Comparative effectiveness research
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Background: Although the number of infected people receiving highly active anti-retroviral therapy (HAART) in low- and middle- income countries increased dramatically, optimal disease management is not well defined.

Methods: We developed a model to compare the costs and benefits of three types of Human Immunodeficiency Virus monitoring strategies: symptom-based strategies, CD4-based strategies, and CD4 plus viral load strategies for starting, switching, and stopping HAART. We used clinical and cost data from southern Africa and performed a cost-effectiveness analysis. All assumptions were tested in sensitivity analyses.

Results: Compared to the symptom-based approaches, monitoring CD4 every 6 months and starting treatment at a threshold of 200 cells/μl was associated with a life expectancy gain of 6.5 months (61.9 vs. 68.4) and a discounted lifetime cost savings of $464 per person (4,069 vs. 3,605 discounted 2007 USD). CD4-based strategies where treatment was started at the higher threshold of 350 cells/μl provided an additional life expectancy gain of 5.3 months at a cost effectiveness of $107 per life-year gained compared to a threshold of 200 cells/μl. Monitoring viral load with CD4 was more expensive than monitoring CD4 alone, added 2.0 months of life, and had an incremental cost-effectiveness ratio of $5,414/life-year gained relative to monitoring CD4 counts. In sensitivity analyses, the cost-savings from CD4 monitoring compared to symptom-based approaches was sensitive to cost of inpatient care, and the cost-effectiveness of viral load monitoring was influenced by the per-test costs and rates of virologic failure.

Conclusions: Use of CD4 monitoring and early HAART initiation in southern Africa provides large health benefits relative to symptom-based approaches for HAART management. In southern African countries with relatively high costs of hospitalization, CD4 monitoring would likely reduce total health care expenditures. The cost-effectiveness of viral load monitoring depends on test prices and rates of virologic failure.

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Journal Articles
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Journal Publisher
Archives of Internal Medicine
Authors
Eran Bendavid
Eran Bendavid
Sean Young
David Katzenstein
Ahmed Bayoumi
Gillian D. Sanders
Douglas K. Owens
Douglas K. Owens
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BACKGROUND: Although evidence suggests that a higher hemodialysis dose and/or frequency may be associated with improved outcomes, the cost-effectiveness of a daily hemodialysis strategy for critically ill patients with acute kidney injury (AKI) is unknown. METHODS: We developed a Markov model of the cost, quality of life, survival, and incremental cost-effectiveness of daily hemodialysis, compared with alternate-day hemodialysis, for patients with AKI in the intensive care unit (ICU). We employed a societal perspective with a lifetime analytic time horizon. We modeled the efficacy of daily hemodialysis as a reduction in the relative risk of death on the basis of data reported in the 2004 clinical trial published by Schiffl et al. We performed 1- and 2-way sensitivity analyses across cost, efficacy, and utility input variables. The main outcome measure was cost per quality-adjusted life-year (QALY). RESULTS: In the base case for a 60-year-old man, daily hemodialysis was projected to add 2.14 QALYs and $10,924 in cost. We found that the cost-effectiveness of daily hemodialysis compared with alternate-day hemodialysis was $5084 per QALY gained. The incremental cost-effectiveness ratio became less favorable (>$50,000 per QALY gained) when the maintenance hemodialysis rate of the daily hemodialysis group was varied to more than 27% and when the difference in 14-day postdischarge mortality between the alternatives was varied to less than 0.5%. CONCLUSION: Daily hemodialysis is a cost-effective strategy compared with alternate-day hemodialysis for patients with severe AKI in the ICU.

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Publication Type
Journal Articles
Publication Date
Journal Publisher
Archives of Internal Medicine
Authors
Amar Desai
Baras J
Berk B
Nakajima A
Alan M. Garber
Douglas K. Owens
Douglas K. Owens
Glenn Chertow
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Objective
Inadequate adherence to highly active antiretroviral therapy (HAART) may lead to poor health outcomes and the development of HIV strains that are resistant to HAART. The authors developed a model to evaluate the cost-effectiveness of counseling interventions to improve adherence to HAART among men who have sex with men (MSM).

Methods
The authors developed a dynamic compartmental model that incorporates HIV treatment, adherence to treatment, and infection transmission and progression. All data estimates were obtained from secondary sources. The authors evaluated a counseling intervention given prior to initiation of HAART and before all changes in drug regimens, combined with phone-in support while on HAART. They considered a moderate-prevalence and a high-prevalence population of MSM.

Results
If the impact of HIV transmission is ignored, the counseling intervention has a cost-effectiveness ratio of $25,500 per quality-adjusted life year (QALY) gained. When HIV transmission is included, the cost-effectiveness ratio is much lower: $7400 and $8700 per QALY gained in the moderate- and high-prevalence populations, respectively. When the intervention is twice as costly per counseling session and half as effective as estimated in the base case (in terms of the number of individuals who become highly adherent, and who remain highly adherent), then the intervention costs $17,100 and $19,600 per QALY gained in the 2 populations, respectively.

Conclusions
Counseling to improve adherence to HAART increased length of life, modestly reduced HIV transmission, and cost substantially less than $50,000 per QALY gained over a wide range of assumptions but did not reduce the proportion of drug-resistant strains. Such counseling provides only modest benefit as a tool for HIV prevention but can provide significant benefit for individual patients at an affordable cost.

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Journal Articles
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Medical Decision Making
Authors
Gregory Zaric
Ahmed Bayoumi
Margaret L. Brandeau
Douglas K. Owens
Douglas Owens
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Nuclear energy production today and in the near future will still be dominated by light-water reactors and therefore there will be a continued need for uranium enrichment. There is currently a focused attention on gas centrifuge enrichment. Gas centrifuge technology is much cheaper and efficient, but also poses a greater security concern, than the former gas diffusion technology.

In order to address the increased security concerns, the International Atomic Energy Agency (IAEA) is planning and implementing strengthened safeguards procedures involving an increased reliance on continuous and remote monitoring technologies, and environmental sampling. The IAEA is also promoting multilateral enrichment centers as an additional avenue to enhance international security. Much of the current enrichment industry today already involves international partnerships such as between the US and European companies, or the tripartite agreement between Russia, China and the IAEA.

In order for safeguards and multilateral approaches to be viable and effective, they need to be accepted by industry, operators, states and the regulatory agencies. This talk will address how strengthened safeguards could be implemented while accommodating potentially conflicting interests such as: the protection of proprietary information, transparency in monitoring, applicability in multilateral arrangements, cost-effectiveness, and the ultimate goal of ensuring that enrichment activities remain peaceful.

Elena Rodriguez-Vieitez is a postdoctoral science fellow at CISAC, Stanford. Her research concerns proliferation risks associated with the global expansion of nuclear power. She received her PhD in nuclear engineering at the University of California, Berkeley. Her dissertation focused on nuclear physics experimental work conducted at cyclotron facilities at the Lawrence Berkeley National Lab and Michigan State University, where she analyzed nuclear structure and fragmentation reaction data of neutron-rich unstable nuclei. As a nuclear engineering graduate student, she collaborated on a Department of Energy research project on radioactive waste transmutation in molten-salt reactors, where she modeled actinide transmutation efficiency and evaluated proliferation and environmental risks. As a graduate student, Rodriguez-Vieitez was also a research associate on public policy and nuclear threats at the University of California Institute on Global Conflict and Cooperation. Prior to her PhD studies, she was an intern at the National Academy of Sciences' Board on Radioactive Waste Management in Washington, DC.

Reuben W. Hills Conference Room

Elena Rodriguez-Vieitez Speaker
Seminars
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Background: A bioterrorism attack with an agent such as anthrax will require rapid deployment of medical and pharmaceutical supplies to exposed individuals. How should such a logistical system be organized? How much capacity should be built into each element of the bioterrorism response supply chain?

Methods: The authors developed a compartmental model to evaluate the costs and benefits of various strategies for preattack stockpiling and postattack distribution and dispensing of medical and pharmaceutical supplies, as well as the benefits of rapid attack detection.

Results: The authors show how the model can be used to address a broad range of logistical questions as well as related, nonlogistical questions (e.g., the cost-effectiveness of strategies to improve patient adherence to antibiotic regimens). They generate several key insights about appropriate strategies for local communities. First, stockpiling large local inventories of medical and pharmaceutical supplies is unlikely to be the most effective means of reducing mortality from an attack, given the availability of national and regional supplies. Instead, communities should create sufficient capacity for dispensing prophylactic antibiotics in the event of a large-scale bioterror attack. Second, improved surveillance systems can significantly reduce deaths from such an attack but only if the local community has sufficient antibiotic-dispensing capacity. Third, mortality from such an attack is significantly affected by the number of unexposed individuals seeking prophylaxis and treatment. Fourth, full adherence to treatment regimens is critical for reducing expected mortality.

Conclusions: Effective preparation for response to potential bioterror attacks can avert deaths in the event of an attack. Models such as this one can help communities more effectively prepare for response to potential bioterror attacks. Key words: bioterror; supply chain; logistics; anthrax; emergency response.

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Publication Type
Journal Articles
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Medical Decision Making
Authors
GS Zaric
Dena M. Bravata
Jon-Erik Holty
Kathryn M. McDonald
Douglas K. Owens
Douglas K. Owens
Margaret L. Brandeau
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BACKGROUND: The availability of human papillomavirus (HPV) DNA testing and vaccination against HPV types 16 and 18 (HPV-16,18) motivates questions about the cost-effectiveness of cervical cancer prevention in the United States for unvaccinated older women and for girls eligible for vaccination. METHODS: An empirically calibrated model was used to assess the quality-adjusted life years (QALYs), lifetime costs, and incremental cost-effectiveness ratios (2004 US dollars per QALY) of screening, vaccination of preadolescent girls, and vaccination combined with screening. Screening varied by initiation age (18, 21, or 25 years), interval (every 1, 2, 3, or 5 years), and test (HPV DNA testing of cervical specimens or cytologic evaluation of cervical cells with a Pap test). Testing strategies included: 1) cytology followed by HPV DNA testing for equivocal cytologic results (cytology with HPV test triage); 2) HPV DNA testing followed by cytology for positive HPV DNA results (HPV test with cytology triage); and 3) combined HPV DNA testing and cytology. Strategies were permitted to switch once at age 25, 30, or 35 years. RESULTS: For unvaccinated women, triennial cytology with HPV test triage, beginning by age 21 years and switching to HPV testing with cytology triage at age 30 years, cost $78,000 per QALY compared with the next best strategy. For girls vaccinated before age 12 years, this same strategy, beginning at age 25 years and switching at age 35 years, cost $41,000 per QALY with screening every 5 years and $188,000 per QALY screening triennially, each compared with the next best strategy. These strategies were more effective and cost-effective than screening women of all ages with cytology alone or cytology with HPV triage annually or biennially. CONCLUSIONS: For both vaccinated and unvaccinated women, age-based screening by use of HPV DNA testing as a triage test for equivocal results in younger women and as a primary screening test in older women is expected to be more cost-effective than current screening recommendations.

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Journal Articles
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Journal of the National Cancer Institute
Authors
Jeremy Goldhaber-Fiebert
Jeremy Goldhaber-Fiebert
Stout NK
Salomon JA
Kuntz KM
Goldie SJ
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OBJECTIVES: To determine whether gaps exist in published cost-utility analyses as measured by their coverage of topics addressed in current HIV guidelines from the Department of Health and Human Services (DHHS).

DESIGN: A systematic review of US-based cost-effectiveness analyses of HIV/AIDS prevention and management strategies, based on original, published research.

METHODS: Predefined criteria were used to identify all analyses pertaining to prevention and management of HIV/AIDS; information was collected on type of strategy, patient demographics, study perspective, quality of the study, effectiveness measures, costs, and cost-effectiveness ratios.

RESULTS: One hundred and six studies were identified; 62 described strategies for averting new HIV infections, and 44 dealt with managing persons who are HIV positive. The quality of studies was generally high, but gaps were found in all studies. Especially common were omissions in reporting data abstraction methodology and discussions of direction and magnitude of potential biases. Among the 22 most highly rated papers (score of 90 or higher), only 1 was cited in the guidelines, and 3 papers reported on interventions that were superseded by newer approaches. Using a USD 100,000 threshold, the guidelines usually endorsed interventions found to be cost-effective. Exceptions included recommending postexposure prophylaxis (PEP) for populations in which PEP is unlikely to be cost-effective and not recommending primary resistance testing in treatment-naive persons, although the intervention was reported to have a cost-effectiveness ratio of less than USD 50,000.

CONCLUSIONS: Despite an abundant literature on the cost-utility of HIV/AIDS-targeted strategies, guidelines cite relatively few of these papers, and gaps exist regarding assessments of some strategies and special populations.

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Journal Articles
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Medical Decision Making
Authors
Hornberger J
Mark Holodniy
Robertus K
Winnike M
Gibson M
Verhulst E
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Background: As many as 10% of Asian and Pacific Islander adults in the United States are chronically infected with hepatitis B virus (HBV), and up to two thirds are unaware that they are infected. Without proper medical management and antiviral therapy, up to 25% of Asian and Pacific Islander persons with chronic HBV infection will die of liver disease.

Objective: To assess the cost-effectiveness of 4 HBV screening and vaccination programs for Asian and Pacific Islander adults in the United States.

Design: Markov model with costs and benefits discounted at 3%.

Data Source: Published literature and expert opinion. TARGET

Population: Asian and Pacific Islander adults (base-case age, 40 years; sensitivity analysis conducted on ages 20 to 60 years).

Time Horizone: Lifetime.

Perspective: U.S. societal.

Interventions: A universal vaccination strategy in which all individuals are given a 3-dose vaccination series; a screen-and-treat strategy, in which individuals are given blood tests to determine whether they are chronically infected, and infected persons are monitored and treated; a screen, treat, and ring vaccinate strategy, in which all individuals are tested for chronic HBV infection and close contacts of infected persons are screened and vaccinated if needed; and a screen, treat, and vaccinate strategy, in which all individuals are tested and then vaccinated with a 3-dose series if needed. In all cases, persons found to be chronically infected are monitored and treated if indicated.

Outcome Measure: Costs (2006 U.S. dollars), quality-adjusted life-years (QALYs), and incremental cost-effectiveness.

Results of Base-case Analysis: Compared with the status quo, the screen-and-treat strategy has an incremental cost-effectiveness ratio of $36,088 per QALY gained. The screen, treat, and ring vaccinate strategy gains more QALYs than the screen and treat strategy and incurs modest incremental costs, leading to incremental cost-effectiveness of $39,903 per QALY gained compared with the screen and treat strategy. The universal vaccination and screen, treat, and vaccinate strategies were weakly dominated by the other 2 strategies.

Results of Sensitivity Analysis: Over a wide range of variables, the incremental cost-effectiveness ratios of the screen and treat and screen, treat, and ring vaccinate strategies were less than $50,000 per QALY gained.

Limitations: Results depend on the accuracy of the underlying data and assumptions. The long-term effectiveness of new and future HBV treatments is uncertain.

Conclusions: Screening programs for HBV among Asian and Pacific Islander adults are likely to be cost effective. Clinically significant benefits accrue from identifying chronically infected persons for medical management and vaccinating their close contacts. Such efforts can greatly reduce the burden of HBV-associated liver cancer and chronic liver disease in the Asian and Pacific Islander population.

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Publication Type
Journal Articles
Publication Date
Journal Publisher
Annals of Internal Medicine
Authors
DW Hutton
D Tan
SK So
Margaret L. Brandeau
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Purpose: One-year adjuvant trastuzumab (AT) therapy, with or without anthracyclines, increases disease-free and overall survival in early-stage HER2/neu-positive breast cancer. We sought to evaluate the cost effectiveness of these regimens, which are expensive and potentially toxic.

Methods: We used a Markov health-state transition model to simulate three adjuvant therapy options for a cohort of 49-year-old women with HER2/neu-positive early-stage breast cancer: conventional chemotherapy without trastuzumab; anthracycline-based AT regimens used in the National Surgical Adjuvant Breast and Bowel Project B-31 and North Central Cancer Treatment Group N9831 trials; and the nonanthracycline AT regimen used in the Breast Cancer International Research group 006 trial. The base case used treatment efficacy measures reported in the randomized clinical trials of AT. We measured health outcomes in quality-adjusted life-years (QALYs) and costs in 2005 United States dollars (US$) and subjected results to probabilistic sensitivity analysis.

Results: In the base case, the anthracycline-based AT arm has an incremental cost-effectiveness ratio (ICER) of $39,982/QALY, whereas the nonanthracycline AT arm is more expensive and less effective; this result is insensitive to changes in recurrence rates, but if there is no benefit after 4 years, ICERs exceed $100,000/QALY for both AT arms. Results are moderately sensitive to variation in breast cancer survival rates and trastuzumab cost, and less sensitive to variations in cardiac toxicity.

Conclusion: AT has an ICER comparable to those for other widely used interventions. Longer clinical follow-up is warranted to evaluate the long-term efficacy and toxicity of different AT regimens.

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Publication Type
Journal Articles
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Journal Publisher
Journal of Clinical Oncology
Authors
AW Kurian
RN Thompson
AF Gaw
S Arai
R Ortiz
Alan Garber
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Background: The comparative effectiveness of coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI) for patients in whom both procedures are feasible remains poorly understood.

Purpose: To compare the effectiveness of PCI and CABG in patients for whom coronary revascularization is clinically indicated.

Data Sources: MEDLINE, EMBASE, and Cochrane databases (1966–2006); conference proceedings; and bibliographies of retrieved articles. Study Selection: Randomized, controlled trials (RCTs) reported in any language that compared clinical outcomes of PCI with those of CABG, and selected observational studies.

Data Extraction: Information was extracted on study design, sample characteristics, interventions, and clinical outcomes.

Data Synthesis: The authors identified 23 RCTs in which 5019 patients were randomly assigned to PCI and 4944 patients were randomly assigned to CABG. The difference in survival after PCI or CABG was less than 1% over 10 years of follow-up. Survival did not differ between PCI and CABG for patients with diabetes in the 6 trials that reported on this subgroup. Procedure-related strokes were more common after CABG than after PCI (1.2% vs. 0.6%; risk difference, 0.6%; P = 0.002). Angina relief was greater after CABG than after PCI, with risk differences ranging from 5% to 8% at 1 to 5 years (P < 0.001). The absolute rates of angina relief at 5 years were 79% after PCI and 84% after CABG. Repeated revascularization was more common after PCI than after CABG (risk difference, 24% at 1 year and 33% at 5 years; P < 0.001); the absolute rates at 5 years were 46.1% after balloon angioplasty, 40.1% after PCI with stents, and 9.8% after CABG. In the observational studies, the CABG–PCI hazard ratio for death favored PCI among patients with the least severe disease and CABG among those with the most severe disease.

Limitations: The RCTs were conducted in leading centers in selected patients. The authors could not assess whether comparative outcomes vary according to clinical factors, such as extent of coronary disease, ejection fraction, or previous procedures. Only 1 small trial used drug-eluting stents.

Conclusion: Compared with PCI, CABG was more effective in relieving angina and led to fewer repeated revascularizations but had a higher risk for procedural stroke. Survival to 10 years was similar for both procedures.

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1
Publication Type
Journal Articles
Publication Date
Journal Publisher
Annals of Internal Medicine
Authors
Dena M. Bravata
Allison Gienger
Kathryn M. McDonald
Vandana Sundaram
MV Perez
R Varghese
JR Kapoor
R Ardehali
Douglas K. Owens
Douglas K. Owens
Mark A. Hlatky
Mark A. Hlatky
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