Do oncologists believe new cancer drugs offer good value?

BACKGROUND

Substantial debate centers on the high cost and relative value of new cancer therapies. Oncologists play a pivotal role in treatment decisions, yet it is unclear whether they perceive high-cost new treatments to offer good value or how therapeutic costs factor into their treatment recommendations.

METHODS

We surveyed 139 academic medical oncologists at two academic hospitals in Boston. We asked respondents to provide estimates for the cost and effectiveness of bevacizumab and whether they believed the treatment offered "good value." We also asked respondents to judge how large a gain in life expectancy would justify a hypothetical cancer drug that costs $70,000 a year. Using this information, we calculated implied cost-effectiveness thresholds. Finally, we explored respondents' views on the role of cost in treatment decisions.

RESULTS

Ninety academic oncologists (65%) completed the survey. Seventy-eight percent stated that patients should have access to "effective" care regardless of cost. Implied cost-effectiveness thresholds, derived from the bevacizumab and hypothetical scenarios, averaged roughly $300,000 per quality-adjusted-life-year (QALY). Only 25% of oncologists felt that bevacizumab offered "good value."

CONCLUSIONS

A majority of academic oncologists stated that cost does not influence their clinical practice, nor should it limit access to "effective" care. Yet respondents did not consider all effective drugs to be of good value. Implied cost-effectiveness thresholds were $300,000/QALY--a value higher than the $50,000 standard often cited. A subset of oncologists were sensitive to cost, believing it should factor into clinical decisions. These findings reflect the ongoing controversies within the medical community as expensive new therapies enter the system.

Diffusion of published cost-utility analyses in the field of health policy and practice

OBJECTIVES

The diffusion of cost-utility analyses (CUAs) through the medical literature was examined, documenting visible patterns and determining how they correspond with expectations about the diffusion of process innovations.

METHODS

This study used 539 CUAs from a registry. It includes data elements comprising year of publication, the research center in which the study was performed, the clinical area covered by the CUA, and the specific journal. Finally, each paper was assigned to a journal type that could be one of the three categories: health services research, general medicine, or clinical specialty.

RESULTS

When the average number of publications is plotted against time, the plot reveals an S-shaped curve. It appears that, whereas CUAs initially were published more frequently in general medical or health services research journals, there was a clear increase in the diffusion of CUA into subspecialty journals over time. The concentration ratio for research centers as measured by the Herfindhal-Hirschman Index decreased over time.

CONCLUSIONS

The spread of CUA through the medical literature follows patterns identified for the diffusion of other new technologies and processes. Future research should focus on what impact this spread has had on the practice of medicine and formulation of health policy.

Do drug formulary policies reflect evidence of value?

OBJECTIVE

To investigate the extent to which preferred drug lists and tiered formularies reflect evidence of value, as measured in published cost-utility analyses (CUAs).

METHODS

Using 1998-2001 data from a large registry of cost-effectiveness analyses, we examined the 2004 Florida Medicaid preferred drug list and the 2004 Harvard Pilgrim Pharmacy Program 3-tier formulary, and compared cost-utility ratios (standardized to 2002 US dollars) of drugs with preferred and nonpreferred status.

RESULTS

Few drugs on the formularies had any cost-utility data available. Of those that did, median cost-utility ratios were somewhat higher (less favorable) for Florida's preferred drugs compared with the nonpreferred drugs (25,465 dollars vs 13,085 dollars; P = .09). Ratios did not differ for drugs on tiers 1 and 2 of the Harvard Pilgrim formulary, although they were higher for tier 3 and for excluded drugs (18,309 dollars, 18,846 dollars, 52,119 dollars, and 22,580 dollars, respectively; P = .01). Among therapies reported to be cost-saving or to have cost-utility ratios below 50,000 dollars, 77% had favored status in Florida Medicaid and 73% in Harvard Pilgrim. Among dominated drug interventions (reported to be more costly and less effective than alternatives), 95% had favored status in Florida Medicaid and 56% in Harvard Pilgrim.

CONCLUSIONS

This study underscores the paucity of published cost-utility data available to formulary committees. Some discrepancies prevail between the value of drugs, as reflected in published cost-utility ratios, and the formulary placement policies of 2 large health plans.

Economic evaluation in the US: what is the missing link?

In this paper we consider the evolving American healthcare landscape and what it means for the use of economic evaluation of health interventions. We emphasise that use of economic evaluation in the US is unlikely to follow the European, Canadian or Australian models, which use cost effectiveness openly and explicitly, given the decentralised manner in which American healthcare is organised, financed and delivered, as well as different political systems and traditions, and cultural expectations and attitudes surrounding healthcare. However, this does not mean that considerations of value are absent. On the contrary, measurement of value remains near the top of the agenda among US policy makers. With a few exceptions, it just isn't playing out explicitly. In the American context, it means in part heightened debate over clinical evidence, and cost sharing. In some cases, payers are also considering economic evaluation more directly in coverage and reimbursement decisions and indirectly for clinical practice guidelines and best practice recommendations. A dramatic shift in policy towards cost effectiveness seems unlikely in the near future. Change will likely come in incremental fashion through experimentation, and perhaps in selected circumstances with public and private leaders willing to take the political risks. Conceivably, more substantial change will occur with a major shift in the political leadership in Washington, DC in the legislative or executive branches, and/or with an economic downturn and severe pressures on federal and state health budgets. However, a more likely outcome is the ongoing indirect use of cost-effectiveness information.

Emerging Lessons From The Drug Effectiveness Review Project

The Drug Effectiveness Review Project (DERP) is an alliance of fifteen states and two private organizations, which have pooled resources to synthesize and judge clinical evidence for drug-class reviews. The experience shines a bright light on challenges involved in implementing an evidence-based medicine process to inform drug formulary decisions: When should evidence reviewers accept surrogate markers and assume therapeutic class effects? How open and participatory should review procedures be? Should reviewers consider cost-effectiveness information? What is the appropriate role of the public sector in judging evidence? The DERP illustrates that attempts to undertake evidence-based reviews, apart from the methods themselves, which continue to evolve, involve questions of organization, process, and leadership.

The arrival of economic evidence in managed care formulary decisions: the unsolicited request process

Managed care plans have traditionally resisted using economic evidence explicitly in drug formulary decisions, even as they used ever more aggressive and sophisticated processes for managing care. In recent years, this has changed as health plans have begun to adopt evidence-based and value-based formulary submission guidelines. The guidelines have the potential to serve as a national unifying template for pharmacy and therapeutics committees to consider clinical and economic information in a systematic and rigorous fashion. However, many questions remain about their use and about the nature of communications (called "unsolicited requests") from plans to drug companies for information. This article describes the unsolicited request process and its potential impact on the use of economic evidence in formulary decisions.

Cost-Effectiveness of Topiramate in Migraine Prevention: Results From a Pharmacoeconomic Model of Topiramate Treatment

OBJECTIVE

Patients whose migraines are frequent, cause disruptions of daily routines, or are unresponsive to acute treatment are primary candidates for preventive migraine therapy. This cost-effectiveness model assesses the clinical and economic impact of topiramate (TPM) therapy versus no preventive treatment for migraine headache in the United States.

BACKGROUND

Despite significant progress in treatment options, the economic burden of migraine to patients, employers, health systems, and society is substantial. Treatment strategies for migraine are directed toward managing acute episodes. However, preventive therapy should be used for patients with frequent migraine attacks (>2 per month) or those experiencing attacks that disrupt daily routines.

METHODS

Data for the model were obtained from the published literature and pooled results of two randomized, double-blinded, placebo-controlled trials of TPM in migraine prevention. Model inputs included baseline migraine frequency (the base case assumed 6 per month, consistent with the average rate in the TPM trials), treatment discontinuation (including discontinuation due to adverse events), treatment response (ie, > or = 75%, 50% to 75%, and <50% reduction in migraine frequency), cost of preventive therapy (TPM plus physician visits for medication titration), cost of acute treatment per attack (including pharmacy and medical service costs), hours of disability per attack, hourly wage, and quality-of-life (utility) weights. Model outcomes included the number of migraines averted, disability hours, total cost of acute and preventive treatment, and lost wages. Results were expressed as cost per migraine averted and cost per quality-adjusted life years (QALY). All costs were stated as 2002 U.S. dollars. We also conducted sensitivity analyses to assess the robustness of model findings with respect to variation in key parameters.

RESULTS

We estimated that the use of TPM would prevent 1.85 migraines per patient and almost 5 hours of disability per month versus no preventive treatment. Resulting savings in cost of acute treatment (dollar 27) and work loss (dollar 51) offset 68% of the expected monthly cost of TPM (dollar 113). The incremental cost per migraine averted was dollar 19, while the incremental cost per QALY was estimated to be dollar 10,888 (dollar 26,191 when indirect costs were excluded from the analysis). Model results were sensitive to baseline migraine rate and gain in health utility from migraine prevention.

CONCLUSIONS

Economic savings associated with reduced migraine frequency offset approximately two thirds of the cost of preventive TPM therapy. The cost-effectiveness of TPM depends on utility gains associated with a reduced frequency of migraine headaches, which is the subject of ongoing research. However, results from our model suggest that the use of TPM in prevention of migraine may offer reasonable value for money relative to many well-accepted medical interventions.

A synthesis of cost-utility analysis literature in infectious disease

The purpose of this review is to understand infectious disease-related cost-utility analyses by describing published analyses, examining growth and quality trends over time, examining factors related to quality, and summarising standardised results. 122 cost-utility analyses and 352 cost-utility ratios were identified. Pharmaceutical interventions were most common (47.5%); three author groups accounted for 42.8% of pharmaceutical ratios. High-volume journals (three or more published cost-utility analyses) published higher quality analyses than low-volume journals (p<0.001). Use of probabilistic sensitivity analysis and discounting at 3% were more frequently found in the years after the US Public Health Service Panel on Cost-Effectiveness in Health and Medicine recommendations (p<0.01). Median ratios varied from US13,500 dollars/quality-adjusted life year (QALY) for immunisations to US810,000 dollars/QALY for blood safety. Publication of infectious disease cost-utility analyses is increasing. The results of cost-utility analyses have important implications for the development of clinical guidelines and resource allocation decisions. More trained investigators and better peer-review processes are needed.

Cost-utility analyses in orthopaedic surgery

BACKGROUND

The rising cost of health care has increased the need for the orthopaedic community to understand and apply economic evaluations. We critically reviewed the literature on orthopaedic cost-utility analysis to determine which subspecialty areas are represented, the cost-utility ratios that have been utilized, and the quality of the present literature.

METHODS

We searched the English-language medical literature published between 1976 and 2001 for orthopaedic-related cost-utility analyses in which outcomes were reported as cost per quality-adjusted life year. Two trained reviewers independently audited each article to abstract data on the methods and reporting practices used in the study as well as the cost-utility ratios derived by the analysis.

RESULTS

Our search yielded thirty-seven studies, in which 116 cost-utility ratios were presented. Eleven of the studies were investigations of treatment strategies in total joint arthroplasty. Study methods varied substantially, with only five studies (14%) including four key criteria recommended by the United States Panel on Cost-Effectiveness in Health and Medicine. According to a reader-assigned measure of study quality, cost-utility analyses in orthopaedics were of lower quality than those in other areas of medicine (p = 0.04). While the number of orthopaedic studies has increased in the last decade, the quality did not improve over time and did not differ according to subspecialty area or journal type. For the majority of the interventions that were studied, the cost-utility ratio was below the commonly used threshold of $50,000 per quality-adjusted life year for acceptable cost-effectiveness.

CONCLUSIONS

Because of limitations in methodology, the current body of literature on orthopaedic cost-utility analyses has a limited ability to guide policy, but it can be useful for setting priorities and guiding research. Future research with clear and transparent reporting is needed in all subspecialty areas of orthopaedic practice.

Economic burden of pertussis and the impact of immunization

Although routine use of vaccines has diminished the incidence of pertussis disease, it has not eliminated the pathogen. Epidemiologic data confirm that pertussis remains a significant health problem in all age groups. Disease burden is highest in infants, in whom pertussis disease frequently leads to severe complications and mortality, although it is also a significant health burden in adolescents and adults, in whom the reported incidence of pertussis is increasing. The Global Pertussis Initiative reviewed the literature to find data that express the economic impact of this health burden and to review economic evaluations of pertussis immunization. Although only limited data on the direct and indirect costs of pertussis are available, they suggest that it poses a significant economic burden and indicate that the direct medical costs of pertussis depend on the rate of hospitalization and the severity of complications, and are highest in infants. The indirect costs of pertussis also appear to be considerable, particularly among adults, in whom the disease reduces work productivity, because of either personal illness or child care responsibilities. Several health economic models on the cost effectiveness of childhood immunization strategies have been published, and although constrained by missing data, have generally found childhood immunization strategies to be cost-effective. Economic analyses of adolescent and adult immunization strategies have also been conducted, but the findings of these studies have been inconsistent. The most recent evaluations, using much higher estimates of incidence than reported previously, suggest that immunization of adolescents and specific adult subgroups may be cost-effective. The literature review confirmed that the economic burden of pertussis is substantial, but there are gaps in existing information. In the short term, further economic analyses are required, particularly of adolescent and adult immunization. More importantly, collection of primary epidemiologic and economic data should be undertaken in parallel. Despite the existing gaps in data, further research using the most current data should facilitate decisions on new vaccination strategies by describing conditions for favorable results and quantifying the margin of uncertainty.

Medicare's national coverage decisions, 1999-2003: quality of evidence and review times

In 1998 Medicare amended its procedures for making national coverage decisions for new technologies in an attempt to make the process more transparent and evidence based. We examined the quality of evidence for sixty-nine technologies reviewed by Medicare since then. Determinations by the Centers for Medicare and Medicaid Services (CMS) have generally been consistent with the strength of evidence. Good clinical evidence from rigorous studies is usually lacking for the technologies Medicare considers, although in most cases the CMS covers with conditions if there is at least fair evidence that benefits outweigh harms. Decisions referred to the external Medicare Coverage Advisory Committee (MCAC) have averaged eight months longer than non-MCAC decisions.

When Is Evidence Sufficient?

Traditional conceptualizations of evidence-based medicine rely heavily on randomized controlled trials. Although initiatives to broaden definitions of evidence have been advanced, they generally have not tied evidentiary criteria formally and quantitatively to the benefits and costs involved in a decision to adopt or reject an intervention. Decision analysis provides a framework for combining information to inform the adoption decision in this manner. Value-of-information analysis, a related methodology, helps to determine whether it is worthwhile to collect additional information as well as the type of research that would be most helpful.

Growth and quality of the cost-utility literature, 1976-2001

PURPOSE

Cost-utility analyses (CUAs) have become increasingly popular, although questions persist about their comparability and credibility. Our objectives were to: 1) describe the growth and characteristics of CUAs published in the peer-reviewed literature through 2001; 2) investigate whether CUA quality has improved over time; 3) examine whether quality varies by the experience of journals in publishing CUAs, or the source of external funding for study investigators; and 4) examine changes in practices in US-based studies following recommendations of the US Panel on Cost-Effectiveness in Health and Medicine (USPCEHM). This study updates and expands our previous work, which examined CUAs through 1997.

METHODS

We conducted a systematic search of the English-language medical literature for original CUAs published from 1976 through 2001, using Medline and other databases. Each study was audited independently by two trained readers, who recorded the methodological and reporting practices used.

RESULTS

Our review identified 533 original CUAs. Comparing articles published in 1998 to 2001 (n = 305) with those published in 1976 to 1997 (n = 228), studies improved in almost all categories, including: clearly presenting the study perspective (73% vs. 52%, P < 0.001); discounting both costs and quality-adjusted life-years (82% vs. 73%, P = 0.0115); and reporting incremental cost-utility ratios (69% vs. 46%, P < 0.001). The proportion of studies disclosing funding sources did not change (65% vs. 65%, P = 0.939). Adherence to recommended practices was greater in more experienced journals, and roughly equal in industry versus non-industry-funded analyses. The data suggest an impact in methodological practices used in US-based CUAs in accordance with recommendations of the USPCEHM.

CONCLUSIONS

Adherence to methodological and reporting practices in published CUAs is improving, although many studies still omit basic elements. Medical journals, particularly those with little experience publishing cost-effectiveness analyses, should adopt and enforce standard protocols for conducting and reporting CUAs.

Health utilities in Alzheimer's disease and implications for cost-effectiveness analysis

The National Institute for Health and Clinical Excellence (NICE) provisional decision against memantine and other medications for Alzheimer's disease (AD) has generated much discussion. In its decision, NICE expressed concern about the data source used for the utility scores in the industry submission of the memantine model. NICE therefore turned to an alternative data source. However, in doing so, it made the key assumption that moderate-to-severe AD patients living in the community were independent. Furthermore, the NICE data source also had its limitations. There are numerous limitations in inferring from available data how utilities vary between dependent and non-dependent patients with AD. Most importantly, we lack direct evidence from primary data. Nonetheless, it seems reasonable to assume that patients with severe AD, and likely those with moderate AD as well, have full-time care needs, regardless of their setting. The NICE assumption that they do not results in a difference in utilities between dependent and non-dependent AD individuals of only 0.06. This seems to be at the low end of what one would consider a reasonable estimate.

Willingness to pay for avoiding coronary restenosis and repeat revascularization: results from a contingent valuation study

BACKGROUND

Despite technological improvements, percutaneous coronary intervention (PCI) remains limited by restenosis requiring further revascularization procedures during the ensuing year. New technologies aiming to reduce restenosis are expensive and may increase net healthcare costs. Economic evaluations of such therapies have been performed, but have been hindered by the need to assess the disutility of short-term health care events and repeat coronary revascularization as well as the lack of benchmark standards for intermediate health outcomes. The contingent valuation approach may offer particular advantages when evaluating treatments that improve short-term health outcomes.

OBJECTIVE

To examine patients' willingness to pay (WTP) for treatments that may reduce the risk of restenosis and repeat revascularization after PCI.

METHODS

We used a contingent valuation approach to evaluate WTP among participants in two large clinical trials evaluating new PCI devices. The baseline scenario described a 30% probability of repeat revascularization following the initial procedure. Patients were asked to indicate, using a close-ended (referendum) question, their out of pocket WTP for an improved treatment that would reduce this risk. Three different prices (500 dollars, 1000 dollars, and 1500 dollars) and three levels of absolute risk reduction (10, 20, and 30%) were randomly varied creating nine sub-samples of patients. Patients' responses were analyzed using both parametric and non-parametric methods.

RESULTS

1642 patients completed the WTP question. The WTP medians for the 10 and 20% risk reductions were 273 dollars and 366 dollars, respectively; the median WTP for the 30% risk reduction was significantly higher at 1162 dollars (P<0.001). Higher household income (OR=1.57, P<0.001) was independently associated with a higher WTP.

CONCLUSIONS

Although short-lived, avoidance of coronary restenosis may have considerable value to patients undergoing percutaneous coronary interventions. These findings may have important implications for emerging technologies such as drug-eluting stents.

The heterogeneity of schizophrenia in disease states

PREVIOUS PRESENTATION

Some of the contents of this paper have been previously presented at the 16th Annual Meeting of the International Society for Technology Assessment in Health Care June 20, 2000 in the Hague, Netherlands and at the 21st Annual Meeting of the Society for Medical Decision Making as a poster on October 3, 1999 in Reno, NV.

BACKGROUND

Studies of schizophrenia treatment often oversimplify the array of health outcomes among patients. Our objective was to derive a set of disease states for schizophrenia using the Positive and Negative Symptom Assessment Scale (PANSS) that captured the heterogeneity of symptom responses.

METHODS

Using data from a 1-year clinical trial that collected PANSS scores and costs on schizophrenic patients (N=663), we conducted a k-means cluster analyses on PANSS scores for items in five factor domains. Results of the cluster analysis were compared with a conceptual framework of disease states developed by an expert panel. Final disease states were defined by combining our conceptual framework with the empirical results. We tested its utility by examining the influence of disease state on treatment costs and prognosis.

RESULTS

Analyses led to an eight-state framework with varying levels of positive, negative, and cognitive impairment. The extent of hostile/aggressive symptoms and mood disorders correlated with severity of disease states. Direct treatment costs for schizophrenia vary significantly across disease states (F=27.47, df=7, p<0.0001), and disease state at baseline was among the most important predictors of treatment outcomes.

CONCLUSION

The disease states we describe offer a useful paradigm for understanding the links between symptom profiles and outcomes.

Cross-national comparison of technology assessment processes

Objectives:To compare methods and results among four health technology assessment organizations in different countries.

Methods:All assessment reports published between 1999 and 2001 by VATAP (United States), NICE (United Kingdom), CCOHTA (Canada), and AETS (Spain), were reviewed. Detailed information about the organization, the technology assessed, the methods used, and the recommendations made were collected. A descriptive analysis of the variables, as well as comparisons of means and proportions, was performed.

Results:Sixty-one reports assessing seventy-six technologies were published: nine (11.8 percent) by VATAP, thirty-nine (51.3 percent) by NICE, twenty (26.3 percent) by CCOHTA, and eight (10.5 percent) by AETS. A total of 64.5 percent of the technologies assessed were related to a high prevalence disease in the corresponding country. Most of the assessments addressed treatments (73.7 percent) and were mostly drugs (56.6 percent) and devices (23.7 percent). Most organizations used reviews of effectiveness and economic evaluations (64.5 percent), systematic reviews (21.1 percent), and original economic evaluations (36.7 percent). In 38.1 percent, the technology was recommended; the rest of the cases had no formal recommendations.

Conclusions:Critical issues for future technology assessment efforts are making assessment processes more consistent, transparent, and evidence-based; formalizing the inclusion of economic and ethical considerations; and making more explicit the prioritization process for selecting technologies for assessment and reassessment.

When does quality-adjusting life-years matter in cost-effectiveness analysis?

PURPOSE

This paper investigates the impact of quality-of-life adjustment on cost-effectiveness analyses, by comparing ratios from published studies that have reported both incremental costs per (unadjusted) life-year and per quality-adjusted life-year for the same intervention.

METHODS

A systematic literature search identified 228 original cost-utility analyses published prior to 1998. Sixty-three of these analyses (173 ratio pairs) reported both cost/LY and cost/QALY ratios for the same intervention, from which we calculated medians and means, the difference between ratios (cost/LY minus cost/QALY) and between reciprocals of the ratios, and cost/LY as a percentage of the corresponding cost/QALY ratio. We also compared the ratios using rank-order correlation, and assessed the frequency with which quality-adjustment resulted in a ratio crossing the widely used cost-effectiveness thresholds of 20, 000 US dollars, 50,000 US dollars, and 100,000 US dollars/QALY or LY.

RESULTS

The mean ratios were 69,100 US dollars/LY and 103,100 US dollars/QALY, with corresponding medians of 24,600 US dollars/LY and 20,400 US dollars/QALY. The mean difference between ratios was approximately -34,300 US dollars (median difference: 1300 US dollars), with 60% of ratio pairs differing by 10,000 US dollars/year or less. Mean difference between reciprocals was 59 (QA)LYs per million dollars (median: 2.1). The Spearman rank-order correlation between ratio types was 0.86 (p<0.001). Quality-adjustment led to a ratio moving either above or below 50,000 US dollars/LY (or QALY) in 8% of ratio pairs, and across 100,000 US dollars in 6% of cases.

CONCLUSIONS

In a sizable fraction of cost-utility analyses, quality adjusting did not substantially alter the estimated cost-effectiveness of an intervention, suggesting that sensitivity analyses using ad hoc adjustments or 'off-the-shelf' utility weights may be sufficient for many analyses. The collection of preference weight data should be subjected to the same scrutiny as other data inputs to cost-effectiveness analyses, and should only be under-taken if the value of this information is likely to be greater than the cost of obtaining it.

Why don't Americans use cost-effectiveness analysis?

Cost-effectiveness analysis (CEA) offers decision makers a structured, rational approach with which to improve the return on resources expended. But decades after its widespread promotion to the medical community, policy makers in the United States remain reluctant to use the approach formally. Indeed, the resistance to economic evidence in the United States in an era of evidence-based medicine in healthcare is perhaps the most notable development of all. This paper examines the resistance to CEA in the United States and explores ways in which to advance the field.

Association between preference-based health-related quality of life and asthma severity

BACKGROUND

Preference-based measures of health-related quality of life (HRQL) focus on choice and strength of preference for health outcomes. If the value people attach to the health improvement they receive from medical treatments for asthma is known, preference-based measures can be used in cost-effectiveness analyses to aid resource allocation decisions. International guidelines have been developed to guide medical management according to asthma severity defined by lung function and symptom frequency.

OBJECTIVE

To test the hypothesis that preferences correlate with asthma severity and that the relationships vary among the preference instruments used and the components of asthma severity studied.

METHODS

Preferences for subjects' health states were measured using (1) a rating scale (RS), (2) standard gamble (SG), (3) time tradeoff (TTO), (4) Health Utilities Index 3 (HUI3), and (5) Asthma Symptom Utility Index (ASUI). We measured level of airways obstruction by forced expiratory volume in 1 second (FEV1) and symptom frequency of cough, wheeze, dyspnea, and nighttime awakening. Asthma severity was defined by either percentage of predicted FEV1 or symptom frequency.

RESULTS

One hundred adults with asthma were studied. Preference scores were lowest for the HUI3 (mean, 0.57) and highest for the SG (mean, 0.91). Spearman correlations showed that the strength of the relationship between preference scores and percentage of predicted FEV1 was weak to moderate (r = 0.14-0.36). One-way analysis of variance showed that RS, TTO, and ASUI scores were significantly associated with the percentage of predicted FEV1 (P < or = .01). Both RS and HUI3 scores were significantly associated with frequency of all symptoms (P < .05).

CONCLUSIONS

Preference-based measures of HRQL are correlated with asthma severity defined by lung function or symptoms. The RS was significantly associated with level of airways obstruction and all 4 symptoms evaluated, whereas the SG was not correlated with either marker of asthma severity.

Evidence-Based And Value-Based Formulary Guidelines

Health plans and hospitals have long used drug formularies, but the processes by which formulary committees made decisions have typically lacked transparency and scientific rigor. A growing number of organizations have begun implementing formulary guidelines issued by the Academy of Managed Care Pharmacy (AMCP). These guidelines call for health plans to request formally that drug companies present a standardized "dossier" that contains detailed information not only on the drug's effectiveness and safety but also on its economic value relative to alternative therapies. This paper describes the guidelines, reviews progress to date, and analyzes several critical issues for the future.

How often do sensitivity analyses for economic parameters change cost-utility analysis conclusions?

BACKGROUND

There is limited evidence about the extent to which sensitivity analysis has been used in the cost-effectiveness literature. Sensitivity analyses for health-related QOL (HR-QOL), cost and discount rate economic parameters are of particular interest because they measure the effects of methodological and estimation uncertainties.

AIM

To investigate the use of sensitivity analyses in the pharmaceutical cost-utility literature in order to test whether a change in economic parameters could result in a different conclusion regarding the cost effectiveness of the intervention analysed.

METHODS

Cost-utility analyses of pharmaceuticals identified in a prior comprehensive audit (70 articles) were reviewed and further audited. For each base case for which sensitivity analyses were reported (n = 122), up to two sensitivity analyses for HR-QOL (n = 133), cost (n = 99), and discount rate (n = 128) were examined. Article mentions of thresholds for acceptable cost-utility ratios were recorded (total 36). Cost-utility ratios were denominated in US dollars for the year reported in each of the original articles in order to determine whether a different conclusion would have been indicated at the time the article was published. Quality ratings from the original audit for articles where sensitivity analysis results crossed the cost-utility ratio threshold above the base-case result were compared with those that did not.

RESULTS

The most frequently mentioned cost-utility thresholds were $US20,000/QALY, $US50,000/QALY, and $US100,000/QALY. The proportions of sensitivity analyses reporting quantitative results that crossed the threshold above the base-case results (or where the sensitivity analysis result was dominated) were 31% for HR-QOL sensitivity analyses, 20% for cost-sensitivity analyses, and 15% for discount-rate sensitivity analyses. Almost half of the discount-rate sensitivity analyses did not report quantitative results. Articles that reported sensitivity analyses where results crossed the cost-utility threshold above the base-case results (n = 25) were of somewhat higher quality, and were more likely to justify their sensitivity analysis parameters, than those that did not (n = 45), but the overall quality rating was only moderate.

CONCLUSIONS

Sensitivity analyses for economic parameters are widely reported and often identify whether choosing different assumptions leads to a different conclusion regarding cost effectiveness. Changes in HR-QOL and cost parameters should be used to test alternative guideline recommendations when there is uncertainty regarding these parameters. Changes in discount rates less frequently produce results that would change the conclusion about cost effectiveness. Improving the overall quality of published studies and describing the justifications for parameter ranges would allow more meaningful conclusions to be drawn from sensitivity analyses.

Cost-effectiveness of PET in the diagnosis of Alzheimer disease

PURPOSE

To evaluate the cost-effectiveness of positron emission tomography (PET) in the diagnosis of Alzheimer disease (AD) in community-dwelling patients with mild or moderate dementia who present to specialized AD centers.

MATERIALS AND METHODS

A decision-analytic model was used to compare costs and quality-adjusted life years (QALYs) associated with strategies involving single photon emission computed tomography (SPECT), dynamic susceptibility-weighted contrast material-enhanced magnetic resonance (MR) imaging, and PET as functional imaging adjuncts to the standard clinical work-up. Sensitivity analyses were performed to examine changes in test characteristics, health-related quality-of-life survey instruments, therapeutic effectiveness, and treatment rules.

RESULTS

The use of PET to confirm the results of the standard clinical work-up cost more but yielded fewer benefits than a strategy in which dynamic susceptibility-weighted contrast-enhanced MR imaging was substituted for the typically performed structural computed tomography. This relationship remained stable in scenarios in which standard diagnostic work-up accuracy, drug treatment effectiveness, and version of the Health Utilities Index were altered. Dynamic susceptibility-weighted contrast-enhanced MR imaging cost US dollars 598800 per QALY gained (range, US dollars 74400 to US dollars 1.9 million per QALY), compared with the cost of the standard diagnostic work-up. Treating all patients with dementia was the dominant imaging strategy, except when side effects in patients with non-AD-related dementia were modeled. In all scenarios, SPECT yielded fewer benefits than other strategies at a higher cost.

CONCLUSION

PET may have high diagnostic accuracy, but adding it to the standard diagnostic regimen at AD clinics would yield limited, if any, benefits at very high costs.

Examining the value and quality of health economic analyses: implications of utilizing the QHES

OBJECTIVE

To examine the increasing use of health economic studies and practical implications of evaluating their quality utilizing the Quality of Health Economic Studies (QHES) instrument.

METHODS

We first reviewed secondary references to examine ways in which health economic analyses are used in different health care settings, the manner in which these data are appraised and evaluated, and their relevance and value in decision making. The QHES, a new instrument designed to support fast, accurate initial assessments of study quality, was then introduced and validated. A case study was performed using the QHES to score the quality of 30 cost-effectiveness studies in gastroesophageal reflux disease (GERD) published since 1985. Areas where additional research could guide efforts to identify and enhance the use of higher-quality cost-effectiveness studies were suggested.

RESULTS

Results from the published validation study of the QHES demonstrated the validity of this new instrument. The resulting QHES scores in the case study of GERD papers ranged from 43 to 91 with a mean of 63.6 (SD=14.7). Approximately 27% of the studies rated had scores less than 50, and 27% had scores above or equal to 75. All 30 studies made conclusions and recommendations and justified them based on their study results. Most studies used appropriate cost and health outcome measures. Very few studies stated the perspective of their analysis and reasons for its selection. The majority of the studies did not perform incremental analysis.

CONCLUSION

An examination of the QHES validation study and the case study in GERD suggests that there is a rationale and potential utility to use a quality scoring system for cost-effectiveness studies. The QHES may play an important role in discriminating higher-quality cost-effectiveness information to enhance decision making. The QHES can also serve as a guideline for conducting and reporting future cost-effectiveness studies, as an aid in the editorial process, and for stratification in systematic reviews. Complex decisions regarding resource allocation rarely rely solely on economic considerations but do increasingly use health economic analyses. To the extent that such analyses are used, the QHES may help ensure that higher-quality analyses receive more analytic attention and greater weight in the decision-making process.

Development and validation of a grading system for the quality of cost-effectiveness studies

PURPOSE

To provide a practical quantitative tool for appraising the quality of cost-effectiveness (CE) studies.

METHODS

A committee comprising [corrected] of health economists selected a set of criteria for the instrument from an item pool. Data collected with a conjoint analysis survey on 120 international health economists were used to estimate weights for each criterion with a random effects regression model. To validate the grading system, a survey was sent to 60 individuals with health economics expertise. Participants first rated the quality of three CE studies on a visual analogue scale, and then evaluated each study using the grading system. Spearman rho and Wilcoxon tests were used to detect convergent validity and analysis of covariance (ANCOVA) for discriminant validity. Agreement between the global rating by experts and the grading system was also examined.

RESULTS

Sixteen criteria were selected. Their coefficient estimates ranged from 1.2 to 8.9, with a sum of 93.5 on a 100-point scale. The only insignificant criterion was "use of subgroup analyses." Both convergent validity and discriminant validity of the grading system were shown by the results of the Spearman rho (correlation coefficient = 0.78, P < 0.0001), Wilcoxon test (P = 0.53), and ANCOVA (F(3,146) = 5.97, p = 0.001). The grading system had good agreement with global rating by experts.

CONCLUSIONS

The instrument appears to be simple, internally consistent, and valid for measuring the perceived quality of CE studies. Applicability for use in clinical and resource allocation decision-making deserves further study.

Development and validation of a grading system for the quality of cost-effectiveness studies

PURPOSE

To provide a practical quantitative tool for appraising the quality of cost-effectiveness (CE) studies.

METHODS

A committee comprising [corrected] of health economists selected a set of criteria for the instrument from an item pool. Data collected with a conjoint analysis survey on 120 international health economists were used to estimate weights for each criterion with a random effects regression model. To validate the grading system, a survey was sent to 60 individuals with health economics expertise. Participants first rated the quality of three CE studies on a visual analogue scale, and then evaluated each study using the grading system. Spearman rho and Wilcoxon tests were used to detect convergent validity and analysis of covariance (ANCOVA) for discriminant validity. Agreement between the global rating by experts and the grading system was also examined.

RESULTS

Sixteen criteria were selected. Their coefficient estimates ranged from 1.2 to 8.9, with a sum of 93.5 on a 100-point scale. The only insignificant criterion was "use of subgroup analyses." Both convergent validity and discriminant validity of the grading system were shown by the results of the Spearman rho (correlation coefficient = 0.78, P < 0.0001), Wilcoxon test (P = 0.53), and ANCOVA (F(3,146) = 5.97, p = 0.001). The grading system had good agreement with global rating by experts.

CONCLUSIONS

The instrument appears to be simple, internally consistent, and valid for measuring the perceived quality of CE studies. Applicability for use in clinical and resource allocation decision-making deserves further study.

Do HEDIS measures reflect cost-effective practices?

PURPOSE

Whether the Health Plan Employer Data and Information Set (HEDIS) performance measures for managed care plans encourage a cost-effective use of society's resources has not been quantified. Our study objectives were to examine the cost-effectiveness evidence for the clinical practices underlying HEDIS 2000 measures and to develop a list of practices not reflected in HEDIS that have evidence of cost effectiveness.

DATA SOURCES

Two databases of economic evaluations (Harvard School of Public Health Cost-Utility Registry and the Health Economics Evaluation Database) and two published lists of cost-effectiveness ratios in health and medicine.

STUDY SELECTION

For each of the 15 "effectiveness of care" measures in HEDIS 2000, we searched the data through 1998 for cost-effectiveness ratios of similar interventions and target populations. We also searched for important interventions with evidence of cost-effectiveness (<$20,000 per life-year [LY] or quality-adjusted life year [QALY] gained), which are not included in HEDIS. All ratios were standardized to 1998 dollars. The data were collected and analyzed during fall 2000 to summer 2001.

DATA EXTRACTION

Cost-effectiveness ratios reporting outcomes in terms of cost/LY or cost/QALY gained were included if they matched the intervention and population covered by the HEDIS measure.

DATA SYNTHESIS

Evidence was available for 11 of the 15 HEDIS measures. Cost-effectiveness ranges from cost saving to $660,000/LY gained. There are numerous non-HEDIS interventions with some evidence of cost effectiveness, particularly interventions to promote healthy behaviors.

CONCLUSIONS

HEDIS measures generally reflect cost-effective practices; however, in a number of cases, practices may not be cost effective for certain subgroups. Data quality and availability as well as study perspective remain key challenges in judging cost effectiveness. Opportunities exist to refine existing measures and to develop additional measures, which may promote a more efficient use of societal resources, although more research is needed on whether these measures would also satisfy other desirable attributes of HEDIS.

FDA actions against misleading or unsubstantiated economic and quality-of-life promotional claims: an analysis of warning letters and notices of violation

OBJECTIVES

The objective of this study was to understand the types of economic and quality-of-life promotional claims the FDA considers false or misleading.

METHODS

Publicly available FDA letters (n = 569) sent to pharmaceutical companies from 1997 through 2001 for inappropriate promotional claims were reviewed. A standard data collection form was developed, including six categories for economic violations and three for QOL violations. For QOL, only letters with explicit violations for false or misleading claims using the words "quality of life" or patient "well-being" were considered. Other information collected included type of regulatory letter and media in which violations were found.

RESULTS

Twenty-eight (4.9%) letters cited false and/or misleading economic claims. The most common economic violation was "unsupported comparative claim of effectiveness, safety, or interchangeability" (n = 14). Twenty-eight (4.9%) letters cited QOL violations, of which four contained both economic and QOL violations. The most common QOL violation was "lack of substantial evidence for QOL claims" (n = 15). None of the FDA letters used the term "patient reported outcomes." Violations were found most frequently in brochure and Web site-based promotions.

CONCLUSIONS

The body of evidence that is emerging illustrates how the FDA is regulating promotional material containing misleading or unsubstantiated economic and QOL claims. However, knowing what constitutes an appropriate claim remains challenging because there are no formal guidelines describing what constitutes a violation, nor what level of substantiating evidence is required. More guidance may be needed to ensure appropriate use of these claims in drug promotions.

Economic messages in prescription drug advertisements in medical journals

BACKGROUND

The extent to which pharmaceutical companies promote the economic advantages of their products in advertisements in medical journals, and whether such claims are supported by evidence, has not been quantified. Our objectives were to examine how often prescription drug advertisements in leading medical journals contain economic messages, and to determine the types of promotional claims made and whether supporting evidence is provided.

METHODS

All prescription drug advertisements appearing in six leading general medical and specialty journals in 3 selected months annually from 1990 to 1999 were reviewed. Using a standard data collection form, two reviewers examined each ad for economic content-including mention of the drug's price, value, cost saving, or cost-effectiveness.

RESULTS

Economic messages appeared in 237 (11.1%) of the 2144 advertisements examined. Proportion of ads with economic content has increased over time (P = 0.003). Most frequently, economic ads contained statements that drugs were "less expensive" or "cost less" than alternative treatments (50.6% of economic ads). Supporting evidence for economic claims was clearly reported in 63.7% of cases, and typically referred to published drug prices rather than more detailed economic analysis. Ads for calcium channel blocking agents and ACE inhibitors frequently contained economic messages.

CONCLUSIONS

Economic messages about prescription drugs are used in advertisements in leading medical journals and their frequency may be rising. Physicians should be aware of this phenomenon, and its potential impact on their prescribing decisions. More scrutiny of the supporting evidence underlying economic claims by the medical community and regulators may be needed.

Long-term persistence in use of statin therapy in elderly patients

CONTEXT

Knowledge of long-term persistence with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (statin) therapy is limited because previous studies have observed patients for short periods of time, in closely monitored clinical trials, or in other unrepresentative settings.

OBJECTIVE

To describe the patterns and predictors of long-term persistence with statin therapy in an elderly US population.

DESIGN, SETTING, AND PATIENTS

Retrospective cohort study including 34 501 enrollees in the New Jersey Medicaid and Pharmaceutical Assistance to the Aged and Disabled programs who were 65 years of age and older, initiated statin treatment between 1990 and 1998, and who were followed up until death, disenrollment, or December 31, 1999.

MAIN OUTCOME MEASURES

Proportion of days covered (PDC) by a statin in each quarter during the first year of therapy and every 6 months thereafter; predictors of suboptimal persistence during each interval (PDC <80%) were identified using generalized linear models for repeated measures.

RESULTS

The mean PDC was 79% in the first 3 months of treatment, 56% in the second quarter, and 42% after 120 months. Only 1 patient in 4 maintained a PDC of at least 80% after 5 years. The proportion of patients with a PDC less than 80% increased in a log-linear manner, comprising 40%, 61%, and 68% of the cohort after 3, 12, and 120 months, respectively. Independent predictors of poor long-term persistence included nonwhite race, lower income, older age, less cardiovascular morbidity at initiation of therapy, depression, dementia, and occurrence of coronary heart disease events after starting treatment. Patients who initiated therapy between 1996-1998 were 21% to 25% more likely to have a PDC of at least 80% than those who started in 1990.

CONCLUSIONS

Persistence with statin therapy in older patients declines substantially over time, with the greatest drop occurring in the first 6 months of treatment. Despite slightly better persistence among patients who began treatment in recent years, long-term use remains low. Interventions are needed early in treatment and among high-risk groups, including those who experience coronary heart disease events after initiating treatment.

Impact of referral patterns on the use of chemotherapy for lung cancer

PURPOSE

To determine the extent to which unexplained variation in the use of chemotherapy for advanced lung cancer is due to access to oncologists' services as opposed to treatment decisions made after seeing an oncologist.

METHODS

We performed a retrospective cohort study of 12,015 patients over age 65 diagnosed with metastatic lung cancer between 1991 and 1996 while living in one of 11 regions monitored by a Survival, Epidemiology, and End Results (SEER) tumor registry. Assessment by an oncologist and subsequent treatment with chemotherapy were determined by examining linked Medicare claims.

RESULTS

Of patients who did not receive chemotherapy, 36% were never assessed by a physician who provides chemotherapy. Patients living in certain areas, those diagnosed in more recent years, and those who received care in a teaching hospital were all more likely to see a cancer specialist. These factors were unrelated to subsequent treatment decisions, however. Conversely, age and comorbidity did not have a significant effect on whether a patient was seen by an oncologist, but they were associated with the likelihood of subsequently receiving chemotherapy. Black race, probably acting as a proxy for lower socioeconomic status, was associated with both a diminished likelihood of seeing a cancer specialist and subsequently receiving chemotherapy.

CONCLUSION

Nonmedical factors are important determinants of whether a lung cancer patient is seen by a physician who provides chemotherapy. After seeing such a physician, treatment decisions seem to be mostly explained by appropriate medical factors. Racial and socioeconomic disparities still exist at both steps, however. As therapeutic options expand, referring physicians must ensure that biases and barriers to care do not deprive patients of the opportunity to consider all of their treatment options.

Prevalence and impact of medical comorbidity in Alzheimer's disease

BACKGROUND

We examined the prevalence of comorbid medical illnesses in Alzheimer's disease (AD) patients at different severity levels. We also examined the effect of cumulative medical comorbidity on cognition and function.

METHODS

Analyses of data from 679 AD patients (Mini-Mental State Exam score range 0-30, mean +/- SD = 11.8 +/- 8) from 13 sites (four dementia centers assessing outpatients, four managed care organizations, two assisted living facilities, and three nursing homes) prospectively recruited using a stratification approach including dementia severity and care setting. Medical comorbidity was quantified using the Cumulative Illness Rating Scale-Geriatric.

RESULTS

Across patients, 61% had three or more comorbid medical illnesses. Adjusting for age, gender, race, and care setting, medical comorbidity increased with dementia severity (mild to moderate, p <.01; moderate to severe, p <.001). Adjusting for age, educational level, gender, race, and care setting, higher medical comorbidity was associated with greater impairment in cognition (p <.001) and in self-care (p <.001).

CONCLUSIONS

Despite the limitation of a cross-sectional design, our initial findings suggest that there is a strong association between medical comorbidity and cognitive status in AD. Optimal management of medical illnesses may offer potential to improve cognition in AD.

Measuring Alzheimer's disease progression with transition probabilities: estimates from CERAD

OBJECTIVES

To estimate annual transition probabilities (i.e., the likelihood that a patient will move from one disease stage to another in a given time period) for AD progression. Transition probabilities are estimated by disease stages (mild, moderate, severe) and settings of care (community, nursing home), accounting for differences in age, gender, and behavioral symptoms as well as the length of time a patient has been in a disease stage.

METHODS

Using data from the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), the authors employed a modified survival analysis to estimate stage-to-stage and stage-to-nursing home transition probabilities. To account for individual variability, a Cox proportional hazards model was fit to the CERAD data to estimate hazard ratios for gender, age (50 to 64, 65 to 74, and more than 75 years), and level of behavioral symptoms (low/high, according to responses to the Behavioral Rating Scale for Dementia) for each of the key stage-to-stage and stage-to-nursing home transitions.

RESULTS

The transition probabilities underscore the rapid progression of patients into more severe disease stages and into nursing homes and the differences among population subgroups. In general, male gender, age under 65, and high level of behavioral symptoms were associated with higher transition probabilities to more severe disease stages. Disease progression is roughly constant as a function of the time a patient has spent in a particular stage.

CONCLUSIONS

Transition probabilities provide a useful means of characterizing AD progression. Economic models of interventions for AD should consider the varied course of progression for different population subgroups, particularly those defined by high levels of behavioral symptoms.

Public attitudes about genetic testing for Alzheimer's disease

In a general population survey (N = 314), 79 percent of respondents stated that they would take a hypothetical genetic test to predict whether they will eventually develop Alzheimer's disease. The proportion fell to 45 percent for a "partially predictive" test (which had a one in ten chance of being incorrect). Inclination to obtain testing was similar across age groups. Respondents were willing to pay $324 for the completely predictive test. Respondents stated that if they tested positive, they would sign advance directives (84 percent), get their finances in order (74 percent), and purchase long-term care insurance (69 percent). Only a third of respondents expressed concern about confidentiality. The results suggest that people value genetic testingfor personal and financial reasons, but they also underscore the need to counsel potential recipients carefully about the accuracy and implications of test information.

Modeling for health care and other policy decisions: uses, roles, and validity

The role of models to support recommendations on the cost-effective use of medical technologies and pharmaceuticals is controversial. At the heart of the controversy is the degree to which experimental or other empirical evidence should be required prior to model use. The controversy stems in part from a misconception that the role of models is to establish truth rather than to guide clinical and policy decisions. In other domains of public policy that involve human life and health, such as environmental protection and defense strategy, models are generally accepted as decision aids, and many models have been formally incorporated into regulatory processes and governmental decision making. We formulate an analytical framework for evaluating the role of models as aids to decision making. Implications for the implementation of Section 114 of the Food and Drug Administration Modernization Act (FDAMA) are derived from this framework.

The association between caregiver burden and caregiver health-related quality of life in Alzheimer disease

The burden experienced by family caregivers of individuals with Alzheimer disease (AD) affects the caregivers' overall health-related quality of life (HRQOL). Assessing the influence on HRQOL is an integral part of determining the efficacy and economic attractiveness of interventions for AD. Generic preference-weighted instruments such as the Health Utilities Index Mark 2 (HUI2) are recommended for measuring HRQOL for cost-effectiveness studies. However, these instruments focus on physical attributes and have not been tested in an AD caregiver population. We administered the HUI2 to a population of 679 caregivers to people with AD at 13 community and institutional sites in the United States. We also administered the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), a caregiver time questionnaire, and a caregiver burden instrument. The mean global HUI2 utility score for caregivers was 0.87 and varied little by the affected person's setting of care and AD stage (range, 0.86-0.89; p > 0.2). The caregiver burden scales all varied by the affected person's setting of care, and some also varied by disease severity. The mental health component summary score of the SF-36 for caregivers varied across both disease stage and setting. Caregiver time increased for caregivers of AD-affected persons with more severe cognitive impairment. Generic preference-weighted instruments may not adequately capture differences in the burden of caregivers of those with AD. The development of condition-specific preference-weighted instruments may provide the means to better estimate HRQOL in AD caregivers.

Cost-effectiveness of inhaled corticosteroids in adults with mild-to-moderate asthma: results from the asthma policy model

BACKGROUND

Inhaled corticosteroids remain underused among United States-based clinicians in treating mild-to-moderate adult asthma.

OBJECTIVE

The purpose of this investigation was to estimate the clinical impact, health-related quality of life, cost, and cost-effectiveness of inhaled corticosteroid therapy in a population of patients aged 18 years and over with FEV(1) = 60% to 100% of predicted normal.

METHODS

We performed a cost-effectiveness analysis of quick relievers (eg, short-acting beta-agonists) on an as-needed basis plus inhaled corticosteroid therapy versus quick relievers alone. A mathematical simulation model was developed to forecast symptoms, acute exacerbations, quality-adjusted life-years (QALYs), health care costs, and cost-effectiveness, measured in both dollars per QALY gained and dollars per symptom-free day gained. All evaluation outcomes were discounted at an annual rate of 3% and measured over a 10-year planning horizon. Data on the natural history of disease, drug efficacy, patient preferences, and economic costs were obtained from a variety of observational cohorts, randomized trials, and patient surveys.

RESULTS

Over a 10-year period, use of inhaled corticosteroids increases total health costs from roughly $5,200 to $8,400 and improves QALYs from 6.8 to 7.0, implying an incremental cost of $13,500 per QALY gained. Costs per symptom-free day gained are $7.50. Both per-person acute exacerbations and hospitalizations are reduced by 33%. The cost-effectiveness findings are sensitive to the assumed efficacy and side-effects of inhaled corticosteroid therapy.

CONCLUSIONS

Inhaled corticosteroids appear to deliver good comparative value in adults with mild-to-moderate asthma. Although more research is needed to understand their impact on preferences regarding side effects and compliance, these findings might be useful for priority-setting in limited resource situations.

An off-the-shelf help list: a comprehensive catalog of preference scores from published cost-utility analyses

PURPOSE

The Panel on Cost-Effectiveness in Health and Medicine recommends an organized collection of preference measure values for health states that can be used in costutility analyses (CUAs). The authors sought to construct a catalog of preference scores from published CUAs, organize the catalog by clinical categories, and identify methods of preference score assessment.

METHOD

The authors systematically searched Medline and other databases to identify original CUAs published through 1997. Information was abstracted on the health state descriptions, corresponding preference scores, method of preference score elicitation, and the source of the estimate.

RESULTS

Two hundred twenty-eight CUAs were appraised. The authors found 949 health states and corresponding preference scores. Most frequently, health states pertained to the circulatory system (21.7%), health states were valued by experts (35.8%), and values were derived through community-based preference scores (23.5%).

CONCLUSION

A catalog of preference scores for health states can be constructed. The catalog (http://www.hsph.harvard.edu/organizations/hcra/cuadatabase/ intro.html) may provide a useful reference tool for producers and consumers of CUAs but also underscores the methodologic variation and inconsistencies present in the field.

Bayesian value-of-information analysis. An application to a policy model of Alzheimer's disease

A framework is presented that distinguishes the conceptually separate decisions of which treatment strategy is optimal from the question of whether more information is required to inform this choice in the future. The authors argue that the choice of treatment strategy should be based on expected utility, and the only valid reason to characterize the uncertainty surrounding outcomes of interest is to establish the value of acquiring additional information. A Bayesian decision theoretic approach is demonstrated through a probabilistic analysis of a published policy model of Alzheimer's disease. The expected value of perfect information is estimated for the decision to adopt a new pharmaceutical for the population of patients with Alzheimer's disease in the United States. This provides an upper bound on the value of additional research. The value of information is also estimated for each of the model inputs. This analysis can focus future research by identifying those parameters where more precise estimates would be most valuable and indicating whether an experimental design would be required. We also discuss how this type of analysis can also be used to design experimental research efficiently (identifying optimal sample size and optimal sample allocation) based on the marginal cost and marginal benefit of sample information. Value-of-information analysis can provide a measure of the expected payoff from proposed research, which can be used to set priorities in research and development. It can also inform an efficient regulatory framework for new healthcare technologies: an analysis of the value of information would define when a claim for a new technology should be deemed substantiated and when evidence should be considered competent and reliable when it is not cost-effective to gather any more information.

The case for daily dialysis: its impact on costs and quality of life

Research suggests daily hemodialysis may improve clinical outcomes. To date, a comprehensive review of its implications on quality of life has not been performed, and little is known about its economic impact. We conducted an economic evaluation comparing short daily or nocturnal hemodialysis with thrice-weekly conventional in-center dialysis. Data on the quality of life and clinical effects of daily dialysis were obtained from more than 60 reports from 13 daily dialysis programs around the world (n = 197). Cost data were derived principally from the US Renal Data System, Centers for Disease Control, and Medicare Payment Advisory Commission. Resource use during daily hemodialysis was modeled after two ongoing programs in the United States. Results suggest that patients feel better and direct treatment costs could be reduced with daily dialysis. Costs are sensitive to assumptions about the effect of daily dialysis on hospital days. Reductions of at least 8% in hospital days are required for these modalities to be cost saving compared with documented reductions of 30% to 100%. Larger well-controlled studies of daily versus conventional dialysis would be helpful to determine whether daily dialysis fulfills these promises. Medicare policy, which limits payment for most patients to three dialysis treatments weekly, poses a disincentive to more widespread adoption among dialysis centers. Given this constraint to broader acceptance, we address several policy options to gain a better understanding of the potential risks and benefits of daily dialysis.

Preference-based measures in economic evaluation in health care

Estimating preferences for states of health has been an active area of research in recent years. Unlike psychophysical approaches, which discriminate levels of health status, preference-based approaches incorporate values or utilities for health outcomes and can be used in cost-effectiveness analyses to aid resource allocation decisions. This chapter considers issues and controversies involved in using preference-based measures in economic evaluation in health care, with a particular emphasis on cost-utility analysis and the estimation of quality-adjusted life years. Topics considered include techniques for measuring preferences, the use of preference-based classification systems, the relationship between patient and community preferences, methods for obtaining utilities from clinical trials, mapping health status from health utilities, the development of "off-the-shelf" preference weights, and proposed alternatives to quality-adjusted life years. We also consider applications of cost-utility analyses to public health interventions. Although cost-utility analyses have become more popular recently, many challenges remain for the field. Widespread acceptance of the methodology likely awaits more consensus on measurement techniques, as well as educational efforts in the public health and medical communities on the usefulness of the approach.

Effectiveness of chemotherapy for advanced lung cancer in the elderly: instrumental variable and propensity analysis

PURPOSE

To compare the effectiveness of chemotherapy given to elderly patients in routine practice for stage IV non-small-cell lung cancer (NSCLC) with the efficacy observed in randomized trials.

PATIENTS AND METHODS

We used instrumental variable analysis (IVA) and propensity scores (PS) to simulate the conditions of a randomized trial in a retrospective cohort of patients over age 65 from the Survival, Epidemiology, and End Results (SEER) tumor registry. Geographic variation in chemotherapy use served as the instrument for the IVA analysis, and propensity scores were calculated with a logistic model based on patient disease and sociodemographic characteristics.

RESULTS

Among 6,232 elderly patients, the instrumental variable estimate indicated an increase in median survival of 33 days and an improvement in 1-year survival of 9% attributable to chemotherapy. In a Cox regression model, chemotherapy administration was associated with a hazard ratio of 0.81 (95% confidence interval, 0.76 to 0.85). When survival was analyzed separately within propensity score quintiles, the hazard ratios were all similar, ranging from 0.78 to 0.85. These results are comparable with those of a large meta-analysis, which found a hazard ratio of 0.87 in the subgroup of patients over age 65.

CONCLUSION

Chemotherapy for stage IV NSCLC seems to have effectiveness for elderly patients and those with comorbid conditions that is similar to the efficacy seen in randomized trials containing mostly younger, highly selected patients. All suitable patients should be given the opportunity to consider palliative chemotherapy for metastatic NSCLC.

FEV(1) is associated with risk of asthma attacks in a pediatric population

BACKGROUND

FEV(1) is endorsed by the National Asthma Education and Prevention Program as a means for grading asthma severity. However, few data exist on the relationship between FEV(1) and asthma outcomes during long-term follow-up.

OBJECTIVE

We explored the relationship between the percent predicted FEV(1) (FEV(1)%) and subsequent asthma attacks in a longitudinal study of pediatric lung health.

METHODS

A retrospective cohort of 13,842 children (100,292 observations) seen annually over a 15-year interval was analyzed for measurement of pulmonary function, and a respiratory questionnaire was completed. Up to grade 9, a standard questionnaire was completed by a parent or guardian; thereafter it was completed by the patient. For each observation, the report of an attack during the past year was paired with FEV(1) recorded at the field survey 1 year earlier.

RESULTS

A progressive decrease in the proportion of individuals reporting an attack was associated with increasing decile of FEV(1)%. Two categorization schemes for FEV(1)% were examined: a scheme based on the National Asthma Education and Prevention Program recommendations (<60%, 60%-80%, and >80%), and an alternative scheme (<80%, 80%-100%, and >100%). In multivariate models, FEV(1)% was an independent predictor of attacks: among the parental report group, the odds ratios were 2.1 (95% CI, 1.3-3.4) and 1.4 (95% CI, 1.2-1.6) for FEV(1)% < 60% and FEV(1)% of 60% to 80% compared with FEV(1)% > 80%, respectively; and among the self-report group, odds ratios were 5.3 (95% CI, 2.2-12.9) and 1.4 (95% CI, 1.2-1.7) for FEV(1)% < 60% and FEV(1)% of 60% to 80% compared with FEV(1)% > 80%, respectively. With the alternative classification scheme, the relationship was similar, but the difference in risk between categories of FEV(1)% decreased.

CONCLUSION

The strong association between FEV(1)% and risk of asthma attack over the subsequent year supports an emphasis on objective measures of lung function in assessment of risk for adverse asthma outcomes.

The use of proxy respondents in studies of older adults: lessons, challenges, and opportunities

OBJECTIVE

Proxies play a critical role as sources of health information for older persons with cognitive impairment and other chronic debilitating conditions. This paper reviews the validity of proxy responses for people older than age 60 in the following areas: functioning, physical and mental health, cognition, medical care utilization, and preferences for types of care and health states.

DESIGN

A Medline review identified 24 clinical studies from 1990 to 1999 that use proxy data as a source of information about older adults.

RESULTS

In general, studies report fairly good agreement between subjects and proxies in assessments of functioning, physical health, and cognitive status, and fair-to-poor agreement in assessments of psychological well-being. Proxies tend to describe more impairment in functioning and emotional well-being, relative to subjects, a pattern that is particularly marked among persons with cognitive impairment. In addition, proxies who report more caregiver responsibilities and subjective stress from caregiver duties provide more negative assessments of subjects' health and well-being.

CONCLUSIONS

Findings tend to support the use of proxy ratings among older adults in many areas but not all when self-reports are not feasible. There is a need for more evaluation of proxy data in relation to other measures, such as performance assessments, medical records, and claims data, which may be less subject to respondent biases.

A comparison of HUI2 and HUI3 utility scores in Alzheimer's disease

PURPOSE

The Health Utilities Index (HUI) is a generic, multiattribute, preference-based health-status classification system. The HUI Mark 3 (HUI3) differs from the earlier HUI2 by modifying attributes and allowing more flexibility for capturing high levels of impairment. The authors compared HUI2 and HUI3 scores of patients with Alzheimer's disease (AD) and caregivers, and contrasted results of a cost-effectiveness analysis of new drugs for AD using the two systems.

METHODS

In a cross-sectional study of 679 AD patient/caregiver pairs, stratified by patient's disease stage (questionable/mild/moderate/severe/profound/terminal) and setting (community/assisted living/nursing home), caregivers completed the combined HUI2/HUI3 questionnaire as proxy respondents for patients and for themselves.

RESULTS

Mean (SD) global utility scores for patients were lower on the HUI3 (0.22[0.26]) than on the HUI2 (0.53 [0.21]). Patient HUI3 utility scores ranged from 0.47(0.24) for questionable AD to -0.23 (0.08) for terminal AD, compared with a range of 0.73 (0.15) to 0.14 (0.07) for the HUI2. Among the 203 patients in the severe, profound, and terminal stages, 96 (48%) had negative global HUI3 utility scores, while none had a negative HUI2 score. The utility scores for caregivers were similar on the HUI3 (0.87 [0.14]) and HUI2 (0.87 [0.11]). Cost-effectiveness analysis of a new medication to treat AD showed somewhat more favorable results using the HUI3.

CONCLUSIONS

The HUI2 and HUI3 discriminate well across AD stages. Compared with the HUI2, the HUI3 yields lower global utility scores for patients with AD, and more scores for states judged worse than dead. The HUI3 may yield substantially different results from the HUI2, particularly for persons who have serious cognitive impairments such as AD.

A comprehensive league table of cost-utility ratios and a sub-table of "panel-worthy" studies

OBJECTIVES

The authors compiled a comprehensive league table of cost/QALY ratios, and a standardized table of analyses satisfying selected Reference Case criteria from the USPHS Panel on Cost-Effectiveness in Health and Medicine.

METHODS

They identified 228 cost-utility analyses (CUAs) through literature searches, and abstracted data on methods and cost-utility ratios. The subset of "Panel-worthy" analyses used: a societal or broad health-care perspective, community or patient preference weights, net costs, incremental comparisons, and discounting of costs and QALYs.

RESULTS

The 228 CUAs included ratios for 647 interventions, ranging from cost-saving to $52,000,000/QALY (median = $12,000/QALY). The standardized table presents 112 ratios that met the "Panel-worthy" criteria, with articles published in recent years more likely to meet all of the criteria.

CONCLUSIONS

The comprehensive league table (available on the Web) provides a useful reference, but ratios may not be comparable because of methodologic variations. The standardized table focuses on studies meeting basic methodologic criteria, potentially allowing for better comparison with future Reference Case analyses. Future studies should investigate the quality of analyses' underlying assumptions in addition to whether certain key procedural protocols were met.