Browsing by Subject "Cost-effectiveness analysis"
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- ItemOpen AccessThe clinical and economic impact of point-of-care CD4 testing in Mozambique and other resource-limited settings: a cost-effectiveness analysis(Public Library of Science, 2014) Hyle, Emily P; Jani, Ilesh V; Lehe, Jonathan; Su, Amanda E; Wood, Robin; Quevedo, Jorge; Losina, Elena; Bassett, Ingrid V; Pei, Pamela P; Paltiel, A DavidEmily Hyle and colleagues conduct a cost-effectiveness analysis to estimate the clinical and economic impact of point-of-care CD4 testing compared to laboratory-based tests in Mozambique. Please see later in the article for the Editors' Summary
- ItemOpen AccessCost effectiveness of cryptococcal antigen screening as a strategy to prevent HIV-associated cryptococcal meningitis in South Africa(Public Library of Science, 2013) Jarvis, Joseph N; Harrison, Thomas S; Lawn, Stephen D; Meintjes, Graeme; Wood, Robin; Cleary, SusanObjectives Cryptococcal meningitis (CM)-related mortality may be prevented by screening patients for sub-clinical cryptococcal antigenaemia (CRAG) at antiretroviral-therapy (ART) initiation and pre-emptively treating those testing positive. Prior to programmatic implementation in South Africa we performed a cost-effectiveness analysis of alternative preventive strategies for CM. Design Cost-effectiveness analysis. METHODS: Using South African data we modelled the cost-effectiveness of four strategies for patients with CD4 cell-counts <100 cells/µl starting ART 1) no screening or prophylaxis (standard of care), 2) universal primary fluconazole prophylaxis, 3) CRAG screening with fluconazole treatment if antigen-positive, 4) CRAG screening with lumbar puncture if antigen-positive and either amphotericin-B for those with CNS disease or fluconazole for those without. Analysis was limited to the first year of ART. RESULTS: The least costly strategy was CRAG screening followed by high-dose fluconazole treatment of all CRAG-positive individuals. This strategy dominated the standard of care at CRAG prevalence ≥0.6%. Although CRAG screening followed by lumbar puncture in all antigen-positive individuals was the most effective strategy clinically, the incremental benefit of LPs and amphotericin therapy for those with CNS disease was small and additional costs were large (US$158 versus US$51per person year; incremental cost effectiveness ratio(ICER) US$889,267 per life year gained). Both CRAG screening strategies are less costly and more clinically effective than current practice. Primary prophylaxis is more effective than current practice, but relatively cost-ineffective (ICER US$20,495). CONCLUSIONS: CRAG screening would be a cost-effective strategy to prevent CM-related mortality among patients initiating ART in South Africa. These findings provide further justification for programmatic implementation of CRAG screening.
- ItemOpen AccessA Cost-Effectiveness Analysis of a Program to Control Rheumatic Fever and Rheumatic Heart Disease in Pinar del Rio, Cuba(Public Library of Science, 2015) Watkins, David A; Mvundura, Mercy; Nordet, Porfirio; Mayosi, Bongani MBACKGROUND: Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) persist in many low- and middle-income countries. To date, the cost-effectiveness of population-based, combined primary and secondary prevention strategies has not been assessed. In the Pinar del Rio province of Cuba, a comprehensive ARF/RHD control program was undertaken over 1986 - 1996. The present study analyzes the cost-effectiveness of this Cuban program. Methods and FINDINGS: We developed a decision tree model based on the natural history of ARF/RHD, comparing the costs and effectiveness of the 10-year Cuban program to a “do nothing” approach. Our population of interest was the cohort of children aged 5 - 24 years resident in Pinar del Rio in 1986. We assessed costs and health outcomes over a lifetime horizon, and we took the healthcare system perspective on costs but did not apply a discount rate. We used epidemiologic, clinical, and direct medical cost inputs that were previously collected for publications on the Cuban program. We estimated health gains as disability-adjusted life years (DALYs) averted using standard approaches developed for the Global Burden of Disease studies. Cost-effectiveness acceptability thresholds were defined by one and three times per capita gross domestic product per DALY averted. We also conducted an uncertainty analysis using Monte Carlo simulations and several scenario analyses exploring the impact of alternative assumptions about the program’s effects and costs. We found that, compared to doing nothing, the Cuban program averted 5051 DALYs (1844 per 100,000 school-aged children) and saved $7,848,590 (2010 USD) despite a total program cost of $202,890 over 10 years. In the scenario analyses, the program remained cost saving when a lower level of effectiveness and a reduction in averted years of life lost were assumed. In a worst-case scenario including 20-fold higher costs, the program still had a 100% of being cost-effective and an 85% chance of being cost saving. CONCLUSIONS: A 10-year program to control ARF/RHD in Pinar del Rio, Cuba dramatically reduced morbidity and premature mortality in children and young adults and was cost saving. The results of our analysis were robust to higher program costs and more conservative assumptions about the program’s effectiveness. It is possible that the program’s effectiveness resulted from synergies between primary and secondary prevention strategies. The findings of this study have implications for non-communicable disease policymaking in other resource-limited settings.
- ItemOpen AccessCost-effectiveness analysis of introducing HTLV-1 testing in South Africa(BioMed Central Ltd, 2015) Sykes, Wendy; Coleman, Charl; Beck, Genevieve; Mhlanga, Jabu; Hlela, Carol; Custer, Brian; Murphy, Edward; Vermeulen, MarionWe have previously reported a 2013 cross-sectional study of HTLV prevalence among 46,765 South African blood donors. Confirmed HTLV-1 prevalence was 0.16% in Black donors, 0.02% in both White and Coloured donors and 0% in south Asian donors, for an overall prevalence of 0.062% extrapolated to the current blood donor population. Using these data we estimated the cost effectiveness of potential HTLV screening strategies in preventing transfusion transmitted HTLV-1 infection (TTI). Five blood donor screening strategies were considered: no screening; HTLV testing of every donation; HTLV testing each donor one time only; HTLV testing of new donors only; and universal filter leukodepletion without HTLV testing.
- ItemOpen AccessCost-effectiveness of highly active antiretroviral therapy in South Africa(Public Library of Science, 2005) Badri, Motasim; Maartens, Gary; Mandalia, Sundhiya; Bekker, Linda-Gail; Penrod, John R; Platt, Robert W; Wood, Robin; Beck, Eduard JHealthcare costs for HIV-infected South African adults on HAART compared with costs for HIV-infected controls not on HAART. Authors conclude HAART is cost effective.
- ItemOpen AccessThe cost-effectiveness of monitoring strategies for antiretroviral therapy of HIV infected patients in resource-limited settings: software tool(Public Library of Science, 2015) Estill, Janne; Salazar-Vizcaya, Luisa; Blaser, Nello; Egger, Matthias; Keiser, OliviaBACKGROUND: The cost-effectiveness of routine viral load (VL) monitoring of HIV-infected patients on antiretroviral therapy (ART) depends on various factors that differ between settings and across time. Low-cost point-of-care (POC) tests for VL are in development and may make routine VL monitoring affordable in resource-limited settings. We developed a software tool to study the cost-effectiveness of switching to second-line ART with different monitoring strategies, and focused on POC-VL monitoring. METHODS: We used a mathematical model to simulate cohorts of patients from start of ART until death. We modeled 13 strategies (no 2 nd -line, clinical, CD4 (with or without targeted VL), POC-VL, and laboratory-based VL monitoring, with different frequencies). We included a scenario with identical failure rates across strategies, and one in which routine VL monitoring reduces the risk of failure. We compared lifetime costs and averted disability-adjusted life-years (DALYs). We calculated incremental cost-effectiveness ratios (ICER). We developed an Excel tool to update the results of the model for varying unit costs and cohort characteristics, and conducted several sensitivity analyses varying the input costs. RESULTS: Introducing 2 nd -line ART had an ICER of US$1651-1766/DALY averted. Compared with clinical monitoring, the ICER of CD4 monitoring was US$1896-US$5488/DALY averted and VL monitoring US$951-US$5813/DALY averted. We found no difference between POC- and laboratory-based VL monitoring, except for the highest measurement frequency (every 6 months), where laboratory-based testing was more effective. Targeted VL monitoring was on the cost-effectiveness frontier only if the difference between 1 st - and 2 nd -line costs remained large, and if we assumed that routine VL monitoring does not prevent failure. CONCLUSION: Compared with the less expensive strategies, the cost-effectiveness of routine VL monitoring essentially depends on the cost of 2 nd -line ART. Our Excel tool is useful for determining optimal monitoring strategies for specific settings, with specific sex-and age-distributions and unit costs.
- ItemOpen AccessA cost-effectiveness tool to guide the prioritization of interventions for rheumatic fever and rheumatic heart disease control in African nations(Public Library of Science, 2016) Watkins, David; Lubinga, Solomon J; Mayosi, Bongani; Babigumira, Joseph BAuthor Summary: Rheumatic heart disease is a major cause of cardiovascular morbidity and mortality in Africa. Although there are effective medications and surgical procedures for rheumatic heart disease, they are under-used. What is more, these interventions can be expensive--even if they are feasible and effective. Unfortunately, there are currently very few economic studies on rheumatic heart disease, leaving ministries of health with little guidance on how to choose among various interventions and allocate resources to control programs. Our study describes the methods and data we used to develop a cost-effectiveness analysis tool that was intended specifically for decision-making in African countries. In our study, we also illustrate, in a hypothetical low-income African country, how the tool could be used. In our illustrative example, a prevention-oriented approach would save money in the long term, although other interventions could be cost-effective and feasible if enough financial resources were present. These findings contrast with previous studies and make a strong case that rheumatic heart disease prevention could be a high-priority intervention in Africa. We are making our tool publicly available and anticipate that ministries of health will use it as they develop or expand their rheumatic heart disease control programs.
- ItemOpen AccessDesigning an optimal HIV programme for South Africa: Does the optimal package change when diminishing returns are considered?(2017) Chiu, Calvin; Johnson, Leigh F; Jamieson, Lise; Larson, Bruce A; Meyer-Rath, GesineAbstract Background South Africa has a large domestically funded HIV programme with highly saturated coverage levels for most prevention and treatment interventions. To further optimise its allocative efficiency, we designed a novel optimisation method and examined whether the optimal package of interventions changes when interaction and non-linear scale-up effects are incorporated into cost-effectiveness analysis. Methods The conventional league table method in cost-effectiveness analysis relies on the assumption of independence between interventions. We added methodology that allowed the simultaneous consideration of a large number of HIV interventions and their potentially diminishing marginal returns to scale. We analysed the incremental cost effectiveness ratio (ICER) of 16 HIV interventions based on a well-calibrated epidemiological model that accounted for interaction and non-linear scale-up effects, a custom cost model, and an optimisation routine that iteratively added the most cost-effective intervention onto a rolling baseline before evaluating all remaining options. We compared our results with those based on a league table. Results The rank order of interventions did not differ substantially between the two methods- in each, increasing condom availability and male medical circumcision were found to be most cost-effective, followed by anti-retroviral therapy at current guidelines. However, interventions were less cost-effective throughout when evaluated under the optimisation method, indicating substantial diminishing marginal returns, with ICERs being on average 437% higher under our optimisation routine. Conclusions Conventional league tables may exaggerate the cost-effectiveness of interventions when programmes are implemented at scale. Accounting for interaction and non-linear scale-up effects provides more realistic estimates in highly saturated real-world settings.
- ItemOpen AccessFinancing and cost-effectiveness analysis of public-private partnerships: provision of tuberculosis treatment in South Africa(BioMed Central Ltd, 2006) Sinanovic, Edina; Kumaranayake, LilaniBACKGROUND: Public-private partnerships (PPP) could be effective in scaling up services. We estimated cost and cost-effectiveness of different PPP arrangements in the provision of tuberculosis (TB) treatment, and the financing required for the different models from the perspective of the provincial TB programme, provider, and the patient. METHODS: Two different models of TB provider partnerships are evaluated, relative to sole public provision: public-private workplace (PWP) and public-private non-government (PNP). Cost and effectiveness data were collected at six sites providing directly observed treatment (DOT). Effectiveness for a 12-month cohort of new sputum positive patients was measured using cure and treatment success rates. Provider and patient costs were estimated, and analysed according to sources of financing. Cost-effectiveness is estimated from the perspective of the provider, patient and society in terms of the cost per TB case cured and cost per case successfully treated. RESULTS: Cost per case cured was significantly lower in PNP (US $354-446), and comparable between PWP (US $788-979) and public sites (US $700-1000). PPP models could significantly reduce costs to the patient by 64-100%. Relative to pure public sector provision and financing, expansion of PPPs could reduce government financing required per TB patient treated from $609-690 to $130-139 in PNP and $36-46 in PWP. CONCLUSION: There is a strong economic case for expanding PPP in TB treatment and potentially for other types of health services. Where PPPs are tailored to target groups and supported by the public sector, scaling up of effective services could occur at much lower cost than solely relying on public sector models.
- ItemOpen AccessImproving maternal care through a state-wide health insurance program: a cost and cost-effectiveness study in rural Nigeria(Public Library of Science, 2015) Gomez, Gabriela B; Foster, Nicola; Brals, Daniella; Nelissen, Heleen E; Bolarinwa, Oladimeji A; Hendriks, Marleen E; Boers, Alexander C; Eck, Diederik van; Rosendaal, Nicole; Adenusi, PejuBACKGROUND: While the Nigerian government has made progress towards the Millennium Development Goals, further investments are needed to achieve the targets of post-2015 Sustainable Development Goals, including Universal Health Coverage. Economic evaluations of innovative interventions can help inform investment decisions in resource-constrained settings. We aim to assess the cost and cost-effectiveness of maternal care provided within the new Kwara State Health Insurance program (KSHI) in rural Nigeria. Methods and FINDINGS: We used a decision analytic model to simulate a cohort of pregnant women. The primary outcome is the incremental cost effectiveness ratio (ICER) of the KSHI scenario compared to the current standard of care. Intervention cost from a healthcare provider perspective included service delivery costs and above-service level costs; these were evaluated in a participating hospital and using financial records from the managing organisations, respectively. Standard of care costs from a provider perspective were derived from the literature using an ingredient approach. We generated 95% credibility intervals around the primary outcome through probabilistic sensitivity analysis (PSA) based on a Monte Carlo simulation. We conducted one-way sensitivity analyses across key model parameters and assessed the sensitivity of our results to the performance of the base case separately through a scenario analysis. Finally, we assessed the sustainability and feasibility of this program’s scale up within the State’s healthcare financing structure through a budget impact analysis. The KSHI scenario results in a health benefit to patients at a higher cost compared to the base case. The mean ICER (US$46.4/disability-adjusted life year averted) is considered very cost-effective compared to a willingness-to-pay threshold of one gross domestic product per capita (Nigeria, US$ 2012, 2,730). Our conclusion was robust to uncertainty in parameters estimates (PSA: median US$49.1, 95% credible interval 21.9-152.3), during one-way sensitivity analyses, and when cost, quality, cost and utilization parameters of the base case scenario were changed. The sustainability of this program’s scale up by the State is dependent on further investments in healthcare. CONCLUSIONS: This study provides evidence that the investment made by the KSHI program in rural Nigeria is likely to have been cost-effective; however, further healthcare investments are needed for this program to be successfully expanded within Kwara State. Policy makers should consider supporting financial initiatives to reduce maternal mortality tackling both supply and demand issues in the access to care.
- ItemOpen AccessMobile HIV screening in Cape Town, South Africa: clinical impact, cost and cost-effectiveness(Public Library of Science, 2014) Bassett, Ingrid V; Govindasamy, Darshini; Erlwanger, Alison S; Hyle, Emily P; Kranzer, Katharina; van Schaik, Nienke; Noubary, Farzad; Paltiel, A David; Wood, Robin; Walensky, Rochelle PBACKGROUND: Mobile HIV screening may facilitate early HIV diagnosis. Our objective was to examine the cost-effectiveness of adding a mobile screening unit to current medical facility-based HIV testing in Cape Town, South Africa. Methods and FINDINGS: We used the Cost Effectiveness of Preventing AIDS Complications International (CEPAC-I) computer simulation model to evaluate two HIV screening strategies in Cape Town: 1) medical facility-based testing (the current standard of care) and 2) addition of a mobile HIV-testing unit intervention in the same community. Baseline input parameters were derived from a Cape Town-based mobile unit that tested 18,870 individuals over 2 years: prevalence of previously undiagnosed HIV (6.6%), mean CD4 count at diagnosis (males 423/µL, females 516/µL), CD4 count-dependent linkage to care rates (males 31%-58%, females 49%-58%), mobile unit intervention cost (includes acquisition, operation and HIV test costs, $29.30 per negative result and $31.30 per positive result). We conducted extensive sensitivity analyses to evaluate input uncertainty. Model outcomes included site of HIV diagnosis, life expectancy, medical costs, and the incremental cost-effectiveness ratio (ICER) of the intervention compared to medical facility-based testing. We considered the intervention to be "very cost-effective" when the ICER was less than South Africa's annual per capita Gross Domestic Product (GDP) ($8,200 in 2012). We projected that, with medical facility-based testing, the discounted (undiscounted) HIV-infected population life expectancy was 132.2 (197.7) months; this increased to 140.7 (211.7) months with the addition of the mobile unit. The ICER for the mobile unit was $2,400/year of life saved (YLS). Results were most sensitive to the previously undiagnosed HIV prevalence, linkage to care rates, and frequency of HIV testing at medical facilities. CONCLUSION: The addition of mobile HIV screening to current testing programs can improve survival and be very cost-effective in South Africa and other resource-limited settings, and should be a priority.
- ItemOpen AccessModelling the cost-effectiveness of a new infant vaccine to prevent tuberculosis disease in children in South Africa(2014-09-16) Channing, Liezl; Sinanovic, EdinaAbstract Background Tuberculosis remains the leading cause of death in South Africa. A number of potential new TB vaccine candidates have been identified and are currently in clinical trials. One such candidate is MVA85A. This study aimed to estimate the cost-effectiveness of adding the MVA85A vaccine as a booster to the BCG vaccine in children from the perspective of the South African government. Methods The cost-effectiveness was assessed by employing Decision Analytic Modelling, through the use of a Markov model. The model compared the existing strategy of BCG vaccination to a new strategy in which infants receive BCG and a booster vaccine, MVA85A, at 4 months of age. The costs and outcomes of the two strategies are estimated through modelling the vaccination of a hypothetical cohort of newborns and following them from birth through to 10 years of age, employing 6-monthly cycles. Results The results of the cost-effectiveness analysis indicate that the MVA85A strategy is both more costly and more effective – there are fewer TB cases and deaths from TB than BCG alone. The South African government would need to spend an additional USD 1,105 for every additional TB case averted and USD 284,017 for every additional TB death averted. The threshold analysis shows that, if the efficacy of the MVA85A vaccine was 41.3% (instead of the current efficacy of 17.3%), the two strategies would have the same cost but more cases of TB and more deaths from TB would be prevented by adding the MVA85A vaccine to the BCG vaccine. In this case, the government chould consider the MVA85A strategy. Conclusions At the current level of efficacy, the MVA85A vaccine is neither effective nor cost-effective and, therefore, not a good use of limited resources. Nevertheless, this study contributes to developing a standardized Markov model, which could be used, in the future, to estimate the potential cost-effectiveness of new TB vaccines compared to the BCG vaccine, in children between the ages of 0–10 years. It also provides an indicative threshold of vaccine efficacy, which could guide future development.
- ItemOpen AccessA multifaceted intervention to improve the quality of care of children in district hospitals in Kenya: a cost-effectiveness analysis(Public Library of Science, 2012) Barasa, Edwine W; Ayieko, Philip; Cleary, Susan; English, MikeA cost-effective analysis conducted by Edwine Barasa and colleagues estimates that a complex intervention aimed at improving quality of pediatric care would be affordable and cost-effective in Kenya.
- ItemOpen AccessRapid diagnosis of tuberculosis with the Xpert MTB/RIF assay in high burden countries: a cost-effectiveness analysis(Public Library of Science, 2011) Vassall, Anna; van Kampen, Sanne; Sohn, Hojoon; Michael, Joy S; John, K R; den Boon, Saskia; Davis, J Lucian; Whitelaw, Andrew; Nicol, Mark P; Gler, Maria Tarcela; Khaliqov, Anar; Zamudio, Carlos; Perkins, Mark D; Boehme, Catharina C; Cobelens, FrankBackground: Xpert MTB/RIF (Xpert) is a promising new rapid diagnostic technology for tuberculosis (TB) that has characteristics that suggest large-scale roll-out. However, because the test is expensive, there are concerns among TB program managers and policy makers regarding its affordability for low- and middle-income settings. Methods and Findings: We estimate the impact of the introduction of Xpert on the costs and cost-effectiveness of TB care using decision analytic modelling, comparing the introduction of Xpert to a base case of smear microscopy and clinical diagnosis in India, South Africa, and Uganda. The introduction of Xpert increases TB case finding in all three settings; from 72%–85% to 95%–99% of the cohort of individuals with suspected TB, compared to the base case. Diagnostic costs (including the costs of testing all individuals with suspected TB) also increase: from US$28–US$49 to US$133–US$146 and US$137–US$151 per TB case detected when Xpert is used "in addition to" and "as a replacement of" smear microscopy, respectively. The incremental cost effectiveness ratios (ICERs) for using Xpert "in addition to" smear microscopy, compared to the base case, range from US$41–$110 per disability adjusted life year (DALY) averted. Likewise the ICERS for using Xpert "as a replacement of" smear microscopy range from US$52–$138 per DALY averted. These ICERs are below the World Health Organization (WHO) willingness to pay threshold. Conclusions: Our results suggest that Xpert is a cost-effective method of TB diagnosis, compared to a base case of smear microscopy and clinical diagnosis of smear-negative TB in low- and middle-income settings where, with its ability to substantially increase case finding, it has important potential for improving TB diagnosis and control. The extent of cost-effectiveness gain to TB programmes from deploying Xpert is primarily dependent on current TB diagnostic practices. Further work is required during scale-up to validate these findings.
- ItemOpen AccessScaling up the 2010 World Health Organization HIV Treatment Guidelines in resource-limited settings: a model-based analysis(Public Library of Science, 2010) Walensky, Rochelle P; Wood, Robin; Ciaranello, Andrea L; Paltiel, A David; Lorenzana, Sarah B; Anglaret, Xavier; Stoler, Adam W; Freedberg, Kenneth A; Investigators, for the CEPAC-InternationalRochelle Walensky and colleagues use a model-based analysis to examine which of the 2010 WHO antiretroviral therapy guidelines should be implemented first in resource-limited settings by ranking them according to survival, cost-effectiveness, and equity.
- ItemOpen AccessSystematic review of TST responses in people living with HIV in under-resourced settings: implications for isoniazid preventive therapy(Public Library of Science, 2012) Kerkhoff, Andrew D; Kranzer, Katharina; Samandari, Taraz; Nakiyingi-Miiro, Jessica; Whalen, Christopher C; Harries, Anthony D; Lawn, Stephen DBACKGROUND: People living with HIV (PLWH) who have positive tuberculin skin tests (TST) benefit from isoniazid preventive therapy (IPT) whereas those testing TST-negative do not. Revised World Health Organization guidelines explicitly state that assessment of TST is not a requirement for initiation of IPT. However, it is not known what proportions of patients will benefit from IPT if implemented without targeting according to TST status. We therefore determined the proportions of PLWH who test TST-positive. METHODOLOGY/PRINCIPAL FINDINGS: We systematically reviewed the literature published between January 1990 and February 2012 to determine the proportions of patients without active tuberculosis attending HIV care services in low and middle-income countries who tested TST-positive (≥5 mm induration). Proportions were also determined for different CD4 count strata. Data from 19 studies with 9,478 PLWH from sub-Saharan Africa, Asia and Central and South America were summarized. The vast majority were not receiving antiretroviral therapy (ART). A sub-analysis was conducted of 5 studies (5,567 subjects) from high TB prevalence countries of PLWH with negative TB screens attending HIV care and treatment settings for whom CD4 stratified data were available. The median proportion of PLWH testing TST-positive overall was 22.8% (range, 19.5-32.6%). The median (range) proportions with CD4 cell counts of <200, 200-499 or ≥500 cells/µL who tested positive were 12.4% (8.2-15.3%), 28.4% (20.1-36.9%) and 37.4% (31.3-56.3%), respectively. Heterogeneity in the data precluded calculation of pooled summary estimates. Conclusions/Significance In most settings, if IPT is administered to PLWH pre-ART without assessment of TST status, only a minority of those treated are likely to benefit, especially among those with the lowest CD4 cell counts. This may be inefficient use of resources and cost-effectiveness analyses should take this into account. Local knowledge of TST response rates may help inform policies. New simple means of identifying those who will benefit from IPT are needed to permit appropriate targeting of this intervention.