Modelling Informal Carers' Health-Related Quality of Life: Challenges for Economic Evaluation.

There has been increasing interest in including carers' health-related qualify of life (HRQoL) in decision models, but currently there is no best practice guidance as to how to do so. Models thus far have typically assumed that carers' HRQoL can be predicted from patient health states, as we illustrate with three examples of disease-modifying treatments. However, this approach limits the mechanisms that influence carers' HRQoL solely to patient health and may not accurately reflect carers' outcomes. In this article, we identify and discuss challenges associated with modelling intervention effects on carers' HRQoL: attaching carer utilities to patient disease states, the size of the caring network, aggregation of carer and patient HRQoL, patient death, and modelling longer-term carer HRQoL. We review and critique potential alternatives to modelling carers' HRQoL in decision models: trial-based analyses, qualitative consideration, cost-consequence analysis, and multicriteria decision analysis, noting that each of these also has its own challenges. We provide a framework of issues to consider when modelling carers' HRQoL and suggest how these can be addressed in current practice and future research.

Recommendations for Emerging Good Practice and Future Research in Relation to Family and Caregiver Health Spillovers in Health Economic Evaluations: A Report of the SHEER Task Force.

BACKGROUND: Omission of family and caregiver health spillovers from the economic evaluation of healthcare interventions remains common practice. When reported, a high degree of methodological inconsistency in incorporating spillovers has been observed. AIM: To promote emerging good practice, this paper from the Spillovers in Health Economic Evaluation and Research (SHEER) task force aims to provide guidance on the incorporation of family and caregiver health spillovers in cost-effectiveness and cost-utility analysis. SHEER also seeks to inform the basis for a spillover research agenda and future practice. METHODS: A modified nominal group technique was used to reach consensus on a set of recommendations, representative of the views of participating subject-matter experts. Through the structured discussions of the group, as well as on the basis of evidence identified during a review process, recommendations were proposed and voted upon, with voting being held over two rounds. RESULTS: This report describes 11 consensus recommendations for emerging good practice. SHEER advocates for the incorporation of health spillovers into analyses conducted from a healthcare/health payer perspective, and more generally inclusive perspectives such as a societal perspective. Where possible, spillovers related to displaced/foregone activities should be considered, as should the distributional consequences of inclusion. Time horizons ought to be sufficient to capture all relevant impacts. Currently, the collection of primary spillover data is preferred and clear justification should be provided when using secondary data. Transparency and consistency when reporting on the incorporation of health spillovers are crucial. In addition, given that the evidence base relating to health spillovers remains limited and requires much development, 12 avenues for future research are proposed. CONCLUSIONS: Consideration of health spillovers in economic evaluations has been called for by researchers and policymakers alike. Accordingly, it is hoped that the consensus recommendations of SHEER will motivate more widespread incorporation of health spillovers into analyses. The developing nature of spillover research necessitates that this guidance be viewed as an initial roadmap, rather than a strict checklist. Moreover, there is a need for balance between consistency in approach, where valuable in a decision making context, and variation in application, to reflect differing decision maker perspectives and to support innovation.

Modelling Spillover Effects on Informal Carers: The Carer QALY Trap.

The provision of informal (unpaid) care can impose significant 'spillover effects' on carers, and accounting for these effects is consistent with the efficiency and equity objectives of health technology assessment (HTA). Inclusion of these effects in health economic models, particularly carer health-related quality of life (QOL), can have a substantial impact on net quality-adjusted life year (QALY) gains and the relative cost effectiveness of new technologies. Typically, consideration of spillover effects improves the value of a technology, but in some circumstances, consideration of spillover effects can lead to situations whereby life-extending treatments for patients may be considered cost ineffective due to their impact on carer QOL. In this piece we revisit the classic 'QALY trap' and introduce an analogous 'carer QALY trap' which may have practical implications for economic evaluations where the inclusion of carer QOL reduces incremental QALY gains. Such results may align with a strict QALY-maximisation rule, however we consider the extent to which this principle may be at odds with the preferences of carers themselves (and possibly society more broadly), potentially leading decision makers into the carer QALY trap as a result. We subsequently reflect on potential solutions, highlighting the important (albeit limited) role that deliberation has to play in HTA.

Carers' Health-Related Quality of Life in Global Health Technology Assessment: Guidance, Case Studies and Recommendations.

Including health outcomes for carers as well as patients in economic evaluations can change the results and conclusions of the analysis. Whilst in many disease areas there can be clear justification for including carers' health-related quality of life (HRQL) in health technology assessments (HTAs), we believe that, in general, the perspective of carers is under-represented in HTA. We were interested in the extent, and methods by which, HTA bodies include carers' HRQL in economic evaluation. We reviewed guidance from 13 HTA bodies across the world regarding carers' HRQL. We examined five interventions, as case studies, assessed by different HTA bodies, and extracted information on whether carers' HRQL was included by the manufacturers or assessors in their dossiers of evidence, the data and methods used, and the impact on the results. We developed recommendations to guide analysts on including carers' HRQL in economic evaluations. When reviewing the methods guides: two bodies recommend including carers' HRQL in the base case, two referred to outcomes for all individuals, two preferred to exclude carers, three said it depended on other conditions, and it was unclear for four. Across the five case studies: five source studies for carers' HRQL and two different modelling approaches were used. Including carers' HRQL increased incremental quality-adjusted life-years (QALYs) in 19/23 analyses (decreased it in two); there was substantial variation in the magnitude of change. We recommend: (1) the inclusion of carers is clearly justified, (2) the use of HRQL data from the population under comparison where possible, (3) the use of data from another disease area or country is clearly justified (and transferability/applicability issues are discussed), (4) the use of external data to derive comparisons for cross-sectional data is justified, (5) assumptions and implications of the modelling approach are explicit, and (6) disaggregated results for patients and carers are presented.

Systematic Review of Cost-Utility Analyses That Have Included Carer and Family Member Health-Related Quality of Life.

OBJECTIVES: Health interventions for patients can also affect the health of their informal carers and family members. These changes in carer or family member health could be reflected in cost-utility analyses (CUAs) through the inclusion of their quality-adjusted life-years (QALYs). We conducted a systematic review to identify and describe all CUAs that have included family member health-related QALYs. METHODS: A total of 4 bibliographic databases were searched from inception to July 2021. A 2-stage sifting process for inclusion of studies was undertaken. We performed data extraction using a standardized data extraction form and performed a narrative synthesis of the evidence. RESULTS: A total of 40 CUAs published between 1999 and 2021 were identified. CUAs were conducted in 15 different countries. CUAs examined 13 different conditions including 15 CUAs on vaccination, 5 on Alzheimer's disease, 2 on Parkinson's disease, 3 on dementia, and 2 on terminal illness. The EQ-5D was the most commonly used measure of family member health. Generally, including carer QALYs resulted in lower incremental cost-effectiveness ratios. CONCLUSIONS: When considering the total number of economic evaluations published, few have included family member QALYs and the methods for doing so are often inconsistent and data sources often limited. Estimation of family member QALYs in patient CUAs was regularly uncertain and often substantial in magnitude. The findings highlight the variation among methods and call for greater consistency in methods for incorporating family member QALYs in patient CUAs.

Out of Date or Best Before? A Commentary on the Relevance of Economic Evaluations Over Time.

The impact of time on the applicability and relevance of historical economic evaluations can be considerable. Ignoring this may lead to the use of weak or invalid evidence to inform important research questions or resource allocation decisions, as historical economic evaluations may have reached different conclusions compared to if a similar study had been conducted more recently. There are multiple factors that contribute towards evidence becoming outdated including changes to the relevant decision problem (e.g. comparators), changes to parameters (such as costs, utilities and resource use) and methodological updates (e.g. recommendations on uncertainty analysis). Researchers reviewing economic evaluations need to consider whether changes over time would influence the study design and results if the evaluation were repeated, to the extent that it is no longer helpful or informative. In this paper, we summarise these key issues and make recommendations about how and whether researchers can future proof their economic evaluations.

Cost Effectiveness of Ranibizumab vs Aflibercept vs Bevacizumab for the Treatment of Macular Oedema Due to Central Retinal Vein Occlusion: The LEAVO Study.

BACKGROUND: We aimed to assess the cost effectiveness of intravitreal ranibizumab (Lucentis), aflibercept (Eylea) and bevacizumab (Avastin) for the treatment of macular oedema due to central retinal vein occlusion. METHODS: We calculated costs and quality-adjusted life-years from the UK National Health Service and Personal Social Services perspective. We performed a within-trial analysis using the efficacy, safety, resource use and health utility data from a randomised controlled trial (LEAVO) over 100 weeks. We built a discrete event simulation to model long-term outcomes. We estimated utilities using the Visual-Functioning Questionnaire-Utility Index, EQ-5D and EQ-5D with an additional vision question. We used standard UK costs sources for 2018/19 and a cost of £28 per bevacizumab injection. We discounted costs and quality-adjusted life-years at 3.5% annually. RESULTS: Bevacizumab was the least costly intervention followed by ranibizumab and aflibercept in both the within-trial analysis (bevacizumab: £6292, ranibizumab: £13,014, aflibercept: £14,328) and long-term model (bevacizumab: £18,353, ranibizumab: £30,226, aflibercept: £35,026). Although LEAVO did not demonstrate bevacizumab to be non-inferior for the visual acuity primary outcome, the three interventions generated similar quality-adjusted life-years in both analyses. Bevacizumab was always the most cost-effective intervention at a threshold of £30,000 per quality-adjusted life-year, even using the list price of £243 per injection. CONCLUSIONS: Wider adoption of bevacizumab for the treatment of macular oedema due to central retinal vein occlusion could result in substantial savings to healthcare systems and deliver similar health-related quality of life. However, patients, funders and ophthalmologists should be fully aware that LEAVO could not demonstrate that bevacizumab is non-inferior to the licensed agents.

A Review of the Psychometric Performance of Selected Child and Adolescent Preference-Based Measures Used to Produce Utilities for Child and Adolescent Health.

OBJECTIVE: This review examined the psychometric performance of 4 generic child- and adolescent-specific preference-based measures that can be used to produce utilities for child and adolescent health. METHODS: A systematic search was undertaken to identify studies reporting the psychometric performance of the Child Health Utility (CHU9D), EQ-5D-Y (3L or 5L), and Health Utilities Index Mark 2 (HUI2) or Mark 3 (HUI3) in children and/or adolescents. Data were extracted to assess known-group validity, convergent validity, responsiveness, reliability, acceptability, and feasibility. Data were extracted separately for the dimensions and utility index where this was reported. RESULTS: The review included 76 studies (CHU9D n = 12, EQ-5D-Y-3L n = 20, HUI2 n = 26,HUI3 n = 43), which varied considerably across conditions and sample size. EQ-5D-Y-3L had the largest amount of evidence of good psychometric performance in proportion to the number of studies examining performance. The majority of the evidence related to EQ-5D-Y-3L was based on dimensions. CHU9D was assessed in fewer studies, but the majority of studies found evidence of good psychometric performance. Evidence for HUI2 and HUI3 was more mixed, but the studies were more limited in sample size and statistical power, which was likely to have affected performance. CONCLUSIONS: The heterogeneity of published studies means that the evidence is based on studies across a range of countries, populations and conditions, using different study designs, different languages, different value sets and different statistical techniques. Evidence for CHU9D in particular is based on a limited number of studies. The findings raise concerns about the comparability of self-report and proxy-report responses to generate utility values for children and adolescents.

Inclusion of Carer Health-Related Quality of Life in National Institute for Health and Care Excellence Appraisals.

OBJECTIVES: Health interventions for patients can have effects on their carers too. For consistency, decision makers may wish to specify whether carer outcomes should be included. One example is the National Institute for Health and Care Excellence (NICE), whose reference case specifies that economic evaluations should include direct health effects for patients and carers where relevant. We aimed to review the methods used in including carer health-related quality of life (HRQL) in NICE appraisals. METHODS: We reviewed all published technology appraisals (TAs) and highly specialized technologies (HSTs) to identify those that included carer HRQL and discussed the methods and data sources. RESULTS: Twelve of 414 TAs (3%) and 4 of 8 HSTs (50%) included carer HRQL in cost-utility analyses. Eight were for multiple sclerosis, the remainder were each in a unique disease area. Twelve of the 16 appraisals modeled carer HRQL as a function of the patient's health state, 3 modeled carer HRQL as a function of the patient's treatment, and 1 included family quality-adjusted life year (QALY) loss. They used 5 source studies: 2 compared carer EQ-5D scores with controls, 2 measured carer utility only (1 health utilities index and 1 EQ-5D), and 1 estimated family QALY loss from a child's death. Two used disutility estimates not from the literature. Including carer HRQL increased the incremental QALYs and decreased incremental cost-effectiveness ratios in all cases. CONCLUSIONS: The inclusion of carer HRQL in NICE appraisals is relatively uncommon and has been limited by data availability.

How health inequalities accumulate and combine to affect treatment value: A distributional cost-effectiveness analysis of smoking cessation interventions.

INTRODUCTION: Reduction of health inequality is a goal in health policy, but commissioners lack information on how policies change health inequality. This study illustrates how decision models can be readily extended to produce information on health inequality impacts as well as for population health, using the example of smoking cessation therapies. METHODS: We retrospectively adapt a model developed for public health guidance to undertake distributional cost effectiveness analysis. We identify and incorporate evidence on how inputs vary by area-level deprivation. Therapies are evaluated in terms of total population health, extent of inequality, and a summary measure of equally distributed equivalent health based on a societal value for inequality aversion. Last, we examine how accounting for social variation in different sets of parameters affects our results. RESULTS: All interventions increase population health and increase the slope index ofinequality. At estimated levels of health inequality aversion for England, our resultsindicate that the increases in inequality are compensated by the health gains. DISCUSSION: The inequality impacts are driven by higher benefits of quitting and higher intervention uptake amongst advantaged groups, despite the greater proportion of smokers in disadvantaged groups. Failure to account for differential effects between groups leadsto different conclusions about health inequality impact but does not alter conclusionsabout value for money.

A Review of the Methods Used to Generate Utility Values in NICE Technology Assessments for Children and Adolescents.

OBJECTIVE: This review summarizes and critically examines methods used to generate utilities for child and adolescent health states in previous National Institute for Health and Care Excellence (NICE) technology assessments (TA) and highly specialized technology (HST) evaluations. METHODS: We identified all NICE TA and HST evaluations in which the licensed indication for the technology included people younger than 18 and included in the review all evaluations using a cost-utility analysis. RESULTS: The review includes 40 TA and HST evaluations. Most assessments generated utility values with the EQ-5D scored using the adult version of the EQ-5D either exclusively (n = 16) or alongside other utility measures and direct elicitation methods of patient own utility (n = 17), although 7 did not use the EQ-5D. Eight assessments used both the EQ-5D child- and adolescent-specific preference-based measures: Health Utilities Index Mark 2 (n = 6), child- and adolescent-specific preference-based measure for atopic dermatitis (n = 1), and youth version of the EQ-5D (EQ-5D-Y) valued using the adult EQ-5D value set (n = 1) or generated using mapping and valued using the adult EQ-5D value set (n = 2). Some cost-utility analyses used age adjustment (utility subtractions, weights, and published mapping formulae) from the adult EQ-5D UK population norms to reflect the general population or disease-free health for children and adolescents (n = 9), and 1 assessment assumed full health (utility value of 1). CONCLUSION: The review found limited use of child and adolescent population-specific measures to generate health state utility values for children and adolescents in NICE technology assessments. Often assessments involve the use of an adult-specific measure to reflect the health of children.

Mapping From Visual Acuity to EQ-5D, EQ-5D With Vision Bolt-On, and VFQ-UI in Patients With Macular Edema in the LEAVO Trial.

OBJECTIVES: Mappings to convert clinical measures to preference-based measures of health such as the EQ-5D-3L are sometimes required in cost-utility analyses. We developed mappings to convert best-corrected visual acuity (BCVA) to the EQ-5D-3L, the EQ-5D-3L with a vision bolt-on (EQ-5D V), and the Visual Functioning Questionnaire-Utility Index (VFQ-UI) in patients with macular edema caused by central retinal vein occlusion. METHODS: We used data from Lucentis, Eylea, Avastin in vein occlusion (LEAVO), which is a phase-3 randomized controlled trial comparing ranibizumab, aflibercept, and bevacizumab in 463 patients with observations at 6 time points. We estimated adjusted limited dependent variable mixture models consisting of 1 to 4 distributions (components) using BCVA in each eye, age, and sex to predict utility within the components and BCVA as a determinant of component membership. We compared model fit using mean error, mean absolute error, root mean square error, Akaike information criteria, Bayesian information criteria, and visual inspection of mean predicted and observed utilities and cumulative distribution functions. RESULTS: Mean utility scores were 0.82 for the EQ-5D-3L, 0.79 for the EQ-5D V, and 0.88 for the VFQ-UI. The best-fitting models for the EQ-5D and EQ-5D V had 2 components (with means of approximately 0.44 and 0.85), and the best-fitting model for VFQ-UI had 3 components (with means of approximately 0.95, 0.74, and 0.90). CONCLUSIONS: Models with multiple components better predict utility than those with single components. This article provides a valuable addition to the literature, in which previous mappings in visual acuity have been limited to linear regressions, resulting in unfounded assumptions about the distribution of the dependent variable.

Evaluation of Intervention Impact on Health Inequality for Resource Allocation.

INTRODUCTION: We describe a simplified distributional cost-effectiveness analysis based on aggregate data to estimate the health inequality impact of public health interventions. METHODS: We extracted data on costs, health outcomes expressed as quality-adjusted life years (QALYs), and target populations for interventions within National Institute for Health and Care Excellence (NICE) public health guidance published up to October 2016. Evidence on variation by age, gender, and index of multiple deprivation informed socioeconomic distributions of incremental QALYs, health opportunity costs, and the baseline distribution of health. Total population QALYs, summary measures of inequality, and a health equity impact plane show results by intervention and by guideline. A value for inequality aversion from a general population survey in England let us combine impacts on health inequality and total health into a single measure of intervention value. RESULTS: Our estimates suggest that of 134 interventions considered by NICE, 70 (52%) reduce inequality and increase health, 21 (16%) involve a tradeoff between improving health and improving health inequality, and 43 (32%) reduce health and increase health inequality. Fully implemented, the potential impact of all recommendations was 23,336,181 additional QALYs for the population of England and Wales and a reduction of the gap in quality-adjusted life expectancy between the healthiest and least healthy from 13.78 to 13.34 QALYs. The combined value of the additional health and reduction in inequality was 28,723,776 QALYs. DISCUSSION: Our analysis takes account of the fact that existing public health spending likely benefits the most disadvantaged. This simple method applied separately to economic evaluation produces evidence of intervention impacts on the distribution of health that is vital in determining value for money when health inequality reduction is a policy goal.

The Impact of Moving from EQ-5D-3L to -5L in NICE Technology Appraisals.

BACKGROUND: The EuroQol-5 Dimension (EQ-5D) instrument is the National Institute for Health and Care Excellence (NICE)'s preferred measure of health-related quality of life (QoL) in adults. The three-level (3L) value set is currently recommended for use, but the five-level (5L) set is increasingly being used in practice. OBJECTIVE: We aimed to explore the impact of moving from 3L to 5L in NICE appraisals. METHODS: We adapted our existing mapping for use with health state utility values derived from a population where the original distribution of utilities was unknown. We used this mapping to estimate 5L utilities for 21 comparisons of interventions from models used in NICE technology appraisal decision making, covering a range of disease areas. RESULTS: All utilities increased using 5L, and the differences between highest and lowest utilities decreased. In ten oncology comparisons, using 5L generally increased the incremental quality-adjusted life-years (QALYs) as the benefit from improving survival increased. In four non-oncology comparisons where the intervention improved QoL only, the incremental QALYs decreased as the benefit of improving QoL was reduced. In seven non-oncology comparisons where interventions improved survival and QoL, there was a trade-off between increasing the benefit from survival and decreasing the benefit from improving QoL. CONCLUSION: 3L and 5L lead to substantially different estimates of incremental QALYs and cost effectiveness. The direction and magnitude of the change is not consistent across case studies. Using 5L instead of 3L may lead to different reimbursement decisions. NICE will face inconsistencies in decision making if it uses 3L and 5L concurrently.

Dinutuximab Beta for Treating Neuroblastoma: An Evidence Review Group and Decision Support Unit Perspective of a NICE Single Technology Appraisal.

As part of its Single Technology Appraisal (STA) process, the UK National Institute for Health and Care Excellence (NICE) invited the manufacturer (EUSA Pharma) of dinutuximab beta (Qarziba®) to submit evidence of its clinical and cost effectiveness for treating neuroblastoma. The BMJ Technology Assessment Group (BMJ-TAG) was commissioned to act as the Evidence Review Group (ERG), reviewing the submission from the company. The Decision Support Unit (DSU) was commissioned to review additional evidence submitted by the company and to undertake further analyses. This article presents the critical review of the company's submissions by the ERG and DSU, further analyses undertaken by the DSU, and the outcome of the NICE guidance. The clinical effectiveness for dinutuximab beta was derived from a phase III randomised controlled trial (RCT) that assessed the safety and efficacy of the addition of interleukin (IL)-2 to dinutuximab beta plus isotretinoin. This trial did not inform the relative effectiveness of dinutuximab beta versus isotretinoin alone, which was established practice in the UK for maintenance treatment. In the absence of direct evidence, the company initially conducted a naïve indirect treatment comparison against a historical control, and later performed a matching-adjusted indirect comparison (MAIC) against the isotretinoin arm of an RCT comparing dinutuximab alpha and isotretinoin. The company submitted a partitioned survival analysis model that calculated the incremental cost effectiveness of dinutuximab beta versus isotretinoin. The company's original incremental cost-effectiveness ratio (ICER) was £22,338 per quality-adjusted life-year (QALY) gained. However, the ERG were concerned that the company's ICER was not suitable for decision making, and thus carried out initial exploratory analysis as a first step to overcome the naïve estimation of treatment effectiveness in the model. The ERG's analysis estimated an ICER of £111,858 per QALY gained. In their revised analysis incorporating the MAIC and other changes as requested by the appraisal committee, the company's ICER was £24,661 per QALY gained. When the DSU incorporated longer-term isotretinoin data and made corrections to the model, the ICER increased to between £62,886 and £87,164 per QALY gained depending on the choice of survival model. A confidential Patient Access Scheme (PAS) decreased the ICERs. The ICERs with the PAS were over £40,000 per QALY gained, but the NICE committee additionally considered the patient population and its size, the disease severity, the potential for significant survival benefit and uncaptured health benefits, and recommended dinutuximab beta as a treatment option, subject to the company providing the agreed discount in the PAS.

Smoking Cessation: A Comparison of Two Model Structures.

BACKGROUND: Most economic evaluations of smoking cessation interventions have used cohort state-transition models. Discrete event simulations (DESs) have been proposed as a superior approach. OBJECTIVE: We developed a state-transition model and a DES using the discretely integrated condition event (DICE) framework and compared the cost-effectiveness results. We performed scenario analysis using the DES to explore the impact of alternative assumptions. METHODS: The models estimated the costs and quality-adjusted life years (QALYs) for the intervention and comparator from the perspective of the UK National Health Service and Personal Social Services over a lifetime horizon. The models considered five comorbidities: chronic obstructive pulmonary disease, myocardial infarction, coronary heart disease, stroke and lung cancer. The state-transition model used prevalence data, and the DES used incidence. The costs and utility inputs were the same between two models and consistent with those used in previous analyses for the National Institute for Health and Care Excellence. RESULTS: In the state-transition model, the intervention produced an additional 0.16 QALYs at a cost of £540, leading to an incremental cost-effectiveness ratio (ICER) of £3438. The comparable DES scenario produced an ICER of £5577. The ICER for the DES increased to £18,354 when long-term relapse was included. CONCLUSIONS: The model structures themselves did not influence smoking cessation cost-effectiveness results, but long-term assumptions did. When there is variation in long-term predictions between interventions, economic models need a structure that can reflect this.

The cost-effectiveness of seven behavioural interventions to prevent drug misuse in vulnerable populations.

BACKGROUND: The National Institute for Health and Care Excellence (NICE) developed a guideline on drug misuse prevention in vulnerable populations. Part of the guideline development process involved evaluating cost-effectiveness and determining which interventions represented good value for money. METHODS: Economic models were developed for seven interventions which aimed to prevent drug use in vulnerable populations. The models compared the costs (to the health and crime sectors) and health benefits (in quality-adjusted life years (QALYs)) of each intervention and its comparator. Sensitivity analysis explored the uncertainty associated with the cost of each intervention and duration of its effect. RESULTS: The reduction in drug use for each intervention partly offset the costs of the intervention, and improved health outcomes (QALYs). However, with high intervention costs and low QALY gains, none of the interventions were estimated to be cost-effective in the base case. Sensitivity analysis found that some of the interventions could be cost-effective if they could be delivered at a lower cost, or if the effect could be sustained for more than two years. CONCLUSIONS: For drug misuse prevention to be prioritised by funders, the consequences of drug misuse need to be understood, and interventions need to be shown to be effective and cost-effective. Quantifying the wider harms of drug misuse and wider benefits of prevention interventions poses challenges in evaluating the cost-effectiveness of drug misuse prevention interventions. A greater understanding of the consequences of drug misuse and causal factors could facilitate development of cost-effective interventions to prevent drug misuse.

The Cost Effectiveness of Lubiprostone in Chronic Idiopathic Constipation.

OBJECTIVE: The objective of this study was to evaluate the cost effectiveness of lubiprostone, prucalopride, placebo and immediate referral to secondary care in chronic idiopathic constipation (CIC) in an economic model that was used by the UK National Institute for Health and Care Excellence (NICE) in developing guidance. METHODS: We developed a cohort state-transition model to reflect the treatment pathway in CIC from the UK NHS and personal social services perspective. Time on treatment was determined by a treatment continuation rule using data from an indirect comparison and survival curves fitted to long-term data. Quality of life was defined by whether CIC was resolved or unresolved, using published values. Costs were determined by drug acquisition costs, invasive procedures and healthcare resource use (associated with resolved or unresolved CIC), using published UK sources. Deterministic and probabilistic sensitivity analyses were conducted. RESULTS: Over a 10-year time horizon, lubiprostone was more costly and more effective than placebo and immediate referral to secondary care, with incremental cost-effectiveness ratios (ICERs) of £58,979 and £21,152. Lubiprostone dominated prucalopride in the base case and with a time horizon of 1 year. The main sensitivity for the comparison against placebo was the assumptions around placebo cost and efficacy. The main sensitivity for the comparison against prucalopride was the endpoint used in the indirect comparison. CONCLUSION: Lubiprostone may be cost effective compared with prucalopride or immediate referral but not compared with placebo in the base case. The implementation of the guidance issued by NICE should increase quality of life for patients with CIC and provide a further treatment option.