Assessing generalisability in model-based economic evaluation studies: a structured review in osteoporosis

Systematic Review of Tools and Approaches for Evaluating the Transferability of Health Technology Assessments Across Different Jurisdictions

BACKGROUND

This study aims to review tools that have been developed for the transferability of health technology assessment (HTA) information to different countries. HTA is increasingly being used as a tool in health policy decision-making, but its complexity and lack of local expertise have limited its usage in many countries. The World Health Organization (WHO) has taken measures to encourage countries to conduct and use HTA, including through resolutions from the Eastern Mediterranean (EM) Regional Committee in 2019. However, due to limitations in national technical capacities, there is a need to adapt HTA information from other settings to fit the specific context of each country. Therefore, this study aims to systematically review the tools that have been developed for HTA transferability and assess their strengths and limitations.

METHODS

The systematic review included studies that introduced tools, methods, and frameworks for transferability of HTA information across jurisdictions. Databases such as MEDLINE, EMBASE, Cochrane Library, Epistemonikos, Web of Science, health economic database, Scopus, and Google Scholar were searched, along with relevant bibliographies. The data was extracted and synthesized using both tabulation and narrative approaches. The evaluation of the tools involved assessing various criteria, such as user-friendliness, efficiency in screening, and considerations regarding transferability factors.

RESULTS

A total of 10 375 documents were evaluated, resulting in 17 studies that met the inclusion criteria. These 17 studies consisted of 13 newly developed tools/methods that were appraised. The majority of the models were checklists, with only a few deemed suitable for full HTA. Three models have been validated through published studies, but there is no evidence of utilization in the countries of the EM region.

CONCLUSION

While the existing tools provide valuable resources for evaluating transferability, there remains a need for a more comprehensive tool to support decision-makers in low-resource settings considering country context and capacity.

Considerations for transferability of health technology assessments: a scoping review of tools, methods, and practices

Health technology assessment (HTA) is commonly used to guide evidence-informed decisions to optimize resource use, prioritize policies, and support countries to achieve universal health coverage. Producing HTAs requires time, scientific expertise, and political commitment, but these are not available in all settings - especially in low- and middle-income countries (LMIC) where HTA processes may be less institutionalized. Transferring and adapting existing HTAs to local settings may offer a solution while reducing duplication efforts. This scoping review aims to provide an overview of tools, methods, approaches, and considerations which can aid HTA transfers. We systematically searched (from 2005 to 2020) six databases and, using predefined inclusion criteria, included twenty-two studies. Data extraction followed a structured process, while synthesis was more iterative. We identified a common approach for HTA transfers. It follows the de novo process of undertaking original HTAs, but with additional steps to assess relevance (applicability), quality, and transferability, as well as steps to adapt parameters where necessary. The EUnetHTA Adaptation Toolkit was the only tool that provided guidance for adapting multiple HTA domains. Other tools were specific to systematic reviews (n = 1) or economic evaluations (n = 12), where one provided guidance for systematic reviews of economic evaluations. Eight papers reported transferring an HTA, with only one transferring to an LMIC. Finally, we reported issues that may facilitate or hinder transferability. In conclusion, we identified fourteen transfer approaches in the form of guidance or checklists, but harmonized and pragmatic guidance for HTA transfers to suit settings with limited HTA capacity seems warranted.

Indirectness (transferability) is critical when considering existing economic evaluations for GRADE Clinical Practice Guidelines: A systematic review

OBJECTIVE

GRADE practice guideline developers often perform systematic reviews of potential economic evaluations to inform recommendation decision-making. We aimed to identify indirectness characteristics of economic evaluations, related to GRADE evidence-to-decision (EtD) theoretical frameworks, that influence selection of these articles.

STUDY DESIGN AND SETTING

MEDLINE, EMBASE, CINAHL and EconLit were systematically searched to May 2020 to identify indirectness characteristics relevant for economic evaluation transferability to GRADE evidence-to-decision (EtD) theoretical frameworks. Four reviewers screened citations to identify articles of any type that explored study characteristics most important or relevant to economic evaluation transferability, restricted to English language We generated frequencies of article features, used thematic analysis to summarize study characteristics and assessed certainty in the evidence using GRADE-CERQual.

RESULTS

We included 57 articles, with a dearth of empirical literature - some may have been missed. We identified 8 general themes and 28 sub-themes most important to transferability from 41% of articles. Moderate-to-high confidence evidence suggested that GRADE EtD domains of population, intervention and comparison research question elements, resource use estimation and methodology, and provider and decision-maker acceptability are most important indirectness study characteristics that economists consider when choosing economic evaluation outcomes for use in recommendation decision-making.

CONCLUSION

We have identified factors important for guideline developers to consider when selecting economic evaluations as research evidence. An economic competency on the development team facilitates these endeavors. This supports the GRADE Working Group's tenant of transparent reporting or availability of sufficient information elsewhere to assess indirectness.

Co-Formulations as the First Injectable in Type 2 Diabetes: A Review of Efficacy, Safety, and Implications in Clinical Practice

<b><i>Background:</i></b> Progression of type 2 diabetes will necessitate the use of injectable therapies in a significant number of people. Co-formulations of degludec with liraglutide (IDeg­Lira) and glargine with lixisenatide (IGlarLixi) are currently recommended for intensification in people with type 2 diabetes on basal insulin or glucagon-like peptide receptor agonist (GLP-1RA) alone or in people with type 2 diabetes who are naïve to insulin with very high glycated haemoglobin. Co-formulation of aspart with degludec (IDegAsp) is recommended as a substitute for premixed insulin. The aim of this article is to review the evidence in the use of co-formulations as the first injectable in type 2 diabetes and its clinical implications. <b><i>Summary:</i></b> In people with type 2 diabetes who are naïve to insulin or GLP-1RA, IDegLira and IGlarLixi achieved stable and durable glycaemic control over a wide range of baseline glycated haemoglobin (HbA1c) levels. People on IDegLira and IGlarLixi had lesser risk of hypoglycaemia and weight gain in studies compared to basal insulin and lesser gastrointestinal adverse effects in comparison to GLP-1RA. IDegAsp achieved similar glycaemic control to basal and premixed insulin with lesser risk of nocturnal hypoglycaemia. <b><i>Key Messages:</i></b> IDegLira, IGlarLixi, and IDegAsp can be used as the first injectable in people with type 2 diabetes with very high glycated haemoglobin on oral antidiabetic drugs. These co-formulations combine efficacy and durability with lesser injection burden. The components of these agents have proven cardiovascular and renal safety. Their limitations in flexibility of dosing, renal and cardiovascular considerations, and adverse effects are discussed.

Evaluating the cost-effectiveness of biologic treatments for psoriatic arthritis: can we make better use of patient data registries?

The primary aim of this study is to explore the extent to which registry data may fulfill the evidence requirements of cost-effectiveness analysis (CEA) studies evaluating biologic therapies for the treatment of psoriatic arthritis (PsA), where trial data are lacking or insufficient. In addition, the paper aims to identify how future data collection in PsA registries might be better tailored to inform CEA research. A review of the literature was performed to identify existing registries containing PsA patients. Where possible, information was extracted on the design and characteristics of the registries. The registries were then appraised according to a set of criteria that was formulated based on the methods currently used to model PsA in the CEA literature. A review of the literature identified 21 potentially relevant registries from around the world containing patients with PsA. There was substantial variation regarding the extent to which the registries, as a whole, were useful for the purposes of CEA studies. There were also notable disparities found in terms of the accessibility of the registries to researchers. The critical review conducted in this study showed that all of the registries identified are potentially useful, at least in some degree, for the purposes of informing CEA studies in PsA. However, no individual registry on its own was found to meet all of the evidence requirements when considering how the disease has been modeled previously.

Model-based economic evaluations in smoking cessation and their transferability to new contexts: a systematic review

AIMS

To identify different types of models used in economic evaluations of smoking cessation, analyse the quality of the included models examining their attributes and ascertain their transferability to a new context.

METHODS

A systematic review of the literature on the economic evaluation of smoking cessation interventions published between 1996 and April 2015, identified via Medline, EMBASE, National Health Service (NHS) Economic Evaluation Database (NHS EED), Health Technology Assessment (HTA). The checklist-based quality of the included studies and transferability scores was based on the European Network of Health Economic Evaluation Databases (EURONHEED) criteria. Studies that were not in smoking cessation, not original research, not a model-based economic evaluation, that did not consider adult population and not from a high-income country were excluded.

FINDINGS

Among the 64 economic evaluations included in the review, the state-transition Markov model was the most frequently used method (n = 30/64), with quality adjusted life years (QALY) being the most frequently used outcome measure in a life-time horizon. A small number of the included studies (13 of 64) were eligible for EURONHEED transferability checklist. The overall transferability scores ranged from 0.50 to 0.97, with an average score of 0.75. The average score per section was 0.69 (range = 0.35-0.92). The relative transferability of the studies could not be established due to a limitation present in the EURONHEED method.

CONCLUSION

All existing economic evaluations in smoking cessation lack in one or more key study attributes necessary to be fully transferable to a new context.

Acupuncture for chronic pain and depression in primary care: a programme of research

Background

There has been an increase in the utilisation of acupuncture in recent years, yet the evidence base is insufficiently well established to be certain about its clinical effectiveness and cost-effectiveness. Addressing the questions related to the evidence base will reduce uncertainty and help policy- and decision-makers with regard to whether or not wider access is appropriate and provides value for money.

Aim

Our aim was to establish the most reliable evidence on the clinical effectiveness and cost-effectiveness of acupuncture for chronic pain by drawing on relevant evidence, including recent high-quality trials, and to develop fresh evidence on acupuncture for depression. To extend the evidence base we synthesised the results of published trials using robust systematic review methodology and conducted a randomised controlled trial (RCT) of acupuncture for depression.

Methods and results

We synthesised the evidence from high-quality trials of acupuncture for chronic pain, consisting of musculoskeletal pain related to the neck and low back, osteoarthritis of the knee, and headache and migraine, involving nearly 18,000 patients. In an individual patient data (IPD) pairwise meta-analysis, acupuncture was significantly better than both sham acupuncture (p < 0.001) and usual care (p < 0.001) for all conditions. Using network meta-analyses, we compared acupuncture with other physical therapies for osteoarthritis of the knee. In both an analysis of all available evidence and an analysis of a subset of better-quality trials, using aggregate-level data, we found acupuncture to be one of the more effective therapies. We developed new Bayesian methods for analysing multiple individual patient-level data sets to evaluate heterogeneous continuous outcomes. An accompanying cost-effectiveness analysis found transcutaneous electrical nerve stimulation (TENS) to be cost-effective for osteoarthritis at a threshold of £20,000 per quality-adjusted life-year when all trials were synthesised. When the analysis was restricted to trials of higher quality with adequate allocation concealment, acupuncture was cost-effective. In a RCT of acupuncture or counselling compared with usual care for depression, in which half the patients were also experiencing comorbid pain, we found acupuncture and counselling to be clinically effective and acupuncture to be cost-effective. For patients in whom acupuncture is inappropriate or unavailable, counselling is cost-effective.

Conclusion

We have provided the most robust evidence from high-quality trials on acupuncture for chronic pain. The synthesis of high-quality IPD found that acupuncture was more effective than both usual care and sham acupuncture. Acupuncture is one of the more clinically effective physical therapies for osteoarthritis and is also cost-effective if only high-quality trials are analysed. When all trials are analysed, TENS is cost-effective. Promising clinical and economic evidence on acupuncture for depression needs to be extended to other contexts and settings. For the conditions we have investigated, the drawing together of evidence on acupuncture from this programme of research has substantially reduced levels of uncertainty. We have identified directions for further research. Our research also provides a valuable basis for considering the potential role of acupuncture as a referral option in health care and enabling providers and policy-makers to make decisions based on robust sources of evidence.

Trial registration

Current Controlled Trials ISRCTN63787732.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Investigating the Generalizability of Economic Evaluations Conducted in Italy: A Critical Review

OBJECTIVES

To assess the methodological quality of Italian health economic evaluations and their generalizability or transferability to different settings.

METHODS

A literature search was performed on the PubMed search engine to identify trial-based, nonexperimental prospective studies or model-based full economic evaluations carried out in Italy from 1995 to 2013. The studies were randomly assigned to four reviewers who applied a detailed checklist to assess the generalizability and quality of reporting. The review process followed a three-step blinded procedure. The reviewers who carried out the data extraction were blind as to the name of the author(s) of each study. Second, after the first review, articles were reassigned through a second blind randomization to a second reviewer. Finally, any disagreement between the first two reviewers was solved by a senior researcher.

RESULTS

One hundred fifty-one economic evaluations eventually met the inclusion criteria. Over time, we observed an increasing transparency in methods and a greater generalizability of results, along with a wider and more representative sample in trials and a larger adoption of transition-Markov models. However, often context-specific economic evaluations are carried out and not enough effort is made to ensure the transferability of their results to other contexts. In recent studies, cost-effectiveness analyses and the use of incremental cost-effectiveness ratio were preferred.

CONCLUSIONS

Despite a quite positive temporal trend, generalizability of results still appears as an unsolved question, even if some indication of improvement within Italian studies has been observed.

Refitting of the UKPDS 68 risk equations to contemporary routine clinical practice data in the UK

OBJECTIVE

Economic evaluations of new diabetes therapies rely heavily upon the UK Prospective Diabetes Study (UKPDS) equations for prediction of cardiovascular events; however, concerns persist regarding their relevance to current clinical practice and appropriate use in populations other than newly diagnosed patients. This study refits the UKPDS 68 event equations, using contemporary data describing low- and intermediate-risk patients.

RESEARCH DESIGN AND METHODS

Anonymized patient data describing demographics, risk factors and incidence of cardiovascular and microvascular events were extracted from The Health Improvement Network (THIN) database over the 10-year period from 1 January 2000 to 31 December 2009. Following multiple imputation of missing values, accelerated failure-time Weibull regression equations were refitted to produce new coefficients for each risk group. Discriminatory performance was assessed and compared with both UKPDS 68 and UKPDS 82 risk equations, and the implication of coefficient choice within an economic evaluation was assessed using the Cardiff type 2 diabetes model.

RESULTS

When applied to patient-level data, the three sets of coefficients (UKPDS, THIN low-risk and intermediate-risk) lead to fairly consistent predictions of the 5-year risk of events. Exceptions include lower predicted rates of myocardial infarction and higher rates of ischaemic heart disease, congestive heart failure and end-stage renal disease with both sets of revised THIN coefficients compared with UKPDS. Over a modelled lifetime, the coefficients derived from the low-risk data predict fewer total cardiovascular events compared with UKPDS, while those from the intermediate-risk data predict a greater number. The areas under the receiver-operating characteristic curves demonstrated a marginal improvement in the discriminatory performance of the refitted equations. The incremental cost-effectiveness ratio associated with dapagliflozin versus sulphonylurea in addition to metformin changed from £7,708 to £7,519 and £6,906 per QALY gained, using the THIN intermediate- and low-risk coefficients, respectively.

CONCLUSION

The results suggest that while the UKPDS equations perform best in newly diagnosed patients, they may overpredict the lifetime risk in this group and underpredict it in patients with more advanced diabetes. Implementation of the revised coefficients will result in different absolute numbers of predicted diabetes-related events; however, they are not expected to significantly affect the conclusions of economic modelling.

Potential transferability of economic evaluations of programs encouraging physical activity in children and adolescents across different countries--a systematic review of the literature

Physical inactivity is an increasing problem. Owing to limited financial resources, one method of getting information on the cost-effectiveness of different types of prevention programs is to examine existing programs and their results. The aim of this paper is to give an overview of the transferability of cost-effectiveness results of physical activity programs for children and adolescents to other contexts. Based on a systematic review of the literature, the transferability of the studies found was assessed using a sub-checklist of the European Network of Health Economic Evaluation Databases (EURONHEED). Thirteen studies of different physical activity interventions were found and analyzed. The results for transferability ranged from “low” to “very high”. A number of different factors influence a program’s cost-effectiveness (i.e., discount rate, time horizon, etc.). Therefore, transparency with regard to these factors is one fundamental element in the transferability of the results. A major point of criticism is that transferability is often limited because of lack of transparency. This paper is the first to provide both an overview and an assessment of transferability of economic evaluations of existing programs encouraging physical activity in children and adolescents. This allows decision makers to gain an impression on whether the findings are transferable to their decision contexts, which may lead to time and cost savings.

Deriving input parameters for cost-effectiveness modeling: taxonomy of data types and approaches to their statistical synthesis

BACKGROUND

The evidence base informing economic evaluation models is rarely derived from a single source. Researchers are typically expected to identify and combine available data to inform the estimation of model parameters for a particular decision problem. The absence of clear guidelines on what data can be used and how to effectively synthesize this evidence base under different scenarios inevitably leads to different approaches being used by different modelers.

OBJECTIVES

The aim of this article is to produce a taxonomy that can help modelers identify the most appropriate methods to use when synthesizing the available data for a given model parameter.

METHODS

This article developed a taxonomy based on possible scenarios faced by the analyst when dealing with the available evidence. While mainly focusing on clinical effectiveness parameters, this article also discusses strategies relevant to other key input parameters in any economic model (i.e., disease natural history, resource use/costs, and preferences).

RESULTS

The taxonomy categorizes the evidence base for health economic modeling according to whether 1) single or multiple data sources are available, 2) individual or aggregate data are available (or both), or 3) individual or multiple decision model parameters are to be estimated from the data. References to examples of the key methodological developments for each entry in the taxonomy together with citations to where such methods have been used in practice are provided throughout.

CONCLUSIONS

The use of the taxonomy developed in this article hopes to improve the quality of the synthesis of evidence informing decision models by bringing to the attention of health economics modelers recent methodological developments in this field.

TRANSFERABILITY OF HEALTH TECHNOLOGY ASSESSMENT REPORTS IN LATIN AMERICA: AN EXPLORATORY SURVEY OF RESEARCHERS AND DECISION MAKERS

Introduction: HTA agencies, especially in developing countries, are under resourced and unable to conduct the desired amount of assessments. Adapting HTA reports (HTAs) from other jurisdictions is an alternative for saving resources.

Objectives: To explore HTA transferability experiences in Latin-America and Caribbean (LAC): are decision makers (DMs) using HTAs from other jurisdictions? Are researchers adapting HTAs when developing local reports? How useful is the information found in HTAs from other jurisdictions?

Methods: Web-based survey sent to 13031 HTA researchers and DMs.

Results: We received 671 responses from 19 countries. DMs reported using HTAs from other jurisdictions to guide decisions in the majority of the situations: 52.6 percent HTAs from outside LAC (e.g., Europe), 23.1 percent from other LAC countries, and only 24.3 percent HTAs from their own countries. 63 percent of researchers reported using HTAs from other jurisdictions. Usefulness scored significantly higher for HTAs from other jurisdictions as compared to local HTAs (7.1 versus 6.0 in a 1–10 scale; p < .01). Both DMs and researchers considered the information regarding safety and effectiveness more applicable than the information on social aspects, or economic evaluation. Barriers that limit transferability had significantly different scores for HTAs from other LAC countries as compared to those from regions outside LAC (i.e., poor methodological quality 6.7 versus 5.3, different epidemiological context 6.0 versus 7.4; all p < .01).

Conclusions: HTAs from outside the region are commonly used. However, DMs and researchers agreed that HTAs from LAC had the greatest potential for transferability, provided that barriers such as poor methodological quality could be overcome.

Apparent Young's modulus of vertebral cortico-cancellous bone specimens

Up to now, due to cortical thickness and imaging resolution, it is not possible to derive subject-specific mechanical properties on the 'vertebral shell' from imaging modalities applicable in vivo. As a first step, the goal of this study was to assess the apparent Young's modulus of vertebral cortico-cancellous bone specimens using an inverse method. A total of 22 cortico-cancellous specimens were harvested from 22 vertebral bodies. All specimens were tested in compression until failure. To compute the apparent Young's modulus of the specimen from the inverse method, the boundary conditions of the biomechanical experiments were faithfully reproduced in a finite element model (FEM), and an optimisation routine was used. The results showed a mean of the apparent Young's modulus of 374 ± 208 MPa, ranging from 87 to 791 MPa. By computing an apparent Young's modulus of a cortico-cancellous medium, this study gives mechanical data for an FEM of an entire vertebra including an external shell combining both bone tissues.

The two-compound formulation of calcipotriol and betamethasone dipropionate for treatment of moderately severe body and scalp psoriasis - an introduction

Psoriasis is a common chronic inflammatory skin disease and many patients require lifelong treatment. Characteristic scaly, itchy, unsightly psoriatic lesions affect many body areas and most patients commonly experience scalp involvement. The cosmetic embarrassment of visible body lesions, inaccessibility of scalp skin to application of therapies and proximity of sensitive facial skin add to the challenges of most patients managing their psoriasis long term. Psoriasis can severely impact patients' quality of life. This can impact significantly on the patient. In economic terms patients may incur increased out-of-pocket expenditure or extended time away from work as a direct consequence of psoriasis, particularly in severe cases; In many countries, specialist review of patients provides pressures on hard-pressed services and the costs of psoriasis care are substantial, particularly in patients with severe recalcitrant psoriasis which may require lengthy inpatient admission. Around 80% of patients with psoriasis have mild to moderately severe disease and the majority are treated with topical medicines by their physician in primary care. Despite the availability of a wide range of treatment options, regimens have been unsatisfactory, associated with patient dissatisfaction, poor compliance and often safety concerns with long-term use. Evidence-based clinical guidelines aim to improve healthcare of patients and while there are such guidelines for psoriasis, to date the challenges of (and recommendations for) managing scalp psoriasis are often limited or missing from these treatment guidelines. In the following in-journal supplement, a connected suite of five papers focus on the use of topical therapies for the treatment of the person afflicted with psoriasis. This work harnesses robust evidence from randomised clinical trials (RCTs) of topical therapies commonly used in psoriasis patients and translates this into recommendations for the most appropriate treatment of patients with body or scalp psoriasis, from an efficacy, safety and cost-effectiveness perspective. Based upon systematic review and harnessing 'state of the art' evidence assessment methodologies, the modelling work suggests that the use of a two-compound formulation (TCF) product of calcipotriol and betamethasone dipropionate is the most appropriate treatment option for both body and scalp psoriasis. This Editorial acknowledges the results of any modelling exercise have limitations; indeed such limitations are acknowledged in each modelling contribution in this issue. With these caveats in mind, this introductory paper considers the implications of this research and distillation of the evidence. This work should guide cost-effective treatment choices for body and scalp psoriasis, assist in recommendations for management of scalp psoriasis in future iterations of psoriasis clinical guidelines and help primary care physicians striving to attain best outcomes in the care of the person with psoriasis.

Transferability of model-based economic evaluations: the case of trastuzumab for the adjuvant treatment of HER2-positive early breast cancer in the Netherlands

INTRODUCTION

Geographic transferability of model-based cost-effectiveness results may facilitate and shorten the reimbursement process of new pharmaceuticals. This study provides a real world example of transferring a cost-effectiveness study of trastuzumab for the adjuvant treatment of HER2-positive early breast cancer from the United Kingdom to The Netherlands.

METHODS

Three successive steps were taken. Step 1: Collect available information with regard to the original model, and assess transferability using existing checklists. Step 2: Adapt transferability-limiting factors. Step 3: Obtain a country-specific estimate of cost-effectiveness.

RESULTS

The structure of the UK model was transferable, although some of the model inputs needed adaptation. From a health-care perspective, the Dutch estimate amounted to euro5828/quality-adjusted life-year gained. From a societal perspective, the incremental cost-effectiveness ratio was dominant.

CONCLUSION

Transferability of a model-based UK-study in three steps proved to be an efficient method to provide an early indication of the cost-effectiveness of trastuzumab and has led to the provisional reimbursement of the treatment.

[Economic concepts for measuring the costs of illness of osteoporosis: an international comparison]

Worldwide osteoporosis is underestimated and despite availability of effective and cost effective treatments, these are often not implemented. Apart from a demographically driven increase in disease cases, failure to implement or tardy implementation of preventive measures as well as poor treatment compliance leads to a deterioration of the health economic outcomes. This in turn causes considerable costs to the health care system and to society, through ineffective intake of medication, diminished quality of life and inability to work as well as substantial costs of rehabilitation of patients. Health economic analyses and methods are increasingly used by decision makers to set priorities and evaluate alternative treatment measures about their cost-effectiveness. In order to be able to capture the costs of illness incurred by osteoporosis, different diseases specific models and methods have been developed, such as the reference model of the IOF, an osteoporosis-specific Markov model or internationally comparable intervention thresholds. Health economists estimate that osteoporosis-related costs will double by 2050 in both Europe and the individual countries. For Europe this means an increase from 40 billion Euro in 2000 to almost 80 billion Euro in 2050. In Austria, an aggregation of the different costs of osteoporosis is not possible, due to a lack of comparability and availability of data. The international ICUROS study and the Austrian Osteoporosis Report 2007 are the first steps towards counteracting this situation.

The transferability of economic evaluations:testing the model of Welte

OBJECTIVE

One of the existing methods to assess the transferability of economic evaluations is the model of Welte, which is a decision-chart method that includes general and specific knockout criteria and a transferability checklist. This study aims to test Welte's model with the help of a case study.

METHODS

In this study, foreign studies were transferred to The Netherlands and then compared with a Dutch reference study. In the case study, the cost-effectiveness of physiotherapy was compared with a multidisciplinary treatment. With the help of a systematic search, several foreign studies could be identified. Based on these foreign studies, two different predictions were produced for The Netherlands. In the “all studies prediction,” all foreign studies were used. In the “Welte's model prediction,” only the foreign studies were used, which passed the general and specific knockout criteria. Both predictions were compared with the Dutch reference case.

RESULTS

A total of 14 non-Dutch studies were identified. Seven studies did not pass the general knockout criteria and one study did not pass the specific knockout criteria. As a result, 14 studies were included in the “all studies prediction” and 6 studies in the “Welte's model prediction.” The predictions yielded different results and the “Welte's model prediction” proved better on costs than the “all studies prediction.”

DISCUSSION

The application of Welte's model does influence cost and effects estimates when transferring economic data between countries. However, more cases should be subjected to the Welte transferability model before a final conclusion can be drawn.

Pharmaco-economic issues for diabetes therapy

A systematic review was undertaken to analyse pharmaco-economic issues in diabetes, with evidence selected on the basis of relevance and immediacy. Pharmaco-economics in diabetes primarily relates to making choices about antidiabetic pharmaceuticals, and this is being influenced by global trends. Trends include increasing numbers of patients with diabetes, with increasing costs of caring for people with diabetes, and an ever-present focus on the costs of pharmaceuticals which are predicted to increase as the pace of development of new medications parallels the increasing incidence of the condition. These developments have influenced the demand for health care in diabetes in the last decade, and will continue to determine this in the coming decade. Recent national experiences are cited to illustrate current issues and to focus specifically upon the challenges facing a raft of new diabetes treatment options now hitting the marketplace, although supported by fewer completed long-term trials. It can be anticipated that these newer agents will be appraised for their cost-effectiveness or value for money. Economic analyses for some of the new technologies are summarized; in general, the peer-reviewed publications using well-accepted and validated models have reported that these technologies are cost-effective. Endorsement of any technology in a national setting is not awarded simply because the incremental cost-effectiveness ratio (ICER) falls below the threshold regarded as value for money. In most national observations the reviewers expressed concerns about assumptions used in economic modelling which resulted in the ICERs being deemed optimistic at best, generally highly uncertain, and resulting in the cost-effectiveness appearing better than it really would be in clinical practice. This has often led to the authorities concluding that the price advantage of new technologies over comparators could not be justified, essentially leading to restrictions in use compared to their licence. In general, a paucity of robust evidence on longer-term outcome data together with a lack of health-related quality of life (HRQOL) data collected in a reliable manner in appropriate patients and amenable to utility (and hence quality adjusted life year or QALY) estimation have resulted in problems for these new drugs at the so-called fourth (cost-effectiveness) hurdle. In the light of these findings, the implications for generating credible fit-for-purpose cost-effectiveness analyses of new technologies in diabetes are discussed. Throughout this chapter, the interested reader is referred to a number of excellent review articles for further details.

The cost effectiveness of bisphosphonates for the prevention and treatment of osteoporosis: a structured review of the literature

Osteoporotic fragility fractures constitute a significant public health concern. The lifetime risk of any osteoporotic fracture is very high (40-50% in women and 13-22% in men). Fractures are associated with significant mortality and morbidity and represent a substantial economic burden to society. Bisphosphonates (alendronate, etidronate, risedronate and ibandronate) are indicated for the treatment and prevention of osteoporosis but are costly compared with other treatments, such as vitamin D and calcium. Our search identified 23 studies evaluating the cost effectiveness of bisphosphonate therapy for the treatment and prevention of fragility fractures; these studies were from five geographical areas and employed a variety of comparators and assumptions. We identified 11 studies investigating bisphosphonates in women with low bone mineral density (BMD) [T-score >2.5 standard deviations {SDs} below normal {mean} peak values for young adults] and previous fractures, five studies investigating bisphosphonates in women with low BMD and no previous fracture, one study of bisphosphonates in women with osteopenia, five studies involving screening and two studies of bisphosphonates in special populations (women initiating corticosteroid treatment and men). In women with low BMD and previous fractures, bisphosphonate therapy was most cost effective in populations aged > or =70 years and was unlikely to be cost effective in populations aged < or =50 years. There was uncertainty concerning the cost effectiveness of bisphosphonates in such populations aged 60-69 years. In women with low BMD without previous fractures, treatment with alendronate or risedronate appeared to be cost effective across countries (UK, US, Denmark), but there was some uncertainty about the cost effectiveness of etidronate in patients in the highest age groups. Identifying risk factors for fractures through means such as spine radiographs to detect vertebral deformities improves the cost effectiveness of treatment. In women with osteopenia, alendronate therapy may be cost effective in women with a T-score of -2.4SD in the US. Screening for low BMD and treatment with alendronate or etidronate appears to be cost effective in postmenopausal women in general and in women with rheumatoid arthritis initiating corticosteroid therapy. Alendronate therapy without screening was also shown to be potentially cost effective in certain at-risk male populations, as well as in women initiating corticosteroid therapy after the age of 40 years. Decision makers in the US, UK and Sweden should consider funding the use of bisphosphonates for the prevention and treatment of osteoporosis in women aged >70 years, particularly if they have other risk factors for fracture. Further studies are required to make more definitive conclusions in other countries and patient populations. Screening strategies for low BMD followed by bisphosphonate treatment should also be considered in the general female population aged >65 years in the UK and US and in patients with rheumatoid arthritis initiating corticosteroid therapy.

'Lost in translation': accounting for between-country differences in the analysis of multinational cost-effectiveness data

Cost-effectiveness analysis has gained status over the last 15 years as an important tool for assisting resource allocation decisions in a budget-limited environment such as healthcare. Randomised (multicentre) multinational controlled trials are often the main vehicle for collecting primary patient-level information on resource use, cost and clinical effectiveness associated with alternative treatment strategies. However, trial-wide cost effectiveness results may not be directly applicable to any one of the countries that participate in a multinational trial, requiring some form of additional modelling to customise the results to the country of interest. This article proposes an algorithm to assist with the choice of the appropriate analytical strategy when facing the task of adapting the study results from one country to another. The algorithm considers different scenarios characterised by: (a) whether the country of interest participated in the trial; and (b) whether individual patient-level data (IPD) from the trial are available. The analytical options available range from the use of regression-based techniques to the application of decision-analytic models. Decision models are typically used when the evidence base is available exclusively in summary format whereas regression-based methods are used mainly when the country of interest actively recruited patients into the trial and there is access to IPD (or at least country-specific summary data). Whichever method is used to reflect between-country variability in cost-effectiveness data, it is important to be transparent regarding the assumptions made in the analysis and (where possible) assess their impact on the study results.