.</p

Fig 1 -

Estimated health impact of the SQ and EL scenarios on (A) the projected number of people living with hepatitis C and (B) the number of annual hepatitis C–related deaths. The solid line and shading indicate the median and 95% UIs across 1,151 model fits. EL, elimination; HCV, hepatitis C virus; SQ, status quo; UI, uncertainty interval.</p

Supporting information.

Additional details of the model and methods; input parameters and calibration data; additional results tables and figures; CHEERS checklist; and references. Methods A. Productivity gains from people cured of HCV. Methods B. Productivity gains from averted deaths. Fig A. Simplified HCV screening and treatment model schematic. The full HCV transmission model schematic including demographic and behavioural compartments, disease progression stages, HCV infection and transmission dynamics, and complete screening and treatment cascade has been shown previously. Fig B. Schematic of productivity model. Parameters used in the productivity model are in Table 2, with specific reference to † and ‡. §Treatment rates may be different among PWID and cirrhotic patients, hence we allow and . Fig C. Estimated direct annual costs of testing, treatment, and healthcare management for the SQ and EL scenarios. Model projections showing the estimated direct annual costs of testing, treatment, and healthcare management for the SQ and EL scenarios. The direct annual cost of elimination differs depending on whether testing is integrated or not. All costs are in 2018 US$and discounted at 3.5$. The solid line and shading indicate the median and 95% UIs across 1,151 model fits. Fig E. Univariate sensitivity analyses on overall net economic benefit by 2030 for the EL scenario. For each sensitivity analysis scenario, the overall net economic benefit by 2030 for HCV elimination is taken from economic perspective C, compared to SQ. The dashed vertical line indicates the threshold where HCV elimination becomes cost-saving, i.e., there is a positive net economic benefit by 2030. The bars show the median across 1,151 model runs for the various sensitivity analyses. Fig F. Heat map showing correlation coefficients between parameters across final baseline model fits. Refer to S1 Table for the symbols corresponding to each of the model parameters. Note that baseline model parameters that are point estimates are not shown. These include the ageing parameters (η1, η2), the age-specific death rates for the young and young adult categories (μ1,g, μ2,g), and the relative risk of progression from DC to HCC if SVR (ϵDH), which is assumed to be unity (S1 Table). In the heat map shown, between any pair of parameters, a correlation coefficient of “0” implies that no correlation is present, while a “1” or “-1” suggests a perfect positive or negative linear correlation, respectively. The age-specific death rate parameter μ3,g was derived by fitting to population growth trends, so would be expected to be correlated to population growth rate as shown. All other parameter sets for the baseline model (n = 1,151 final model fits) do not appear to be strongly correlated to each other. Table A. Baseline HCV transmission model parameters with associated uncertainty ranges. Rates are per year. Table B. Screening and treatment model parameters with associated uncertainty ranges. Rates are per year. EL, elimination scenario; SQ, status quo. Table C. Demographic and epidemiological data used to calibrate and fit the model. Table D. Annual pre-intervention treatment numbers by province and in total. Table E. Model projections of the HCV-related morbidity and mortality for the SQ and EL scenarios over 2018–2030 or over 2018–2050. DALYs are discounted at a rate of 3.5% per annum. The values represent the median and 95% UIs across 1,151 model fits. Table F. Breakdown of absolute cost estimates for the economic components of the SQ and EL scenarios taking 3 different economic perspectives (A, B, and C). Total costs, combined and split by direct and indirect costs, are determined over 2018–2030 and over 2018–2050. Costs are discounted at a rate of 3.5% per annum and are presented in 2018 US$. The values represent the median and 95$. The values represent the median and 95% UIs across 1,151 model fits. Table H. ICERs for the modelled EL scenarios over 2018–2050 for 3 economic perspectives. Costs and DALYs are discounted at 3.5% per annum, with costs presented in 2018 US$. Perspective A includes direct costs only (costs for testing, treatment, and healthcare management). Perspective B includes direct costs (perspective A) plus productivity costs. Perspective C includes partially integrated direct costs and productivity costs. The values represent the median and 95$. The values represent the median and 95% UIs across 1,151 model fits. Checklist A. Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. DALY, disability-adjusted life year; DC, decompensated cirrhosis; EL, elimination; HCC, hepatocellular carcinoma; HCV, hepatitis C virus; ICER, incremental cost-effectiveness ratio; PWID, people who inject drugs; SQ, status quo; SVR, sustained virological response; UI, uncertainty interval. (PDF)</p

Direct testing, treatment, and healthcare management costs used in the modelling analyses.

This includes the unit costs of HCV screening and treatment and estimated annual costs of managing chronic HCV infection by disease progression stage. These cost estimates are used in both intervention scenarios (status quo and elimination) and for each of the economic perspectives (A, B, and C). All costs are in 2018 US dollars (US$).</p