A probabilistic cost-effectiveness analysis of enoxaparin versus unfractionated heparin for the prophylaxis of deep-vein thrombosis following major trauma.

BACKGROUND: In the absence of major contraindications, treatment guidelines recommend that, following a major traumatic event, all patients receive low molecular weight heparin (e.g. enoxaparin) as thromboprophylaxis for the prevention of deep vein thrombosis (DVT). OBJECTIVE: To estimate the incremental cost-effectiveness of enoxaparin versus low dose unfractionated heparin (UH) for the prophylaxis of DVT following major trauma. METHODS: Using probabilistic decision-analytic modeling, we estimated the incremental cost-effectiveness of enoxaparin versus unfractionated heparin for the prophylaxis of DVT following moderate to severe trauma (injury severity score > or = 9) over a life-time time horizon from the perspective of the health care payer. Cost effectiveness was calculated based on both the incremental cost (DeltaC) per DVT averted and the DeltaC per life year gained (LYG). RESULTS: The incremental cost of enoxaparin relative to UH was C$90, and the incremental effectiveness was 0.085 DVTs averted and -0.13 LYG. This resulted in an incremental cost-effectiveness ratio of C$1,059 per DVT averted, and the conclusion that UH is the dominant strategy in terms of LYG. In addition to the probabilistic analysis, one-way and two-way sensitivity analysis revealed that the model was most sensitive to variation in the discount rate (3% - 7%), but that UH remained the dominant strategy in terms of life years independent of the parameter estimates. CONCLUSIONS: Although enoxaparin appears to be a cost-effective alternative when considering the intermediate endpoint of DVTs averted, it may be dominated by UH in terms of LYG due to the higher incidence of major bleeds in patients receiving enoxaparin versus UH.

A probabilistic cost-effectiveness analysis of enoxaparin versus unfractionated heparin for the prophylaxis of deep-vein thrombosis following major trauma.

BACKGROUND: In the absence of major contraindications, treatment guidelines recommend that, following a major traumatic event, all patients receive low molecular weight heparin (e.g. enoxaparin) as thromboprophylaxis for the prevention of deep vein thrombosis (DVT). OBJECTIVE: To estimate the incremental cost-effectiveness of enoxaparin versus low dose unfractionated heparin (UH) for the prophylaxis of DVT following major trauma. METHODS: Using probabilistic decision-analytic modeling, we estimated the incremental cost-effectiveness of enoxaparin versus unfractionated heparin for the prophylaxis of DVT following moderate to severe trauma (injury severity score > or = 9) over a life-time time horizon from the perspective of the health care payer. Cost effectiveness was calculated based on both the incremental cost (ïC) per DVT averted and the ïC per life year gained (LYG). RESULTS: The incremental cost of enoxaparin relative to UH was C$90, and the incremental effectiveness was 0.085 DVTs averted and -0.13 LYG. This resulted in an incremental cost-effectiveness ratio of C$1,059 per DVT averted, and the conclusion that UH is the dominant strategy in terms of LYG. In addition to the probabilistic analysis, one-way and two-way sensitivity analysis revealed that the model was most sensitive to variation in the discount rate (3-7%), but that UH remained the dominant strategy in terms of life years independent of the parameter estimates. CONCLUSIONS: Although enoxaparin appears to be a cost-effective alternative when considering the intermediate endpoint of DVTs averted, it may be dominated by UH in terms of LYG due to the higher incidence of major bleeds in patients receiving enoxaparin versus UH.

Retrospective economic evaluation of a controlled trial of indomethacin prophylaxis for patent ductus arteriosus in premature infants.

OBJECTIVE: To determine the incremental cost-effectiveness of indomethacin prophylaxis in extremely low birth weight infants enrolled in the Trial of Indomethacin Prophylaxis in Preterms (TIPP). STUDY DESIGN: Participants in this economic evaluation were 428 infants enrolled at 9 Canadian TIPP centres. The study took a third-party payer perspective. Prior to the analysis of clinical trial data, direct medical costs were derived from chart review of 89 items of resource utilization, for each day from admission to hospital discharge. Unit costs for each resource were obtained from a provincially standardized cost-accounting system. Incremental cost-effectiveness analysis was performed, with estimation of cost-effectiveness acceptability curves through non-parametric bootstrapping. RESULTS: The mean (SD) cost was $68,279 (40,317) for the placebo group and $69,629 (37,989) for the indomethacin group. Indomethacin prophylaxis cost an additional $67,500 per death or impairment averted. However, the precision of this estimate was low, such that the probability that the estimate was lower than $300,000 per death or impairment averted was only 61%. The results were similar when surgical costs were assumed to be 500% of those measured in the trial. CONCLUSIONS: This study does not provide an economic rationale for the use of indomethacin prophylaxis in ELBW infants.

Antiviral agents for influenza: a comparison of cost-effectiveness data.

The economic burden of influenza-related illness has been estimated to be 71.3-166 billion US dollars in the US, the majority of which is attributable to indirect costs as a result of lost productivity. There are currently four antiviral drugs available for the treatment of influenza: two ion channel blockers, amantadine and rimantadine; and two neuraminidase inhibitors, zanamivir and oseltamivir. The objective of this paper was to review the studies evaluating the cost effectiveness of currently available antiviral treatment and prophylaxis management strategies for influenza. Published studies that reported both costs and effectiveness of influenza management were extracted using MEDLINE, pre-MEDLINE and EMBASE. To facilitate a broad comparison, all costs were inflated to 2003 US dollars. Fifteen studies met the inclusion criteria of the review, with 14 analyses based on decision-analytic modelling and one economic analysis performed alongside a clinical trial. Management strategies included antiviral influenza prophylaxis or vaccination, empiric treatment of suspected disease, or antiviral treatment following rapid influenza testing. Study populations included healthy adults, adults at risk of influenza-related adverse outcomes, institutionalised and non-institutionalised elderly, and children. The comparator in all studies was standard care (i.e. over-the-counter medications only), and analyses were carried out from both the societal and payer perspectives. The only dominant strategy relative to standard care was vaccination of the institutionalised elderly. All other strategies in all populations were both more costly and more effective than standard care. Depending on the population and the perspective, the incremental cost-effectiveness ratios (ICERs) for antiviral treatment strategies ranged from 5000 US dollars/QALY for amantadine in test-and-treat studies to >400,000 US dollars/QALY for zanamivir or oseltamivir treatment in children. Sensitivity analysis in all studies consistently reported a strong influence of the population prevalence or diagnostic accuracy of influenza on the cost effectiveness of all strategies. Baseline influenza prevalence varied widely between studies, ranging from 15% to 68%. There was also a wide variation in the assumption about the disutility of influenza (ranging from -0.137 to -0.983 for the elderly requiring hospitalisation), which also impacted the cost effectiveness. Given the variation in the ICERs of antiviral treatment and prophylaxis, the uncertainty around many model parameters, and the dynamic nature of influenza from year to year, one can only conclude that antiviral treatment or prophylaxis for influenza is likely to be more cost effective in specific populations at specific times during the influenza season, and during influenza seasons when the population prevalence reaches epidemic levels or there is mismatch between the vaccine and the circulating virus.

The impact of reference pricing of nonsteroidal anti-inflammatory agents on the use and costs of analgesic drugs.

OBJECTIVE: To estimate the effect of reference pricing (RP) of nonsteroidal anti-inflammatory drugs (NSAIDs) on drug subsidy program and beneficiary expenditures on analgesic drugs. DATA SOURCES/STUDY SETTING: Monthly claims data from Pharmacare, the public drug subsidy program for seniors in British Columbia, Canada, over the period of February 1993 to June 2001. STUDY DESIGN: RP limits drug plan reimbursement of interchangeable medicines to a reference price, which is typically equal to the price of the lowest cost interchangeable drug; any cost above that is borne by the patient. Pharmacare introduced two different forms of RP to the NSAIDs, Type 1 in April 1994 and Type 2 in November 1995. Under Type 1 RP, generic and brand versions of the same NSAID are considered interchangeable, whereas under Type 2 RP different NSAIDs are considered interchangeable. We extrapolated average reimbursement per day of NSAID therapy over the months before RP to estimate what expenditures would have been without the policies. These counterfactual predictions were compared with actual values to estimate the impact of the policies; the estimated impacts on reimbursement rates were multiplied by the postpolicy volume of NSAIDS dispensed, which appeared unaffected by the policies, to estimate expenditure changes. PRINCIPAL FINDINGS: After Type 2 RP, program expenditures declined by $22.7 million (CAN), or $4 million (CAN), annually cutting expenditure by about half. Most savings accrued from the substitution of low-cost NSAIDs for more costly alternatives. About 20 percent of savings represented expenditures by seniors who elected to pay for partially reimbursed drugs. Type 1 RP produced one-quarter the savings of type 2 RP. CONCLUSIONS: Type 2 RP of NSAIDs achieved its goal of reducing drug expenditures and was more effective than Type 1 RP. The effects of RP on patient health and associated health care costs remain to be investigated.

Conducting economic evaluations alongside multinational clinical trials: toward a research consensus.

Demand for economic evaluations in multinational clinical trials is increasing, but there is little consensus about how such studies should be conducted and reported. At a workshop in Durham, North Carolina, we sought to identify areas of agreement about how the primary findings of economic evaluations in multinational clinical trials should be generated and presented. In this paper, we propose a framework for classifying multinational economic evaluations according to (a) the sources of an analyst's estimates of resource use and clinical effectiveness and (b) the analyst's method of estimating costs. We review existing studies in the cardiology literature in the context of the proposed framework. We then describe important methodological and practical considerations in conducting multinational economic evaluations and summarize the advantages and disadvantages of each approach. Finally, we describe opportunities for future research. Delineation of the various approaches to multinational economic evaluation may assist researchers, peer reviewers, journal editors, and decision makers in evaluating the strengths and limitations of particular studies.

Cost-effectiveness analysis for multinational clinical trials.

Clinical trials of cost-effectiveness are often conducted in more than one country. The two most common ways of dealing with the multinational nature of the data are either to calculate a pooled estimate or to stratify results by country. Since the between-country heterogeneity in costs is potentially substantial, pooled estimates may be difficult to interpret for any one country. Policy decisions are often made at a national level, and so country-specific results are important. However, country-specific analyses will be based on fewer patients and will often fail to provide adequate precision for statistical analyses. Shrinkage estimation is a compromise between these two methods and has been used successfully in other fields. These estimates are country-specific yet less variable than those derived through a subgroup approach. Univariate and multivariate shrinkage estimators for costs and effects are proposed, then compared with one another and to the traditional methods in a simulation study. The methods are illustrated using data from a multinational trial evaluating the cost-effectiveness of three thrombolytic drug regimens in patients with acute myocardial infarction.

Cost-effectiveness of physiologic pacing: results of the Canadian Health Economic Assessment of Physiologic Pacing.

OBJECTIVES: The purpose of this study was to determine the cost-effectiveness of physiologic pacemakers. BACKGROUND: The Canadian Trial of Physiologic Pacing (CTOPP) was a large randomized trial that evaluated the efficacy of physiologic pacing compared with ventricular pacing. CTOPP also included a prospective cost-effectiveness substudy. METHODS: Resource usage and costs were collected from a subset of 472 patients (of 1,094) who received a physiologic pacemaker and 586 (of 1,474) who received a ventricular pacemaker. Costs included initial pacemaker implantation and all health care follow-up costs over a follow-up of 5.2 years. Costs are reported in 2004 Canadian dollars (1 Canadian dollar = 0.76 US dollars), with adjustments for censoring. Incremental cost-effectiveness was estimated as the ratio of the difference (treatment-control) in mean cost to the difference in life expectancy (mean survival), with costs and effects discounted at 3% per year. RESULTS: Over a mean follow-up of 3.1 years, physiologic pacing was associated with a gain of 0.01 life-years. This benefit increases to 0.25 life-years in the subgroup of patients with an intrinsic (unpaced) heart rate < or =60 bpm. Physiologic pacing was more expensive than ventricular (16,833 Canadian dollars vs 13,857 US dollars), largely because of the increased cost of dual-chamber devices. Among all substudy patients, the incremental cost-effectiveness of physiologic pacing is 297,600 Canadian dollars per life-year gained; however, this value falls to 16,343 Canadian dollars in patients with an intrinsic heart rate >60. CONCLUSIONS: In the short term, a strategy of routine implantation of physiologic pacemakers is not cost-effective by currently accepted standards. The selective use of these devices in patients likely to be pacemaker dependent appears to be cost-effective. Further studies with longer follow-up and which consider the benefit of reducing nonfatal cardiac events would be valuable.

Country specific cost comparisons from multinational clinical trials using empirical Bayesian shrinkage estimation: the Canadian ASSENT-3 economic analysis.

The growing number of multinational clinical trials in which patient-level health care resource data are collected have raised the issue of which is the best approach for making inference for individual countries with respect to the between-treatment difference in mean cost. We describe and discuss the relative merits of three approaches. The first uses the random effects pooled estimate from all countries to estimate the difference for any particular country. The second approach estimates the difference using only the data from the specific country in question. Using empirical Bayes estimation a third approach estimates the country-specific difference using a variance-weighted linear sum of the estimates provided by the other two approaches. The approaches are illustrated and compared using the data from the ASSENT-3 trial.

Analysis of a pharmaceutical risk sharing agreement based on the purchaser's total budget.

Many public and private healthcare payers use formularies as a tool for controlling drug costs and quality. Although the price per dose is often negotiated as part of the formulary listing, payers may still face unlimited financial risk if demand is much greater than expected at the time of listing. The requirement for drug manufacturers to submit a budget impact analysis as part of the drug approval process suggests that payers are concerned not only with the cost effectiveness of a proposed drug but also with the potential increase in total expenditures that may result from new formulary listings. In this paper we define and analyze a model for financial risk sharing based on the total budget. Our analysis focuses on optimal decision making by manufacturers in the presence of a specific risk sharing agreement. We derive a manufacturer's optimal statement of budget impact and discuss several properties of the optimal solution.

Cost-effectiveness of rhythm versus rate control in atrial fibrillation.

BACKGROUND: Atrial fibrillation is the most common type of sustained cardiac arrhythmia, but recent trials have identified no clear advantage of rhythm control over rate control. Consequently, economic factors often play a role in guiding treatment selection. OBJECTIVE: To estimate the cost-effectiveness of rhythm-control versus rate-control strategies for atrial fibrillation in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM). DESIGN: Retrospective economic evaluation. Nonparametric bootstrapping was used to estimate the distribution of incremental costs and effects on the cost-effectiveness plane. DATA SOURCES: Data on survival and use of health care resources were obtained for all 4060 AFFIRM participants. Unit costs were estimated from various U.S. databases. TARGET POPULATION: Patients with atrial fibrillation who were 65 years of age or who had other risk factors for stroke or death, similar to those enrolled in AFFIRM. TIME HORIZON: Mean follow-up of 3.5 years. PERSPECTIVE: Third-party payer. INTERVENTIONS: Management of patients with atrial fibrillation with antiarrhythmic drugs (rhythm control) compared with drugs that control heart rate (rate control). OUTCOME MEASURES: Mean survival, resource use, costs, and cost-effectiveness. RESULTS OF BASE-CASE ANALYSIS: A mean survival gain of 0.08 year (P = 0.10) was observed for rate control. Patients in the rate-control group used fewer resources (hospital days, pacemaker procedures, cardioversions, and short-stay and emergency department visits). Rate control costs 5077 dollars less per person than rhythm control. RESULTS OF SENSITIVITY ANALYSIS: Cost savings ranged from 2189 dollars o 5481 dollars per person. Rhythm control was more costly and less effective than rate control in 95% of the bootstrap replicates over a wide range of cost assumptions. LIMITATIONS: Resource use was limited to key items collected in AFFIRM, and the results are generalizable only to similar patient populations with atrial fibrillation. CONCLUSION: Rate control is a cost-effective approach to the management of atrial fibrillation compared with maintenance of sinus rhythm in patients with atrial fibrillation similar to those enrolled in AFFIRM.

Advances in risk-benefit evaluation using probabilistic simulation methods: an application to the prophylaxis of deep vein thrombosis.

OBJECTIVE: To demonstrate the use of probabilistic simulation modeling to estimate the joint density of therapeutic risks and benefits. Published data are used to introduce the risk-benefit acceptability curve as a novel method of illustrating risk-benefit analysis. STUDY DESIGN AND SETTING: Using published data, we performed a second-order Monte Carlo simulation to estimate the joint density of major bleeding and deep vein thrombosis (DVT) secondary to enoxaparin or unfractionated heparin. Within a Bayesian framework, beta-distributions for the probabilities of experiencing a DVT and major bleed were derived from the clinical trial, and incremental probabilities were calculated. RESULTS: The incremental risk-benefit pairs from 3,000 simulations are presented on a risk-benefit plane. To accommodate different risk preferences, the results are also illustrated using a risk-benefit acceptability curve, which incorporates different risk-benefit acceptability thresholds (mu), or the number of major bleeds one is willing to accept in order to avert one DVT. Finally, a net-benefit curve is used to illustrate the risk-benefit ratio and the derivation of 95% confidence intervals around the ratio. CONCLUSION: Modern simulation methods permit the estimation of the joint density of risks and benefits with their associated uncertainty, and within a Bayesian framework, facilitate the estimation of the probability that a therapy is net-beneficial over different preference thresholds for risk-benefit trade-offs.

Cost-effectiveness acceptability curves--facts, fallacies and frequently asked questions.

Cost-effectiveness acceptability curves (CEACs) have been widely adopted as a method to quantify and graphically represent uncertainty in economic evaluation studies of health-care technologies. However, there remain some common fallacies regarding the nature and shape of CEACs that largely result from the 'textbook' illustration of the CEAC. This 'textbook' CEAC shows a smooth curve starting at probability 0, with an asymptote to 1 for higher money values of the health outcome (lambda). But this familiar 'ogive' shape which makes the 'textbook' CEAC look like a cumulative distribution function is just one special case of the CEAC. The reality is that the CEAC can take many shapes and turns because it is a graphic transformation from the cost-effectiveness plane, where the joint density of incremental costs and effects may 'straddle' quadrants with attendant discontinuities and asymptotes. In fact CEACs: (i) do not have to cut the y-axis at 0; (ii) do not have to asymptote to 1; (iii) are not always monotonically increasing in lambda; and (iv) do not represent cumulative distribution functions (cdfs). Within this paper we present a 'gallery' of CEACs in order to identify the fallacies and illustrate the facts surrounding the CEAC. The aim of the paper is to serve as a reference tool to accompany the increased use of CEACs within major medical journals.

Principles of good modeling practice in healthcare cost-effectiveness studies.

Decision analytic models are increasingly being used to present information on the costs and effects of both new and existing healthcare technologies. However, despite this increase, the literature on what constitutes 'quality' or 'good practice' in modeling is sparse, confusing and often conflicting. As a result there is a need to summarize these quality assurance and good practice principles into a framework that is useful for modelers and users of models alike. This review has attempted to summarize these principles into five broad categories that will assist in assessing whether a model should be considered 'SAVED' (has structural integrity, uses appropriate input data and calculation methods, validates the model output, has extensive use and reporting of sensitivity analysis, and if there is detailed and unbiased reporting and interpretation of study findings). These principles span every aspect of the cost-effectiveness analysis from model conception, development and calculation, to presentation and interpretation of the results. Modelers are strongly encouraged to actively consider these principles throughout the entire process of model development, analysis and write up. Users of modeling studies should be familiar with these principles in order to correctly appraise studies for their applicability, validity and interpretability.

A methodological guide to performing a cost-utility study comparing surgical techniques.

BACKGROUND: When recommending the adoption of a new surgical intervention as opposed to maintaining an old one, surgeons need to consider the opportunity cost, which is the value of the forgone benefits. To inform these decisions, surgeons can use economic analyses of surgical practices. Unfortunately, economic analyses conducted alongside randomized controlled trials in surgery are rare. OBJECTIVES: The objective of the present study was to use data from a small randomized controlled trial to illustrate the methodology for a cost-utility analysis comparing two techniques of carpal tunnel release: open release without ('usual' technique) and with ('novel' technique) ligament reconstruction. METHODS: Eighteen eligible patients were entered into this prospective study. Fifteen were followed to six weeks postoperatively. One day preoperatively, and five days, three weeks and six weeks postoperatively, patients completed a self-administered Health Utilities Index Mark 2-3 questionnaire (utilities) and a case report form from which resource utilization (cost) was collected. Utilities were expressed as quality-adjusted life weeks, a fraction of quality-adjusted life years. RESULTS: The mean total cost of the usual technique was lower than the novel technique, and the mean quality-adjusted life week was higher, favouring the usual technique. Indirect costs were four to nine times higher than direct costs in both techniques. CONCLUSION: The novel technique was more costly and less effective, and fell in the 'lose-lose' quadrant of the cost-effectiveness plane; it was rejected in favour of the usual technique. This methodology should be applied when deciding whether to adopt novel surgical techniques in plastic surgery to optimize scarce health care resources.

HISTORIQUE: Au moment de recommander l'adoption d'une nou-velle intervention chirurgicale au lieu de conserver une ancienne intervention, les chirurgiens doivent tenir compte du coût de renonciation, qui correspond à la valeur des avantages auxquels ils renoncent. Pour étayer leurs décisions, les chirurgiens peuvent utiliser des analyses économiques des pratiques chirurgicales. Malheureusement, les analyses économiques menées conjointement avec des essais aléatoires et contrôlés sont rares. OBJECTIFS: La présente étude visait à utiliser les données d'un petit essai aléatoire et contrôlé pour illustrer la méthodologie d'une analyse coût-utilité comparant deux techniques de libération du tunnel du canal carpien : une libération ouverte sans (la technique « habituelle ¼) et avec (la « nouvelle ¼ technique) reconstruction ligamentaire. MÉTHODOLOGIE: Dix-huit patients admissibles ont participé à cette étude prospective. Quinze ont été suivis jusqu'à six semaines après l'opération. Un jour avant l'opération, puis cinq jours, trois semaines et six semaines après l'opération, les patients ont rempli eux-mêmes un questionnaire Health Utilities Index Mark 2-3 (utilité) et un formulaire de rapport de cas à partir duquel l'utilisation des ressources (coût) a été col-ligée. L'utilité était exprimée selon le nombre de semaines-personnes sans invalidité, une fraction des années-personnes sans invalidité. RÉSULTATS: Le coût total moyen de la technique habituelle était inférieur à celui de la nouvelle technique, et les semaines-personnes moyennes sans invalidité étaient plus élevées, ce qui favorisait la technique habituelle. Dans les deux techniques, les coûts indirects étaient de quatre à neuf fois plus élevés que les coûts directs. CONCLUSION: La nouvelle technique était plus coûteuse et moins efficace, et se classait dans le quadrant de double contrainte des régimes coût-efficacité. Elle a donc été rejetée en faveur de la technique habituelle. Cette méthodologie devrait être appliquée au moment de décider s'il est préférable d'adopter une nouvelle technique chirurgicale en chirurgie plastique, afin d'optimiser des ressources de santé limitées.

A view from the bridge: agreement between the SF-6D utility algorithm and the Health Utilities Index.

BACKGROUND: The SF-6D is a new health state classification and utility scoring system based on 6 dimensions ('6D') of the Short Form 36, and permits a "bridging" transformation between SF-36 responses and utilities. The Health Utilities Index, mark 3 (HUI3) is a valid and reliable multi-attribute health utility scale that is widely used. We assessed within-subject agreement between SF-6D utilities and those from HUI3. METHODS: Patients at increased risk of sudden cardiac death and participating in a randomized trial of implantable defibrillator therapy completed both instruments at baseline. Score distributions were inspected by scatterplot and histogram and mean score differences compared by paired t-test. Pearson correlation was computed between instrument scores and also between dimension scores within instruments. Between-instrument agreement was by intra-class correlation coefficient (ICC). RESULTS: SF-6D and HUI3 forms were available from 246 patients. Mean scores for HUI3 and SF-6D were 0.61 (95% CI 0.60-0.63) and 0.58 (95% CI 0.54-0.62) respectively; a difference of 0.03 (p<0.03). Score intervals for HUI3 and SF-6D were (-0.21 to 1.0) and (0.30-0.95). Correlation between the instrument scores was 0.58 (95% CI 0.48-0.68) and agreement by ICC was 0.42 (95% CI 0.31-0.52). Correlations between dimensions of SF-6D were higher than for HUI3. CONCLUSIONS: Our study casts doubt on the whether utilities and QALYs estimated via SF-6D are comparable with those from HUI3. Utility differences may be due to differences in underlying concepts of health being measured, or different measurement approaches, or both. No gold standard exists for utility measurement and the SF-6D is a valuable addition that permits SF-36 data to be transformed into utilities to estimate QALYs. The challenge is developing a better understanding as to why these classification-based utility instruments differ so markedly in their distributions and point estimates of derived utilities.

Review of economic evaluations of radiofrequency catheter ablation for cardiac arrhythmias.

A systematic review of current studies on the cost effectiveness of catheter ablation for treatment of tachycardia in adults was undertaken. The results are summarized based on a predefined framework of principles for economic evaluation. Of 192 abstracts identified, only three cost effectiveness studies were identified. Each focused on a different and specific patient group with selected target disorders, and used decision analysis modelling to estimate cost effectiveness. Radiofrequency catheter ablation is likely to be economically attractive compared with drug therapy in adult patients with frequently symptomatic paroxysmal supraventricular tachycardia (radiofrequency catheter ablation dominates drug therapy options) or in ventricular tachycardia patients with pre-existing ischemic coronary disease (cost effectiveness ratio of about US $21,000 per quality adjusted life year), but not in the treatment of asymptomatic Wolff-Parkinson-White syndrome patients. However, these studies evaluated different types of tachycardias in differing patient populations and all are based on United States data, so decision-makers must be cautious when applying these results to a general population with tachycardia in the Canadian context.

Measures of importance for economic analysis based on decision modeling.

In probabilistic economic analysis, the uncertainty concerning input parameters is quantified, and determines the level of uncertainty over the optimal decision. Researchers from a wide range of disciplines employ mathematical models to simulate complex processes. Common through many such disciplines is the conduct of importance analysis to determine those input parameters that contribute most to the uncertainty over the optimal decision based on the results of the analysis. In this study, we compare a range of potential importance measures to see how they compare with methods used in economic analysis. Techniques were classified as variance/correlation, information, probability, entropy, or elasticity-based measures. A selection of the most commonly used measures were applied to an economic model of treatment for patients with Parkinson's disease. Techniques were evaluated in terms of their ranking of variables, complexity, and interpretation.

Economic considerations for health insurance coverage of emerging genetic tests.

Public and private health insurance plans face the question of whether to cover emerging genetic tests for cancer and other diseases. This paper outlines issues in the economic evaluation of new genetic tests, illustrating key methodological issues and policy implications with findings from a comprehensive and systematic review of the 14 full economic evaluations published over the past 5 years that have addressed both the costs and consequences of molecular genetic tests. Key questions for framing an evaluation include: whose viewpoint matters, which costs and consequences are relevant, and to which clinical alternatives should new genetic tests be compared? While economic evaluation research can inform coverage decisions about genetic tests, the coverage decision-making process must also inform economic researchers about the aims, context, and value systems within which genetic tests will be covered and practised.