Biomedical subjects

Gillian D Sanders

Publications and source records attributed to Gillian D Sanders.

At least 19 recordsLinked to original sources

PubMed2007

Effectiveness and cost-effectiveness of thrombolysis in submassive pulmonary embolism.

BACKGROUND: Thrombolytic therapy is controversial in patients with submassive pulmonary embolism. METHODS: We performed a cost-effectiveness analysis to compare health effects and costs of treatment with alteplase plus heparin sodium vs heparin alone in hemodynamically stable patients with pulmonary embolism and right ventricular dysfunction by developing a Markov model and using data from clinical trials and administrative sources. RESULTS: Based on data from a recent randomized trial, we assumed that the risk of clinical deterioration requiring treatment escalation was almost 3 times higher in patients who received heparin alone (23.2% vs 7.6%) but that the risk of death was equal in the 2 cohorts (2.7%). Based on registry data, we assumed that the risk of intracranial hemorrhage was approximately 3 times higher in patients who received alteplase plus heparin (1.2% vs 0.4%). Under these and other assumptions, thrombolysis resulted in marginally higher total lifetime health care costs ($43,900 vs $43,300) and was slightly less effective (10.52 vs 10.57 quality-adjusted life-years) than treatment with heparin alone. Thrombolysis was more effective and cost less than $50,000 per quality-adjusted life-year gained when we assumed that the baseline risk of death in the heparin group was 3 times the base-case value (8.1%) and that alteplase reduced the relative risk of death by at least 10%. CONCLUSIONS: Available data do not support the routine use of thrombolysis to treat patients with submassive pulmonary embolism. However, thrombolysis may prove to be cost-effective in selected subgroups of hemodynamically stable patients in whom the risk of death is higher.

Cost-Benefit Analysis↗

PubMed2006

Effectiveness and cost-effectiveness of strategies to expand antiretroviral therapy in St. Petersburg, Russia.

OBJECTIVE: To assess the effectiveness and cost-effectiveness of treating HIV-infected injection drug users (IDUs) and non-IDUs in Russia with highly active antiretroviral therapy HAART. DESIGN AND METHODS: A dynamic HIV epidemic model was developed for a population of IDUs and non-IDUs. The location for the study was St. Petersburg, Russia. The adult population aged 15 to 49 years was subdivided on the basis of injection drug use and HIV status. HIV treatment targeted to IDUs and non-IDUs, and untargeted treatment interventions were considered. Health care costs and quality-adjusted life years (QALYs) experienced in the population were measured, and HIV prevalence, HIV infections averted, and incremental cost-effectiveness ratios of different HAART strategies were calculated. RESULTS: With no incremental HAART programs, HIV prevalence reached 64% among IDUs and 1.7% among non-IDUs after 20 years. If treatment were targeted to IDUs, over 40 000 infections would be prevented (75% among non-IDUs), adding 650 000 QALYs at a cost of USD 1501 per QALY gained. If treatment were targeted to non-IDUs, fewer than 10 000 infections would be prevented, adding 400 000 QALYs at a cost of USD 2572 per QALY gained. Untargeted strategies prevented the most infections, adding 950 000 QALYs at a cost of USD 1827 per QALY gained. Our results were sensitive to HIV transmission parameters. CONCLUSIONS: Expanded use of antiretroviral therapy in St. Petersburg, Russia would generate enormous population-wide health benefits and be economically efficient. Exclusively treating non-IDUs provided the least health benefit, and was the least economically efficient. Our findings highlight the urgency of initiating HAART for both IDUs and non-IDUs in Russia.

Adolescent↗

PubMed2006

Cost-effectiveness as an outcome in randomized clinical trials.

BACKGROUND: Economic outcomes are now included in many contemporary randomized trials and provide an additional dimension to the assessment of interventions. Economic data collection and analysis pose several methodologic challenges, however. PURPOSE: This paper reviews methods of incorporating economic outcomes in clinical trials. RESULTS: Data on medical resource utilization and cost can readily be collected along with data on clinical outcomes. The cost of planned interventions can be measured with reasonable accuracy, but costs due to unplanned clinical events are more difficult to measure reliably. The total cost depends critically on these relatively infrequent, yet costly, adverse outcomes, which may partially, or even completely, offset any difference between the planned costs of the randomized therapies. Newer therapies are typically more expensive than older therapies, so the most important question is whether patient outcomes are improved sufficiently to justify the added expense. Cost-effectiveness analysis helps gauge the value provided by a new therapy. The cost-effectiveness of an intervention compared with an alternative is defined as the ratio of the incremental costs and the incremental clinical benefits, measured as dollars per quality-adjusted life-year added. The follow-up period in most clinical trials is generally long enough to measure the added cost of therapy, but may not capture the full benefits of treatment. The limited time horizon of clinical trials makes it necessary to use a model to extrapolate the observed effect of treatment and project the increase in life expectancy. The resulting cost-effectiveness ratio is sensitive to assumptions about the long-term efficacy of treatment, particularly whether the treatment effect will continue or dissipate over time. CONCLUSION: Economic outcomes can be measured alongside clinical outcomes in randomized trial. While the use of cost-effectiveness models falls outside the strictly empirical, within-trial analysis framework that is embraced by most clinical trialists, it provides an explicit approach to assessing whether the intervention under study provides a clinically meaningful improvement in outcome that is worthwhile.

Clinical Protocols↗

PubMed2005

Cost-effectiveness of implantable cardioverter-defibrillators.

BACKGROUND: Eight randomized trials have evaluated whether the prophylactic use of an implantable cardioverter-defibrillator (ICD) improves survival among patients who are at risk for sudden death due to left ventricular systolic dysfunction but who have not had a life-threatening ventricular arrhythmia. We assessed the cost-effectiveness of the ICD in the populations represented in these primary-prevention trials. METHODS: We developed a Markov model of the cost, quality of life, survival, and incremental cost-effectiveness of the prophylactic implantation of an ICD, as compared with control therapy, among patients with survival and mortality rates similar to those in each of the clinical trials. We modeled the efficacy of the ICD as a reduction in the relative risk of death on the basis of the hazard ratios reported in the individual clinical trials. RESULTS: Use of the ICD increased lifetime costs in every trial. Two trials--the Coronary Artery Bypass Graft (CABG) Patch Trial and the Defibrillator in Acute Myocardial Infarction Trial (DINAMIT)--found that the prophylactic implantation of an ICD did not reduce the risk of death and thus was both more expensive and less effective than control therapy. For the other six trials--the Multicenter Automatic Defibrillator Implantation Trial (MADIT) I, MADIT II, the Multicenter Unsustained Tachycardia Trial (MUSTT), the Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE) trial, the Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure (COMPANION) trial, and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT)--the use of an ICD was projected to add between 1.01 and 2.99 quality-adjusted life-years (QALY) and between 68,300 dollars and 101,500 dollars in cost. Using base-case assumptions, we found that the cost-effectiveness of the ICD as compared with control therapy in these six populations ranged from 34,000 dollars to 70,200 dollars per QALY gained. Sensitivity analyses showed that this cost-effectiveness ratio would remain below 100,000 dollars per QALY as long as the ICD reduced mortality for seven or more years. CONCLUSIONS: Prophylactic implantation of an ICD has a cost-effectiveness ratio below 100,000 dollars per QALY gained in populations in which a significant device-related reduction in mortality has been demonstrated.

Cost-Benefit Analysis↗

PubMed2005

Cost-effectiveness of defending against bioterrorism: a comparison of vaccination and antibiotic prophylaxis against anthrax.

BACKGROUND: Weaponized Bacillus anthracis is one of the few biological agents that can cause death and disease in sufficient numbers to devastate an urban setting. OBJECTIVE: To evaluate the cost-effectiveness of strategies for prophylaxis and treatment of an aerosolized B. anthracis bioterror attack. DESIGN: Decision analytic model. DATA SOURCES: We derived probabilities of anthrax exposure, vaccine and treatment characteristics, and their costs and associated clinical outcomes from the medical literature and bioterrorism-preparedness experts. TARGET POPULATION: Persons living and working in a large metropolitan U.S. city. TIME HORIZON: Patient lifetime. PERSPECTIVE: Societal. INTERVENTION: We evaluated 4 postattack strategies: no prophylaxis, vaccination alone, antibiotic prophylaxis alone, or vaccination and antibiotic prophylaxis, as well as preattack vaccination versus no vaccination. OUTCOME MEASURES: Costs, quality-adjusted life-years, life-years, and incremental cost-effectiveness. RESULTS OF BASE-CASE ANALYSIS: If an aerosolized B. anthracis bioweapon attack occurs, postexposure prophylactic vaccination and antibiotic therapy for those potentially exposed is the most effective (0.33 life-year gained per person) and least costly (355 dollars saved per person) strategy, as compared with vaccination alone. At low baseline probabilities of attack and exposure, mass previous vaccination of a metropolitan population is more costly (815 million dollars for a city of 5 million people) and not more effective than no vaccination. RESULTS OF SENSITIVITY ANALYSIS: If prophylactic antibiotics cannot be promptly distributed after exposure, previous vaccination may become cost-effective. LIMITATIONS: The probability of exposure and disease critically depends on the probability and mechanism of bioweapon release. CONCLUSIONS: In the event of an aerosolized B. anthracis bioweapon attack over an unvaccinated metropolitan U.S. population, postattack prophylactic vaccination and antibiotic therapy is the most effective and least expensive strategy.

Anthrax↗

PubMed2005

Cost-effectiveness of screening for HIV in the era of highly active antiretroviral therapy.

BACKGROUND: The costs, benefits, and cost-effectiveness of screening for human immunodeficiency virus (HIV) in health care settings during the era of highly active antiretroviral therapy (HAART) have not been determined. METHODS: We developed a Markov model of costs, quality of life, and survival associated with an HIV-screening program as compared with current practice. In both strategies, symptomatic patients were identified through symptom-based case finding. Identified patients started treatment when their CD4 count dropped to 350 cells per cubic millimeter. Disease progression was defined on the basis of CD4 levels and viral load. The likelihood of sexual transmission was based on viral load, knowledge of HIV status, and efficacy of counseling. RESULTS: Given a 1 percent prevalence of unidentified HIV infection, screening increased life expectancy by 5.48 days, or 4.70 quality-adjusted days, at an estimated cost of 194 dollars per screened patient, for a cost-effectiveness ratio of 15,078 dollars per quality-adjusted life-year. Screening cost less than 50,000 dollars per quality-adjusted life-year if the prevalence of unidentified HIV infection exceeded 0.05 percent. Excluding HIV transmission, the cost-effectiveness of screening was 41,736 dollars per quality-adjusted life-year. Screening every five years, as compared with a one-time screening program, cost 57,138 dollars per quality-adjusted life-year, but was more attractive in settings with a high incidence of infection. Our results were sensitive to the efficacy of behavior modification, the benefit of early identification and therapy, and the prevalence and incidence of HIV infection. CONCLUSIONS: The cost-effectiveness of routine HIV screening in health care settings, even in relatively low-prevalence populations, is similar to that of commonly accepted interventions, and such programs should be expanded.

Adult↗

PubMed2005

Implantable cardioverter defibrillators and cardiac resynchronization therapy in patients with left ventricular dysfunction: randomized trial evidence through 2004.

Although many studies have shown that implantable cardioverter defibrillator (ICD) therapy improves the survival of patients with significant left ventricular dysfunction, the magnitude of effectiveness of ICD therapy in clinically defined subgroups remains uncertain. Similarly, although studies have shown an improvement in patients' hemodynamics and quality of life with cardiac resynchronization therapy (CRT), there is a continuing uncertainty about the effect of CRT on patients' survival and the magnitude of improvement in quality of life with this therapy. On August 24, 2004, an ad hoc group of experts representing clinical cardiovascular medicine, biostatistics, economics, and health policy were joined by representatives of the Food and Drug Administration, Centers for Medicare and Medicaid Services (Baltimore, Md), Agency for Healthcare Research and Quality (Rockville, Md), and the device industry for a 1-day round table to review the available clinical trial evidence on the effect of ICD therapy in the primary prevention of sudden cardiac death and the effect of CRT in patients with congestive heart failure. The meeting was organized by the Duke Clinical Research Institute, Durham, NC, and funded in part by the Agency for Healthcare Research and Quality. This document summarizes the evidence reviewed at that meeting and the discussions of that evidence.

Death, Sudden, Cardiac↗

PubMed2004

Cost-effectiveness of testing for hypercoagulability and effects on treatment strategies in patients with deep vein thrombosis.

PURPOSE: Among patients with deep vein thrombosis, hypercoagulable conditions impart a substantial risk of recurrent thrombosis. We sought to determine the cost-effectiveness of testing for these disorders, as well as which tests should be selected and how results should be used. METHODS: Using a Markov state-transition model, strategies of testing or not testing for a hypercoagulable state followed by anticoagulation for 6 to 36 months were compared in a hypothetical cohort of patients with apparently idiopathic deep vein thrombosis who were followed for life. Strategies were compared based on lifetime costs, quality-adjusted life-years (QALYs), and marginal cost-effectiveness. RESULTS: In the base case, testing followed by 24 months of anticoagulation in patients with a hypercoagulable condition was more cost-effective ($54,820; 23.76 QALYs) than usual care, which comprised 6 months of anticoagulation without testing ($55,260; 23.72 QALYs). All hypercoagulable conditions tested were common enough and associated with a sufficient risk of recurrence to justify inclusion in a test panel. Twenty-four months of initial anticoagulation was preferred (<$50,000/QALY) for most conditions, whereas lifetime anticoagulation was preferred for patients with antiphospholipid antibody syndrome ($2928/QALY) or homozygous factor V Leiden mutation ($3804/QALY). Models using newer evidence on recurrence suggested 18 to 36 months of anticoagulation without testing as the preferred approach. CONCLUSION: Testing for hypercoagulable disorders in patients with idiopathic deep vein thrombosis followed by 2 years of anticoagulation in affected patients is cost-effective. A simpler approach of treating all patients with prolonged anticoagulation without testing is justified if data confirm the persistent risk of recurrent thrombosis.

Aged↗

PubMed2004

Cost-effectiveness of photodynamic therapy for high-grade dysplasia in Barrett's esophagus.

BACKGROUND: Photodynamic therapy appears to be effective in ablating high-grade dysplasia in Barrett's esophagus. Our aim was to identify the most effective and cost-effective strategy for managing high-grade dysplasia in Barrett's esophagus without associated endoscopically visible abnormalities. METHODS: By using decision analysis, the lifetime costs and benefits of 4 strategies for which long-term data exist were estimated by us: esophagectomy, endoscopic surveillance, photodynamic therapy, followed by esophagectomy for residual high-grade dysplasia; and photodynamic therapy followed by endoscopic surveillance for residual high-grade dysplasia. It was assumed by us that there was a 30% prevalence of cancer in high-grade dysplasia patients and a 77% efficacy of photodynamic therapy for high-grade dysplasia and early cancer. RESULTS: Esophagectomy cost 24,045 dollars, with life expectancy of 11.82 quality-adjusted life years. In comparison, photodynamic therapy followed by surveillance for residual high-grade dysplasia was the most effective strategy, with a quality-adjusted life expectancy of 12.31 quality-adjusted life years, but it also incurred the greatest lifetime cost (47,310 dollars) for an incremental cost-effectiveness of 47,410 dollars/quality-adjusted life years. The results were sensitive to post-surgical quality of life and survival, and to cancer prevalence if photodynamic therapy efficacy for cancer was less than 50%. CONCLUSIONS: Photodynamic therapy followed by endoscopic surveillance for residual high-grade dysplasia appears to be cost effective compared with esophagectomy for patients diagnosed with high-grade dysplasia in Barrett's esophagus. Clinical trials directly comparing these strategies are warranted.

Adenocarcinoma↗

PubMed2004

Evaluating human papillomavirus vaccination programs.

Human papillomavirus (HPV) has been implicated as the primary etiologic agent of cervical cancer. Potential vaccines against high-risk HPV types are in clinical trials. We evaluated vaccination programs with a vaccine against HPV-16 and HPV-18. We developed disease transmission models that estimated HPV prevalence and infection rates for the population overall, by age group, by level of sexual activity within each age group, and by sex. Data were based on clinical trials and published and unpublished sources. An HPV-16/18 vaccine for 12-year-old girls would reduce cohort cervical cancer cases by 61.8%, with a cost-effectiveness ratio of 14,583 dollars per quality-adjusted life year (QALY). Including male participants in a vaccine rollout would further reduce cervical cancer cases by 2.2% at an incremental cost-effectiveness ratio of 442,039 dollars/QALY compared to female-only vaccination. Vaccination against HPV-16 and HPV-18 can be cost-effective, although including male participants in a vaccination program is generally not cost-effective, compared to female-only vaccination.

Adolescent↗

PubMed2003

Decision science and cervical cancer.

Mathematical modeling is an effective tool for guiding cervical cancer screening, diagnosis, and treatment decisions for patients and policymakers. This article describes the use of mathematical modeling as outlined in five presentations from the Decision Science and Cervical Cancer session of the Second International Conference on Cervical Cancer held at The University of Texas M. D. Anderson Cancer Center, April 11-14, 2002. The authors provide an overview of mathematical modeling, especially decision analysis and cost-effectiveness analysis, and examples of how it can be used for clinical decision making regarding the prevention, diagnosis, and treatment of cervical cancer. Included are applications as well as theory regarding decision science and cervical cancer. Mathematical modeling can answer such questions as the optimal frequency for screening, the optimal age to stop screening, and the optimal way to diagnose cervical cancer. Results from one mathematical model demonstrated that a vaccine against high-risk strains of human papillomavirus was a cost-effective use of resources, and discussion of another model demonstrated the importance of collecting direct non-health care costs and time costs for cost-effectiveness analysis. Research presented indicated that care must be taken when applying the results of population-wide, cost-effectiveness analyses to reduce health disparities. Mathematical modeling can encompass a variety of theoretical and applied issues regarding decision science and cervical cancer. The ultimate objective of using decision-analytic and cost-effectiveness models is to identify ways to improve women's health at an economically reasonable cost.

Cost-Benefit Analysis↗

PubMed2003

Cost-effectiveness of alternative management strategies for patients with solitary pulmonary nodules.

BACKGROUND: Positron emission tomography (PET) with 18-fluorodeoxyglucose (FDG) is a potentially useful but expensive test to diagnose solitary pulmonary nodules. OBJECTIVE: To evaluate the cost-effectiveness of strategies for pulmonary nodule diagnosis and to specifically compare strategies that did and did not include FDG-PET. DESIGN: Decision model. DATA SOURCES: Accuracy and complications of diagnostic tests were estimated by using meta-analysis and literature review. Modeled survival was based on data from a large tumor registry. Cost estimates were derived from Medicare reimbursement and other sources. TARGET POPULATION: All adult patients with a new, noncalcified pulmonary nodule seen on chest radiograph. TIME HORIZON: Patient lifetime. PERSPECTIVE: Societal. INTERVENTION: 40 clinically plausible combinations of 5 diagnostic interventions, including computed tomography, FDG-PET, transthoracic needle biopsy, surgery, and watchful waiting. OUTCOME MEASURES: Costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. RESULTS OF BASE-CASE ANALYSIS: The cost-effectiveness of strategies depended critically on the pretest probability of malignancy. For patients with low pretest probability (26%), strategies that used FDG-PET selectively when computed tomography results were possibly malignant cost as little as 20 000 dollars per QALY gained. For patients with high pretest probability (79%), strategies that used FDG-PET selectively when computed tomography results were benign cost as little as 16 000 dollars per QALY gained. For patients with intermediate pretest probability (55%), FDG-PET strategies cost more than 220 000 dollars per QALY gained because they were more costly but only marginally more effective than computed tomography-based strategies. RESULTS OF SENSITIVITY ANALYSIS: The choice of strategy also depended on the risk for surgical complications, the probability of nondiagnostic needle biopsy, the sensitivity of computed tomography, and patient preferences for time spent in watchful waiting. In probabilistic sensitivity analysis, FDG-PET strategies were cost saving or cost less than 100 000 dollars per QALY gained in 76.7%, 24.4%, and 99.9% of computer simulations for patients with low, intermediate, and high pretest probability, respectively. CONCLUSIONS: FDG-PET should be used selectively when pretest probability and computed tomography findings are discordant or in patients with intermediate pretest probability who are at high risk for surgical complications. In most other circumstances, computed tomography-based strategies result in similar quality-adjusted life-years and lower costs.

Algorithms↗

PubMed2003

Cost-effectiveness of recombinant human activated protein C and the influence of severity of illness in the treatment of patients with severe sepsis.

PURPOSE: To evaluate the cost-effectiveness of recombinant human activated protein C (rhAPC) compared with usual therapy for patients with severe sepsis, and also to determine the influence that severity of illness exerts on cost-effectiveness. MATERIALS AND METHODS: We use a Markov model-based cost-effectiveness analysis of treatment strategies for patients with severe sepsis. Therapy includes treatment with either rhAPC and usual therapy, or usual therapy alone. Probabilities for clinical outcomes were obtained from a large randomized clinical trial comparing the use of rhAPC with placebo (PROWESS study) and from outcomes literature for patients with severe sepsis and its complications. Cost estimates were based on Medicare reimbursement rates, Health Care Financing Administration information and the literature. Outcome measures include life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness. RESULTS: Compared with usual therapy alone, rhAPC treatment for patients with very severe sepsis (APACHE II score > or = 25) was associated with an incremental cost-effectiveness ratio of $13 493/QALY. Treatment of patients with less severe sepsis with rhAPC (APACHE II score < 25) had an incremental cost-effectiveness ratio of $403,000/QALY. For patients with very severe sepsis the incremental cost-effectiveness ratio for treatment with rhAPC remained under $30,000/QALY, over a broad range of variables, including costs of rhAPC, costs of acute care and costs and probabilities of complications of treatment. For patients with less severe sepsis, drug costs would need to fall well below current market price before achieving cost-effectiveness. A probabilistic sensitivity analysis comparing rhAPC treatment with usual therapy for patients with very severe sepsis showed that < 1% of Monte Carlo simulations had incremental cost-effectiveness ratios > $50,000/QALY. CONCLUSIONS: The use of rhAPC for the treatment of patients with very severe sepsis, as determined by APACHE II score > or = 25, appears cost-effective, while treatment of patients with APACHE II score < 25 is not cost-effective.

APACHE↗

PubMed2003

Cost-effectiveness of the implantable cardioverter defibrillator.

Many clinicians and policymakers are concerned whether use of the implantable defibrillator (ICD) is justified in view of its high cost. Three randomized trials of the ICD have reported economic outcomes. Each trial found a large difference in cost between patients assigned to an ICD versus patients assigned to conventional therapy that persisted over three to six years of follow-up. Each trial also found better survival among ICD patients, and calculated ICD cost-effectiveness (CE) ratios between 27,000 dollars per life year added and 139,000 dollars per life year added. The variability in the cost-effectiveness ratios among trials is mainly due to variability in the years of life added by the ICD among the trials and, by extension, among patient subgroups. A rough rule of thumb is that the ICD will be economically attractive when it prolongs mean survival by six months or more, which is attainable in higher risk patient subgroups.

Cost-Benefit Analysis↗

PubMed2003

Cost-effectiveness of a potential vaccine for human papillomavirus.

Human papillomavirus (HPV) infection, usually a sexually transmitted disease, is a risk factor for cervical cancer. Given the substantial disease and death associated with HPV and cervical cancer, development of a prophylactic HPV vaccine is a public health priority. We evaluated the cost-effectiveness of vaccinating adolescent girls for high-risk HPV infections relative to current practice. A vaccine with a 75% probability of immunity against high-risk HPV infection resulted in a life-expectancy gain of 2.8 days or 4.0 quality-adjusted life days at a cost of $246 relative to current practice (incremental cost effectiveness of $22,755/quality-adjusted life year [QALY]). If all 12-year-old girls currently living in the United States were vaccinated, >1,300 deaths from cervical cancer would be averted during their lifetimes. Vaccination of girls against high-risk HPV is relatively cost effective even when vaccine efficacy is low. If the vaccine efficacy rate is 35%, the cost effectiveness increases to $52,398/QALY. Although gains in life expectancy may be modest at the individual level, population benefits are substantial.

Child↗

PubMed2002

Evidence-based practice for mere mortals: the role of informatics and health services research.

The poor translation of evidence into practice is a well-known problem. Hopes are high that information technology can help make evidence-based practice feasible for mere mortal physicians. In this paper, we draw upon the methods and perspectives of clinical practice, medical informatics, and health services research to analyze the gap between evidence and action, and to argue that computing systems for bridging this gap should incorporate both informatics and health services research expertise. We discuss 2 illustrative systems--trial banks and a web-based system to develop and disseminate evidence-based guidelines (alchemist)--and conclude with a research and training agenda.

Evidence-Based Medicine↗

PubMed2002

Effect of risk stratification on cost-effectiveness of the implantable cardioverter defibrillator.

BACKGROUND: Implantable cardioverter defibrillators (ICDs) effectively prevent sudden cardiac death, but selection of appropriate patients for implantation is complex. We evaluated whether risk stratification based on risk of sudden cardiac death alone was sufficient to predict the effectiveness and cost-effectiveness of the ICD. METHODS: We developed a Markov model to evaluate the cost-effectiveness of ICD implantation compared with empiric amiodarone treatment. The model incorporated mortality rates from sudden and nonsudden cardiac death, noncardiac death and costs for each treatment strategy. We based our model inputs on data from randomized clinical trials, registries, and meta-analyses. We assumed that the ICD reduced total mortality rates by 25%, relative to use of amiodarone. RESULTS: The relationship between cost-effectiveness of the ICD and the total annual cardiac mortality rate is U-shaped; cost-effectiveness becomes unfavorable at both low and high total cardiac mortality rates. If the annual total cardiac mortality rate is 12%, the cost-effectiveness of the ICD varies from $36,000 per quality-adjusted life-year (QALY) gained when the ratio of sudden cardiac death to nonsudden cardiac death is 4 to $116,000 per QALY gained when the ratio is 0.25. CONCLUSIONS: The cost-effectiveness of ICD use relative to amiodarone depends on total cardiac mortality rates as well as the ratio of sudden to nonsudden cardiac death. Studies of candidate diagnostic tests for risk stratification should distinguish patients who die suddenly from those who die nonsuddenly, not just patients who die suddenly from those who live.

Amiodarone↗

PubMed2002

Perinatal screening for group B streptococci: cost-benefit analysis of rapid polymerase chain reaction.

OBJECTIVE: To evaluate the costs and benefits of a group B streptococci screening strategy using a new, rapid polymerase chain reaction test in a hypothetical cohort of expectant mothers in the United States. METHODS DESIGN: Cost-benefit analysis using the human capital method. We developed a decision model to analyze the costs and benefits of a hypothetical group B streptococci screening strategy using a new, rapid polymerase chain reaction test as compared with the currently recommended group B streptococci screening guidelines-prenatal culture performed at 35 to 37 weeks or risk-factor-based strategy with subsequent intrapartum treatment of the expectant mothers with antibiotics to prevent early-onset group B streptococcal infections in their infants. PARTICIPANTS: A hypothetical cohort of pregnant women and their newborns. INTERVENTIONS: Screening strategies for group B streptococci using the new polymerase chain reaction technique, the 35- to 37-week culture, or maternal risk factors. OUTCOME MEASURES: Infant infections averted, infant deaths, infant disabilities, costs, and societal benefits of healthy infants. RESULTS: A screening strategy using the new polymerase chain reaction test generates a net benefit of $7 per birth when compared with the maternal risk-factor strategy. For every 1 million births, 80 700 more women would receive antibiotics, 884 fewer infants would become infected with early-onset group B streptococci, and 23 infants would be saved from death or disability. The polymerase chain reaction-based strategy generates a net benefit of $6 per birth when compared with the 35- to 37-week prenatal culture strategy and results in fewer maternal courses of antibiotics (64 080 per million births), fewer perinatal infections with early-onset group B streptococci (218/million), and a reduction in 6 infant deaths and severe infant disability per million births. The benefits hold over a wide range of assumptions regarding key factors in the analysis. CONCLUSIONS: Although additional clinical trials are needed to establish the accuracy of this new polymerase chain reaction test, initial studies suggest that strategies using this test will be superior to the other 2 strategies. Using the rapid polymerase chain reaction test becomes less attractive as the cost of the test increases. The test's greatest strengths lie in its ability to identify women and infants at risk at the time of labor, thereby decreasing the number of false-positives and false-negatives seen with the other 2 strategies and allowing for more accurate and effective intrapartum prophylaxis.

Cost-Benefit Analysis↗