Using discrete choice experiments within a cost-benefit analysis framework: some considerations

Participatory Value Evaluation (PVE): A New Preference-Elicitation Method for Decision Making in Healthcare

Participatory value evaluation (PVE) has recently been introduced in the field of health as a new method to elicit stated preferences for public policies. PVE is a method in which respondents in a choice experiment are presented with various policy options and their attributes, and are asked to compose their portfolio of preference given a public-resource constraint. This paper aims to illustrate PVE's potential for informing healthcare decision making and to position it relative to established preference-elicitation methods. We first describe PVE and its theoretical background. Next, by means of a narrative review of the eight existing PVE applications within and outside the health domain, we illustrate the different implementations of the main features of the method. We then compare PVE to several established preference-elicitation methods in terms of the structure and nature of the choice tasks presented to respondents. The portfolio-based choice task in a PVE requires respondents to consider a set of policy alternatives in relation to each other and to make trade-offs subject to one or more constraints, which more closely resembles decision making by policymakers. When using a flexible budget constraint, respondents can trade-off their private income with public expenditures. Relative to other methods, a PVE may be cognitively more demanding and is less efficient; however, it seems a promising complementary method for the preference-based assessment of health policies. Further research into the feasibility and validity of the method is required before researchers and policymakers can fully appreciate the advantages and disadvantages of the PVE as a preference-elicitation method.

Does in vitro fertilization (IVF) treatment provide good value for money? A cost-benefit analysis

Background

Using traditional health technology assessment (HTA) outcome metrics, such as quality-adjusted life-years, to assess fertility treatments raises considerable methodological challenges because the objective of fertility treatments is to create new life rather than extend, save, or improve health-related quality of life.

Objective

The aim of this study was to develop a novel cost-benefit framework to assess value for money of publicly funded IVF treatment; to determine the number of cost-beneficial treatment cycles for women of different ages; and to perform an incremental cost-benefit analysis from a taxpayer perspective.

Methods

We developed a Markov model to determine the net monetary benefit (NMB) of IVF treatment by female age and number of cycles performed. IVF treatment outcomes were monetized using taxpayers' willingness-to-pay values derived from a discrete choice experiment (DCE). Using the current funding environment as the comparator, we performed an incremental analysis of only funding cost-beneficial cycles. Similar outputs to cost-effectiveness analyses were generated, including net-benefit acceptability curves and cost-benefit planes. We created an interactive online app to provide a detailed and transparent presentation of the results.

Results

The results suggest that at least five publicly funded IVF cycles are cost-beneficial in women aged <42 years. Cost-benefit planes suggest a strong taxpayer preference for restricting funding to cost-beneficial cycles over current funding arrangements in Australia from an economic perspective.

Conclusions

The provision of fertility treatment is valued highly by taxpayers. This novel cost-benefit method overcomes several challenges of conventional cost-effectiveness methods and provides an exemplar for incorporating DCE results into HTA. The results offer new evidence to inform discussions about treatment funding arrangements.

A Benefit-Cost Analysis of BackTrack, a Multi-Component, Community-Based Intervention for High-Risk Young People in a Rural Australian Setting

BackTrack is a multi-component, community-based program designed to build capacity amongst high-risk young people. The aim of this study was to conduct a benefit-cost analysis of BackTrack, which was implemented in Armidale, a rural town in New South Wales, Australia. Costs and benefits were identified, measured and valued in 2016 Australian dollars. Costs were estimated from program financial and administrative records. Benefits were estimated using a pre-post design and conservative economic assumptions. Benefits included education attendance or completion; employment; engagement with health service providers; reduced homelessness; economic productivity; reduced vandalism to local infrastructure; reduced youth crime; reduced engagement with the justice system; and program income generated by participants. The counterfactual baseline was zero educational outcome, based on discussions with BackTrack staff and expert informants. We tested this assumption compared to the assumption that participants had a Year 8 education. There was evidence of significant quantifiable improvements in several outcomes: high school attendance or completion, vocational education attendance or completion, unskilled or vocationally qualified employment and economic productivity. Reduced homelessness, engagement with health services and acquisition of job readiness skills, as well as reduced local infrastructure vandalism and reduced crime were further quantifiable improvements. The net social benefit of BackTrack was estimated at $3,267,967 with a benefit-cost ratio of 2.03, meaning that every dollar invested in BackTrack would return $2.03 in benefits. BackTrack represents a viable funding option for a government interested in addressing the needs of high-risk young people.

Discrete choice experiment exploring women's preferences in a novel device designed to monitor the womb environment and improve our understanding of reproductive disorders

OBJECTIVES

The study aims to determine the relative importance of key attributes of a novel intrauterine device. The device monitors uterine oxygen, pH and temperature in real time with the aim of improving our understanding and treatment of reproductive disorders.

DESIGN

A discrete choice experiment was used to elicit preferences in this novel investigative tool. The attributes and levels used in the choice scenarios were length of time using the device (7, 14 or 28 days), information obtained to guide treatment (limited, majority or all cases), risk of complications (1% or 10%) and discreteness (completely discrete, moderately discrete or indiscrete).

SETTING

Secondary care hospital in Hampshire, UK.

PARTICIPANTS

361 women of reproductive age.

PRIMARY AND SECONDARY OUTCOME MEASURES

Conditional logit and latent class logit regression models to determine the preference for each attribute.

RESULTS

Conditional logit coefficients allow comparison between attributes; women placed most importance on obtaining information to guide treatment in all cases (2.771), followed by having a completely discrete device (1.104), reducing risk of complications by 1% (0.184) and decreased length of time by 1 day (0.0150). All coefficients p<0.01. Latent class conditional logit assigns participants to two classes with 27.4% in class 1 who are less likely to have higher education or qualify for National Health Service-funded in vitro fertilisation compared with class 2. Those in class 2 placed 1.7 times more importance on a device whose information guided treatment in all cases and a 1% decrease in complications risk was nearly 15 times more attractive.

CONCLUSIONS

Women placed most importance on having a device that obtains information to guide treatment and are willing to use the device for a longer, have a device with higher risk of complications and an indiscrete device if it is able to provide answers and direction for treatment of their reproductive disorder.

Exploring Community-Based Options for Reducing Youth Crime

BackTrack is a multi-component, community-based intervention designed to build capacity amongst 14–17-year-old high risk young people. The aim of the current study seeks to explore community value and preferences for reducing youth crime and improving community safety using BackTrack in a rural setting in Armidale, New South Wales, Australia. The study design used discrete choice experiments (DCEs), designed in accordance with the 10-item checklist outlined by the International Society for Pharmacoeconomics and Outcomes Research. The DCE was pilot tested on 43 participants to test feasibility and comprehension. A revised version of the survey was subsequently completed by 282 people over a 12-day period between 30 May 2016 and 10 June 2016, representing a survey response rate of 35%. Ninety per cent of respondents were residents of Armidale, the local rural town where BackTrack was implemented. The DCE generated results that consistently demonstrated a preference for social programs to address youth crime and community safety in the Armidale area. Respondents chose BackTrack over Greater Police Presence 75% of the time with an annual benefit of Australian dollars (AUD) 150 per household, equivalent to a community benefit of AUD 2.04 million. This study estimates a strong community preference for BackTrack relative to more policing (a community willing to pay equivalent to AUD 2.04 million) highlighting the clear value of including community preferences when evaluating community-based programs for high-risk young people.

Study protocol for evaluation of aid to diagnosis for developmental dysplasia of the hip in general practice: controlled trial randomised by practice

INTRODUCTION

In the UK, a compulsory '6-week hip check' is performed in primary care for the detection of developmental dysplasia of the hip (DDH). However, missed diagnoses and infants incorrectly labelled with DDH remain a problem, potentially leading to adverse consequences for infants, their families and the National Health Service. National policy states that infants should be referred to hospital if the 6-week check suggests DDH, though there is no available tool to aid examination or offer guidelines for referral. We developed standardised diagnostic criteria for DDH, based on international Delphi consensus, and a 9-item checklist that has the potential to enable non-experts to diagnose DDH in a manner approaching that of experts.

METHODS AND ANALYSIS

We will conduct a controlled trial randomised by practice that will compare a diagnostic aid against standard care for the hip check. The primary objective is to determine whether an aid to the diagnosis of DDH reduces the number of clinically insignificant referrals from primary care to hospital and the number of late diagnosed DDH. The trial will include a qualitative process evaluation, an assessment of professional behavioural change and a full health economic evaluation. We will recruit 152 general practitioner practices in England. These will be randomised to conduct the hip checks with use of the study diagnostic aid and/or as per usual practice. The total number of infants seen during a 15-month recruitment period will be 110 per practice. Two years after the 6-week hip check, we will measure the number of referred infants that are (1) clinically insignificant for DDH and (2) those that constitute appropriate referrals.

ETHICS AND DISSEMINATION

This study has approval from the Health Research Authority (16/1/2020) and the Confidentiality Advisory Group (18/2/2020). Results will be published in peer-reviewed academic journals, disseminated to patient organisations and the media.

TRIAL REGISTRATION NUMBER

NCT04101903; Pre-results.

Preferences for aspects of antenatal and newborn screening: a systematic review

BACKGROUND

Many countries offer screening programmes to unborn and newborn babies (antenatal and newborn screening) to identify those at risk of certain conditions to aid earlier diagnosis and treatment. Technological advances have stimulated the development of screening programmes to include more conditions, subsequently changing the information required and potential benefit-risk trade-offs driving participation. Quantifying preferences for screening programmes can provide programme commissioners with data to understand potential demand, the drivers of this demand, information provision required to support the programmes and the extent to which preferences differ in a population. This study aimed to identify published studies eliciting preferences for antenatal and newborn screening programmes and provide an overview of key methods and findings.

METHODS

A systematic search of electronic databases for key terms identified eligible studies (discrete choice experiments (DCEs) or best-worst scaling (BWS) studies related to antenatal/newborn testing/screening published between 1990 and October 2018). Data were systematically extracted, tabulated and summarised in a narrative review.

RESULTS

A total of 19 studies using a DCE or BWS to elicit preferences for antenatal (n = 15; 79%) and newborn screening (n = 4; 21%) programmes were identified. Most of the studies were conducted in Europe (n = 12; 63%) but there were some examples from North America (n = 2; 11%) and Australia (n = 2; 11%). Attributes most commonly included were accuracy of screening (n = 15; 79%) and when screening occurred (n = 13; 68%). Other commonly occurring attributes included information content (n = 11; 58%) and risk of miscarriage (n = 10; 53%). Pregnant women (n = 11; 58%) and healthcare professionals (n = 11; 58%) were the most common study samples. Ten studies (53%) compared preferences across different respondents. Two studies (11%) made comparisons between countries. The most popular analytical model was a standard conditional logit model (n = 11; 58%) and one study investigated preference heterogeneity with latent class analysis.

CONCLUSION

There is an existing literature identifying stated preferences for antenatal and newborn screening but the incorporation of more sophisticated design and analytical methods to investigate preference heterogeneity could extend the relevance of the findings to inform commissioning of new screening programmes.

Comparison of weighting methods used in multicriteria decision analysis frameworks in healthcare with focus on low- and middle-income countries

AIM

Criteria weighting is a key element of multicriteria decision analysis that is becoming extensively used in healthcare decision-making. In our narrative review we describe the advantages and disadvantages of various weighting methods.

METHODS

An assessment of the eight identified primary criteria weighting methods was compiled on domains including their resource requirements, and potential for bias.

RESULTS

In general, we found more complex methods to have less potential for bias; however, resource intensity and general participant burden is greater for these methods.

CONCLUSION

The selection of the most appropriate method depends on the decision-making context. The simple multiattribute rating technique (SMART) method combined with swing-weighting technique and the analytic hierarchy process methods may be the most feasible approaches for low- and middle-income countries.

Improving the Quality of Dentistry (IQuaD): a cluster factorial randomised controlled trial comparing the effectiveness and cost-benefit of oral hygiene advice and/or periodontal instrumentation with routine care for the prevention and management of periodontal disease in dentate adults attending dental primary care

BACKGROUND

Periodontal disease is preventable but remains the most common oral disease worldwide, with major health and economic implications. Stakeholders lack reliable evidence of the relative clinical effectiveness and cost-effectiveness of different types of oral hygiene advice (OHA) and the optimal frequency of periodontal instrumentation (PI).

OBJECTIVES

To test clinical effectiveness and assess the economic value of the following strategies: personalised OHA versus routine OHA, 12-monthly PI (scale and polish) compared with 6-monthly PI, and no PI compared with 6-monthly PI.

DESIGN

Multicentre, pragmatic split-plot, randomised open trial with a cluster factorial design and blinded outcome evaluation with 3 years' follow-up and a within-trial cost-benefit analysis. NHS and participant costs were combined with benefits [willingness to pay (WTP)] estimated from a discrete choice experiment (DCE).

SETTING

UK dental practices.

PARTICIPANTS

Adult dentate NHS patients, regular attenders, with Basic Periodontal Examination (BPE) scores of 0, 1, 2 or 3.

INTERVENTION

Practices were randomised to provide routine or personalised OHA. Within each practice, participants were randomised to the following groups: no PI, 12-monthly PI or 6-monthly PI (current practice).

MAIN OUTCOME MEASURES

Clinical - gingival inflammation/bleeding on probing at the gingival margin (3 years). Patient - oral hygiene self-efficacy (3 years). Economic - net benefits (mean WTP minus mean costs).

RESULTS

A total of 63 dental practices and 1877 participants were recruited. The mean number of teeth and percentage of bleeding sites was 24 and 33%, respectively. Two-thirds of participants had BPE scores of ≤ 2. Under intention-to-treat analysis, there was no evidence of a difference in gingival inflammation/bleeding between the 6-monthly PI group and the no-PI group [difference 0.87%, 95% confidence interval (CI) -1.6% to 3.3%; p = 0.481] or between the 6-monthly PI group and the 12-monthly PI group (difference 0.11%, 95% CI -2.3% to 2.5%; p = 0.929). There was also no evidence of a difference between personalised and routine OHA (difference -2.5%, 95% CI -8.3% to 3.3%; p = 0.393). There was no evidence of a difference in self-efficacy between the 6-monthly PI group and the no-PI group (difference -0.028, 95% CI -0.119 to 0.063; p = 0.543) and no evidence of a clinically important difference between the 6-monthly PI group and the 12-monthly PI group (difference -0.097, 95% CI -0.188 to -0.006; p = 0.037). Compared with standard care, no PI with personalised OHA had the greatest cost savings: NHS perspective -£15 (95% CI -£34 to £4) and participant perspective -£64 (95% CI -£112 to -£16). The DCE shows that the general population value these services greatly. Personalised OHA with 6-monthly PI had the greatest incremental net benefit [£48 (95% CI £22 to £74)]. Sensitivity analyses did not change conclusions.

LIMITATIONS

Being a pragmatic trial, we did not deny PIs to the no-PI group; there was clear separation in the mean number of PIs between groups.

CONCLUSIONS

There was no additional benefit from scheduling 6-monthly or 12-monthly PIs over not providing this treatment unless desired or recommended, and no difference between OHA delivery for gingival inflammation/bleeding and patient-centred outcomes. However, participants valued, and were willing to pay for, both interventions, with greater financial value placed on PI than on OHA.

FUTURE WORK

Assess the clinical effectiveness and cost-effectiveness of providing multifaceted periodontal care packages in primary dental care for those with periodontitis.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN56465715.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 38. See the NIHR Journals Library website for further project information.

Development of an index to define overall disease severity in IBD

BACKGROUND AND AIM

Disease activity for Crohn's disease (CD) and UC is typically defined based on symptoms at a moment in time, and ignores the long-term burden of disease. The aims of this study were to select the attributes determining overall disease severity, to rank the importance of and to score these individual attributes for both CD and UC.

METHODS

Using a modified Delphi panel, 14 members of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) selected the most important attributes related to IBD. Eighteen IOIBD members then completed a statistical exercise (conjoint analysis) to create a relative ranking of these attributes. Adjusted utilities were developed by creating proportions for each level within an attribute.

RESULTS

For CD, 15.8% of overall disease severity was attributed to the presence of mucosal lesions, 10.9% to history of a fistula, 9.7% to history of abscess and 7.4% to history of intestinal resection. For UC, 18.1% of overall disease severity was attributed to mucosal lesions, followed by 14.0% for impact on daily activities, 11.2% C reactive protein and 10.1% for prior experience with biologics. Overall disease severity indices were created on a 100-point scale by applying each attribute's average importance to the adjusted utilities.

CONCLUSIONS

Based on specialist opinion, overall CD severity was associated more with intestinal damage, in contrast to overall UC disease severity, which was more dependent on symptoms and impact on daily life. Once validated, disease severity indices may provide a useful tool for consistent assessment of overall disease severity in patients with IBD.

Results of the First Steps study: a randomised controlled trial and economic evaluation of the Group Family Nurse Partnership (gFNP) programme compared with usual care in improving outcomes for high-risk mothers and their children and preventing abuse

Background

Family Nurse Partnership (FNP) is a home-based nurse home-visiting programme to support vulnerable parents. Group Family Nurse Partnership (gFNP) has similar aims and materials and was demonstrated to be feasible in implementation evaluations.

Objectives

To determine whether or not gFNP, compared with usual care, could reduce risk factors for maltreatment in a vulnerable group and be cost-effective.

Design

A multisite randomised controlled parallel-group trial and prospective economic evaluation, with eligible women allocated (minimised by site and maternal age group) to gFNP or usual care.

Setting

Community locations in the UK.

Participants

Expectant mothers aged < 20 years with one or more previous live births, or expectant mothers aged 20–24 years with no previous live births and with low educational qualifications (defined as General Certificate of Education at grade C or higher in neither mathematics nor English language or, if they had both, no more than four General Certificates of Education at grade C or higher).

Intervention

Forty-four sessions of gFNP (14 during pregnancy and 30 in the first 12 months after birth) were offered to groups of between 8 and 12 women with similar expected delivery dates (the difference between the earliest and latest expected delivery date ranged from 8 to 10 weeks depending on the group) by two family nurses (FNs), one of whom had notified her intention to practise as a midwife.

Main outcome measures

Parenting was assessed by a self-report measure of parenting opinions, the Adult Adolescent Parenting Inventory Version 2 (AAPI-2), and an objective measure of maternal sensitivity, the CARE-Index. Cost-effectiveness was primarily expressed in terms of incremental cost per quality-adjusted life-year (QALY) gained.

Data sources

Interviews with participants at baseline and when infants were aged 2, 6 and 12 months. Cost information from nurse weekly logs and other service delivery data.

Results

In total, 166 women were enrolled (99 to the intervention group and 67 to the control group). Adjusting for site and maternal age group, the intention-to-treat analysis found no effect of gFNP on either of the primary outcomes. AAPI-2 total was 7.5/10 [standard error (SE) 0.1] in both arms [difference also adjusted for baseline 0.08, 95% confidence interval (CI) –0.15 to 0.28;p = 0.50]. CARE-Index maternal sensitivity mean: intervention 4.0 (SE 0.3); control 4.7 (SE 0.4) (difference –0.76, 95% CI –1.67 to 0.13;p = 0.21). The sensitivity analyses supported the primary analyses. The probability that the gFNP intervention was cost-effective based on the QALY measure did not exceed 3%. However, in terms ofchangein AAPI-2 score (baseline to 12 months), the probability that gFNP was cost-effective reached 25.1%. A separate discrete choice experiment highlighted the value placed by both pregnant women and members of the general population on non-health outcomes that were not included in the QALY metric.

Limitations

Slow recruitment resulted in smaller than ideal group sizes. In some cases, few or no sessions took place owing to low initial group size, and small groups may have contributed to attrition from the intervention. Exposure to gFNP sessions was below maximum for most group members, with only 58 of the 97 intervention participants receiving any sessions; FNs were experienced with FNP but were mainly new to delivering gFNP.

Conclusions

The trial does not support the delivery of gFNP as a means of reducing the risk of child abuse or neglect in this population.

Future work

A randomised controlled trial with modified eligibility to enable first-time mothers aged < 20 years to be included, and a modified recruitment strategy to enable faster identification of potential participants from antenatal medical records.

Trial registration

Current Controlled Trials ISRCTN78814904.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full inPublic Health Research; Vol. 5, No. 9. See the NIHR Journals Library website for further project information.

Discrete choice experiments of pharmacy services: a systematic review

Background Two previous systematic reviews have summarised the application of discrete choice experiments to value preferences for pharmacy services. These reviews identified a total of twelve studies and described how discrete choice experiments have been used to value pharmacy services but did not describe or discuss the application of methods used in the design or analysis. Aims (1) To update the most recent systematic review and critically appraise current discrete choice experiments of pharmacy services in line with published reporting criteria and; (2) To provide an overview of key methodological developments in the design and analysis of discrete choice experiments. Methods The review used a comprehensive strategy to identify eligible studies (published between 1990 and 2015) by searching electronic databases for key terms related to discrete choice and best-worst scaling (BWS) experiments. All healthcare choice experiments were then hand-searched for key terms relating to pharmacy. Data were extracted using a published checklist. Results A total of 17 discrete choice experiments eliciting preferences for pharmacy services were identified for inclusion in the review. No BWS studies were identified. The studies elicited preferences from a variety of populations (pharmacists, patients, students) for a range of pharmacy services. Most studies were from a United Kingdom setting, although examples from Europe, Australia and North America were also identified. Discrete choice experiments for pharmacy services tended to include more attributes than non-pharmacy choice experiments. Few studies reported the use of qualitative research methods in the design and interpretation of the experiments (n = 9) or use of new methods of analysis to identify and quantify preference and scale heterogeneity (n = 4). No studies reported the use of Bayesian methods in their experimental design. Conclusion Incorporating more sophisticated methods in the design of pharmacy-related discrete choice experiments could help researchers produce more efficient experiments which are better suited to valuing complex pharmacy services. Pharmacy-related discrete choice experiments could also benefit from more sophisticated analytical techniques such as investigations into scale and preference heterogeneity. Employing these sophisticated methods for both design and analysis could extend the usefulness of discrete choice experiments to inform health and pharmacy policy.

Toward a Hedonic Value Framework in Health Care

In well-functioning markets, a hedonic pricing scheme can reflect the marginal valuation of various attributes of a differentiated product at market equilibrium. It serves as an important tool to inform pricing of a new product with a specific combination of attributes. Because health cannot be bought and sold in a market setting, and health care markets are distorted by insurance or government subsidies, direct valuation of a health intervention as a differentiated good through observed market prices is difficult. In this article, we discuss the rationale of using stated preference methods for developing a hedonic value framework for health insurance products to inform the decision on whether a product should be covered or subsidized by insurance, given its price. This value index will not reflect marginal value at market equilibrium, as in a hedonic pricing scheme, but would capture the distribution of marginal value in the population. We discuss how affordability concerns can be integrated into the development of a hedonic valuation model. We compare this framework with traditional cost-effectiveness analysis and also the existing value frameworks put forth by various organizations. The framework can be adopted to inform other decisions such as pricing. We argue that developing such a comprehensive and decision-theoretic value framework is feasible and, if successful, can serve to inform health care resource allocation in this country for decades to come in a systematic manner.

Health-related quality of life in Parkinson's: impact of 'off' time and stated treatment preferences

PURPOSE

Long-term levodopa therapy and related fluctuating plasma concentrations are associated with between-dose periods of 'off time' resulting in substantial variation in symptoms and functioning throughout the day in people with Parkinson's (PwP).

METHODS

PwP across UK, France, Spain and Italy completed an online survey to explore: the impact of 'off time' on (1) health-related quality of life (HRQL) and (2) on functioning and ability to undertake usual activities; (3) the value of 'off time' relative to other factors associated with Parkinson's through a stated preference discrete choice experiment (SPDCE).

RESULTS

In total, 305 PwP completed the online survey. Overall mean HRQL (utility) score was significantly lower for 'off time' (0.37) than for 'on time' (0.60). All attributes within the SPDCE were significant predictors of treatment choice, although increased duration of 'on time' (per hour per day: odds ratio (OR) = 1.40) and predictability of 'off time' to within 30 min (OR = 1.42) were valued most highly.

CONCLUSIONS

'On time' and predictability of 'off time' are highly valued by PwP. Due to substantial diurnal variation of Parkinson's symptoms, standard patient-reported outcome (PRO) assessments may not adequately capture the impact of 'off time' on HRQL and participation in daily activities.

Preferences for a third-trimester ultrasound scan in a low-risk obstetric population: a discrete choice experiment

OBJECTIVE

Establish maternal preferences for a third-trimester ultrasound scan in a healthy, low-risk pregnant population.

DESIGN

Cross-sectional study incorporating a discrete choice experiment.

SETTING

A large, urban maternity hospital in Northern Ireland.

PARTICIPANTS

One hundred and forty-six women in their second trimester of pregnancy.

METHODS

A discrete choice experiment was designed to elicit preferences for four attributes of a third-trimester ultrasound scan: health-care professional conducting the scan, detection rate for abnormal foetal growth, provision of non-medical information, cost. Additional data collected included age, marital status, socio-economic status, obstetric history, pregnancy-specific stress levels, perceived health and whether pregnancy was planned. Analysis was undertaken using a mixed logit model with interaction effects.

MAIN OUTCOME MEASURES

Women's preferences for, and trade-offs between, the attributes of a hypothetical scan and indirect willingness-to-pay estimates.

RESULTS

Women had significant positive preference for higher rate of detection, lower cost and provision of non-medical information, with no significant value placed on scan operator. Interaction effects revealed subgroups that valued the scan most: women experiencing their first pregnancy, women reporting higher levels of stress, an adverse obstetric history and older women.

CONCLUSIONS

Women were able to trade on aspects of care and place relative importance on clinical, non-clinical outcomes and processes of service delivery, thus highlighting the potential of using health utilities in the development of services from a clinical, economic and social perspective. Specifically, maternal preferences exhibited provide valuable information for designing a randomized trial of effectiveness and insight for clinical and policy decision makers to inform woman-centred care.

An Integrated Epidemiological and Economic Analysis of Vaccination against Highly Pathogenic Porcine Reproductive and Respiratory Syndrome (PRRS) in Thua Thien Hue Province, Vietnam

The purposes of this study are to assess pig farmers' preference for highly pathogenic porcine reproductive and respiratory syndrome (PRRS) vaccine, and estimate the cost and benefit of PRRS vaccination in Vietnam. This study employed an integrated epidemiological and economic analysis which combined susceptible-infectious-recovered (SIR) model, choice experiment (CE) and cost-benefit analysis (CBA) together. The result of SIR model showed the basic reproduction number (R0) of PRRS transmission in this study is 1.3, consequently, the optimal vaccination percentage is 26%. The results of CE in this study indicate that Vietnam pig farmers are showing a high preference for the PRRS vaccine. However, their mean willingness to pay is lower than the potential cost of PRRS vaccine. It can be considered to be one of the reasons that the PRRS vaccination ratio is still low in Vietnam. The results of CBA specified from the whole society's point of view (Social perspective), the benefits of PRRS vaccination are 2.3 to 4.5 times larger than the costs. To support policy making for increasing the PRRS vaccination proportion, this study indicates two ways to increase the vaccination proportion: i) decrease vaccine price by providing a subsidy, ii) provide compensation of culling only for PRRS vaccinated pigs.

The use of discrete choice experiments to inform health workforce policy: a systematic review

BACKGROUND

Discrete choice experiments have become a popular study design to study the labour market preferences of health workers. Discrete choice experiments in health, however, have been criticised for lagging behind best practice and there are specific methodological considerations for those focused on job choices. We performed a systematic review of the application of discrete choice experiments to inform health workforce policy.

METHODS

We searched for discrete choice experiments that examined the labour market preferences of health workers, including doctors, nurses, allied health professionals, mid-level and community health workers. We searched Medline, Embase, Global Health, other databases and grey literature repositories with no limits on date or language and contacted 44 experts. Features of choice task and experimental design, conduct and analysis of included studies were assessed against best practice. An assessment of validity was undertaken for all studies, with a comparison of results from those with low risk of bias and a similar objective and context.

RESULTS

Twenty-seven studies were included, with over half set in low- and middle-income countries. There were more studies published in the last four years than the previous ten years. Doctors or medical students were the most studied cadre. Studies frequently pooled results from heterogeneous subgroups or extrapolated these results to the general population. Only one third of studies included an opt-out option, despite all health workers having the option to exit the labour market. Just five studies combined results with cost data to assess the cost effectiveness of various policy options. Comparison of results from similar studies broadly showed the importance of bonus payments and postgraduate training opportunities and the unpopularity of time commitments for the uptake of rural posts.

CONCLUSIONS

This is the first systematic review of discrete choice experiments in human resources for health. We identified specific issues relating to this application of which practitioners should be aware to ensure robust results. In particular, there is a need for more defined target populations and increased synthesis with cost data. Research on a wider range of health workers and the generalisability of results would be welcome to better inform policy.

Introduction to health economics and decision-making: Is economics relevant for the frontline clinician?

In a climate of escalating demands for new health care services and significant constraints on new resources, the disciplines of health economics and health technology assessment (HTA) have increasingly been turned to as explicit evidence-based frameworks to help make tough health care access and reimbursement decisions. Health economics is the discipline of economics concerned with the efficient allocation of health care resources, essentially trying to maximize health benefits to society contingent upon available resources. HTA is a broader field drawing upon several disciplines, but which relies heavily upon the tools of health economics and economic evaluation. Traditionally, health economics and economic evaluation have been widely used at the political (macro) and local (meso) decision-making levels, and have progressively had an important role even at informing individual clinical decisions (micro level). The aim of this paper is to introduce readers to health economics and discuss its relevance to frontline clinicians. Particularly, the content of the paper will facilitate clinicians' understanding of the link between economics and their medical practice, and how clinical decision-making reflects on health care resource allocation.

Discrete choice experiments in pharmacy: a review of the literature

Objective

Discrete choice experiments (DCEs) have been widely used to elicit patient preferences for various healthcare services and interventions. The aim of our study was to conduct an in-depth scoping review of the literature and provide a current overview of the progressive application of DCEs within the field of pharmacy.

Methods

Electronic databases (MEDLINE, EMBASE, SCOPUS, ECONLIT) were searched (January 1990–August 2011) to identify published English language studies using DCEs within the pharmacy context. Data were abstracted with respect to DCE methodology and application to pharmacy.

Key findings

Our search identified 12 studies. The DCE methodology was utilised to elicit preferences for different aspects of pharmacy products, therapy or services. Preferences were elicited from either patients or pharmacists, with just two studies incorporating the views of both. Most reviewed studies examined preferences for process-related or provider-related aspects with a lesser focus on health outcomes. Monetary attributes were considered to be important by most patients and pharmacists in the studies reviewed. Logit, probit or multinomial logit models were most commonly employed for estimation.

Conclusion

Our study showed that the pharmacy profession has adopted the DCE methodology consistent with the general health DCEs although the number of studies is quite limited. Future studies need to examine preferences of both patients and providers for particular products or disease-state management services. Incorporation of health outcome attributes in the design, testing for external validity and the incorporation of DCE results in economic evaluation framework to inform pharmacy policy remain important areas for future research.

Developing adolescent-specific health state values for economic evaluation: an application of profile case best-worst scaling to the Child Health Utility 9D

BACKGROUND

The way that health is measured and valued is fundamental to economic evaluation. To date, adult health state values have been routinely used in the calculation of QALYs for the economic evaluation of healthcare treatment and preventive programmes, including those targeted at adolescents.

OBJECTIVES

The main objective of this study was to apply profile case best-worst scaling (BWS) discrete-choice experiment (DCE) methods to obtain adolescent-specific values for the Child Health Utility 9D (CHU9D), a new generic preference-based measure of health-related quality of life developed specifically for application in cost-effectiveness analyses of treatments and interventions targeted at young people. A secondary aim was to assess the feasibility of a web-based method of data collection for the valuation of health states defined by the CHU9D.

METHODS

A web-based survey was developed including the CHU9D instrument and a series of BWS DCE questions. Specifically, respondents were asked to indicate the best and worst attribute levels from a series of ten health states defined by the CHU9D, presented one at a time. The survey was administered to a community-based sample of consenting adolescents (n = 590) aged 11-17 years. A conditional logistic regression model was applied to estimate values (part-worth utilities) for each level of the nine attributes relating to the CHU9D. A marginal utility matrix was then estimated to generate an adolescent-specific scoring algorithm on the full health = 1 and dead = 0 scale required for the calculation of QALYs.

RESULTS

The results indicate that participants were able to readily choose 'best' and 'worst' attribute levels for the CHU9D health states. Large differences in value were found between the first and fifth levels (indicating 'no problems' and 'severe problems', respectively) for all nine attributes relating to the CHU9D. In general, there was little differentiation between the middle levels of all attributes indicating only limited additional value for adolescents of moving between these levels. Comparison of the adolescent-specific algorithm and the existing adult scoring algorithm for the CHU9D revealed some significant differences in values for identical health states, which may have important implications for the application of the CHU9D to value adolescent treatment and service programmes particularly for mental health. In general, adolescents appeared to place more weight upon the CHU9D attributes relating to mental health (worried, sad and annoyed) than would be implied by application of the existing algorithm based upon adult values.

CONCLUSION

This study provides preliminary indications that there may be potentially important and systematic differences in the valuations attached to identical health states by adolescents in comparison with adult population groups. The study findings lend support to the potential future application of profile case BWS DCE methods to undertake large-scale health state valuation studies directly with young adolescent population samples and provide support for the feasibility and acceptability of a web-based mode of administration for this purpose.

Combining individual-level discrete choice experiment estimates and costs to inform health care management decisions about customized care: the case of follow-up strategies after breast cancer treatment

OBJECTIVE

Customized care can be beneficial for patients when preferences for health care programs are heterogeneous. Yet, there is little guidance on how individual-specific preferences and cost data can be combined to inform health care decisions about customized care. Therefore, we propose a discrete choice experiment-based approach that illustrates how to analyze the cost-effectiveness of customized (and noncustomized) care programs to provide information for hospital managers.

METHODS

We exploit the fact that choice models make it possible to determine whether preference heterogeneity exists and to obtain individual-specific parameter estimates. We present an approach of how to combine these individual-specific parameter estimates from a random parameter model (mixed logit model) with cost data to analyze the cost-effectiveness of customized care and demonstrate our method in the case of follow-up after breast cancer treatment.

RESULTS

We found that there is significant preference heterogeneity for all except two attributes of breast cancer treatment follow-up and that the fully customized care program leads to higher utility and lower costs than the current standardized program. Compared with the single alternative program, the fully customized care program has increased benefits and higher costs. Thus, it is necessary for health care decision makers to judge whether the use of resources for customized care is cost-effective.

CONCLUSIONS

Decision makers should consider using the results obtained from our methodological approach when they consider implementing customized health care programs, because it may help to find ways to save costs and increase patient satisfaction.

Discrete choice experiments in health economics: a review of the literature

Discrete choice experiments (DCEs) have become a commonly used instrument in health economics. This paper updates a review of published papers between 1990 and 2000 for the years 2001-2008. Based on this previous review, and a number of other key review papers, focus is given to three issues: experimental design; estimation procedures; and validity of responses. Consideration is also given to how DCEs are applied and reported. We identified 114 DCEs, covering a wide range of policy questions. Applications took place in a broader range of health-care systems, and there has been a move to incorporating fewer attributes, more choices and interview-based surveys. There has also been a shift towards statistically more efficient designs and flexible econometric models. The reporting of monetary values continues to be popular, the use of utility scores has not gained popularity, and there has been an increasing use of odds ratios and probabilities. The latter are likely to be useful at the policy level to investigate take-up and acceptability of new interventions. Incorporation of interactions terms in the design and analysis of DCEs, explanations of risk, tests of external validity and incorporation of DCE results into a decision-making framework remain important areas for future research.

Eliciting willingness to pay in obstetrics: comparing a direct and an indirect valuation method for complex health outcomes

OBJECTIVE

To compare direct and indirect willingness to pay (WTP) elicitation methods in terms of feasibility, reliability, and comparability. The application is obstetrics, where always both a mother's and a child's health are at stake.

METHODS

An open-ended contingent valuation method (CVM) as a direct WTP elicitation method, and the discrete choice experiment (DCE) as an indirect WTP elicitation method. Vignettes to be valued were based on clinical patient data. Participants were 88 laypersons who received their questionnaires by postal mail.

RESULTS

The DCE task was completed faster (p=0.006) and was regarded easier (p<0.001) than the CVM task. Test-retest for CVM was substantial (ICC=0.76), and for DCE moderate (k=0.49). Female sex (p<0.001), age≥50 years (p=0.013), higher income (p<0.001), and higher education (p<0.001) were associated with higher WTP. Correlation between CVM and DCE was 0.79 (Kendall's Tau-b; p<0.001). The implied WTP as derived with DCE was between 2.3 and 10.2 times higher than with CVM. The relationship between the WTPs was linear.

CONCLUSION

It is yet unclear what lies behind the numbers of DCE. DCE has no methodological benefits over the conventional CVM when eliciting WTP for complex health outcomes in obstetrics.

Healthy-days time equivalents for outcomes of acute rotavirus infections

Rotavirus is the most common cause of severe gastroenteritis in infants and young children worldwide. Health-state utility measures used in economic evaluations of rotavirus vaccines do not reflect differences between mild and severe symptoms of rotavirus gastroenteritis and, therefore, do not adequately capture preferences for non-fatal outcomes associated with rotavirus common in industrialized countries. This paper describes the development and results of a survey specifically designed to develop quality-adjusted time equivalents for rotavirus gastroenteritis among a sample of parents with young children in the United States as an alternative to conventional QALY measures in assessing cost-effectiveness.

Does the inclusion of a cost attribute result in different preferences for the surgical treatment of primary basal cell carcinoma?: a comparison of two discrete-choice experiments

BACKGROUND

Nowadays, an increasing number of discrete-choice experiments (DCEs) incorporate cost as an attribute. However, the inclusion of a cost attribute, particularly within collectively funded healthcare systems, can be challenging because health services or goods are generally not traded in a market situation and individuals are not used to paying for a service or a good at the point of consumption.

OBJECTIVE

To examine whether the inclusion of a cost attribute in a DCE results in different preferences regarding a surgical treatment for primary basal cell carcinoma (BCC) compared with a DCE without a cost attribute.

METHODS

A randomized study was performed in which the impact of a cost attribute on the general public's preferences for a surgical treatment (Mohs micrographic surgery [MMS] or standard excision [SE]) to remove BCC was examined. This was done by comparing the outcomes of two DCEs, one with a cost attribute (DCE_cost) and one without (DCE_nocost). Six attributes (recurrence, re-excision, travel time, surgical time, waiting time for surgical results, costs) and their levels were selected, based on results of a clinical trial, a cost-effectiveness study, a review and a focus group of patients who had recently received treatment for BCC. Outcomes of both DCEs were compared in terms of theoretical validity, relative importance of the attributes and the rank order of preferences.

RESULTS

A total of 615 respondents (n = 303 for DCE_nocost; n = 312 for DCE_cost) were interviewed by telephone. This gave an overall response rate of 38%. Respondents in DCE_nocost preferred a surgical treatment with a lower probability of recurrence, lower surgery time, lower waiting time and no risk for a re-excision. Respondents in DCE_cost showed the same preferences, but also preferred a treatment with less travel time and lower costs. Overall, respondents in both DCEs showed the same preference for a surgical treatment: MMS was preferred over SE.

CONCLUSION

Results suggest that, in this population, the inclusion of a cost attribute in a DCE leads to the same preference regarding a surgical treatment to remove BCC as a DCE without a cost attribute. However, further research in different settings is needed to confirm these findings.

Choice experiments in health: the good, the bad, the ugly and toward a brighter future

Compared to many applied areas of economics, health economics has a strong tradition in eliciting and using stated preferences (SP) in policy analysis. Discrete choice experiments (DCEs) are one SP method increasingly used in this area. Literature on DCEs in health and more generally has grown rapidly since the mid-1990s. Applications of DCEs in health have come a long way, but to date few have been ‘best practice’, in part because ‘best practice’ has been somewhat of a moving target. The purpose of this paper is to briefly survey the history of DCEs and the state of current knowledge, identify and discuss knowledge gaps, and suggest potentially fruitful areas for future research to fill such gaps with the aim of moving the application of DCEs in health economics closer to best practice.

Eliciting individual preferences for health care: a case study of perinatal care

OBJECTIVE

To demonstrate how a discrete choice experiment (DCE) can be used to elicit individuals' preferences for health care and how these preferences can be incorporated into a cost-benefit analysis.

METHODS

A DCE which elicited preferences for three perinatal services: specialist nurse appointments; home visits from a trained lay visitor; and home-help. Cost was included to obtain a monetary measure of the value that individuals place on the services. In total, 292 women who had previously participated in a randomized trial of alternative forms of pre-natal care were interviewed.

RESULTS

The most preferred service configuration consisted of three nurse appointments and two home visits before birth and 4 h of home-help per week for the first 4 weeks after birth. On average, women are willing to pay $371 for this package. A package that excluded home-help was valued at $122 whilst provision of three nurse appointments only was valued at $97. The predicted uptake of the services ranged from 37% to 93% depending on the woman's experience with the service, whether or not it was her first child and her level of education.

CONCLUSION

The willingness to pay values were much higher than the costs for nurse appointments, suggesting this service produces a net social benefit. The willingness to pay for the package including both the nurse appointments and home visits only just exceeded the costs of the package, suggesting there is a relatively high chance that this package produces a net social loss.

A review of the application and contribution of discrete choice experiments to inform human resources policy interventions

Although the factors influencing the shortage and maldistribution of health workers have been well-documented by cross-sectional surveys, there is less evidence on the relative determinants of health workers' job choices, or on the effects of policies designed to address these human resources problems. Recently, a few studies have adopted an innovative approach to studying the determinants of health workers' job preferences. In the absence of longitudinal datasets to analyse the decisions that health workers have actually made, authors have drawn on methods from marketing research and transport economics and used Discrete Choice Experiments to analyse stated preferences of health care providers for different job characteristics. We carried out a literature review of studies using discrete choice experiments to investigate human resources issues related to health workers, both in developed and developing countries. Several economic and health systems bibliographic databases were used, and contacts were made with practitioners in the field to identify published and grey literature. Ten studies were found that used discrete choice experiments to investigate the job preferences of health care providers. The use of discrete choice experiments techniques enabled researchers to determine the relative importance of different factors influencing health workers' choices. The studies showed that non-pecuniary incentives are significant determinants, sometimes more powerful than financial ones. The identified studies also emphasized the importance of investigating the preferences of different subgroups of health workers. Discrete choice experiments are a valuable tool for informing decision-makers on how to design strategies to address human resources problems. As they are relatively quick and cheap survey instruments, discrete choice experiments present various advantages for informing policies in developing countries, where longitudinal labour market data are seldom available. Yet they are complex research instruments requiring expertise in a number of different areas. Therefore it is essential that researchers also understand the potential limitations of discrete choice experiment methods.

Economic methods for valuing the outcomes of genetic testing: beyond cost-effectiveness analysis

Genetic testing in health care can provide information to help with disease prediction, diagnosis, prognosis, and treatment. Assessing the clinical utility of genetic testing requires a process to value and weight different outcomes. This article discusses the relative merits of different economic measures and methods to inform recommendations relative to genetic testing for risk of disease, including cost-effectiveness analysis and cost-benefit analysis. Cost-effectiveness analyses refer to analyses that calculate the incremental cost per unit of health outcomes, such as deaths prevented or life-years saved because of some intervention. Cost-effectiveness analyses that use preference-based measures of health state utility such as quality-adjusted life-years to define outcomes are referred to as cost-utility analyses. Cost-effectiveness analyses presume that health policy decision makers seek to maximize health subject to resource constraints. Cost-benefit analyses can incorporate monetary estimates of willingness-to-pay for genetic testing, including the perceived value of information independent of health outcomes. These estimates can be derived from contingent valuation or discrete choice experiments. Because important outcomes of genetic testing do not fit easily within traditional measures of health, cost-effectiveness analyses do not necessarily capture the full range of outcomes of genetic testing that are important to decision makers and consumers. We recommend that health policy decision makers consider the value to consumers of information and other nonhealth attributes of genetic testing strategies.

Balancing patient preferences and clinical needs: community versus hospital based care for patients with suspected DVT

OBJECTIVE

To establish patients' preferences and willingness to pay (WTP) for different service models for suspected deep vein thrombosis (DVT).

METHODS

We analysed patient responses to a discrete choice experiment (DCE) questionnaire which had been targeted at patients in Leicester, UK. The questionnaire elicited preferences/WTP for attributes of DVT provision including speed of diagnosis; access; continuity of care; and minimizing hospital visits. Additionally we evaluated trade-offs between clinical and service attributes. We analysed responses from 256 patients with suspected DVT (65% response rate).

RESULTS

Respondents are WTP pound 4.82 per extra hour of dedicated DVT service provision; pound 17.12 per hospital visit avoided; pound 115.73 per day's reduction in diagnostic wait; and pound 179.32 for 'much' not 'some' continuity, or pound 56.88 for 'some' not 'lack' of continuity in nursing.

CONCLUSIONS

Research evaluating different DVT service models usually reports on clinical efficacy in centres of excellence. Results show prompt diagnosis is valued by patients and may improve efficacy by reducing unnecessary anticoagulation. However, patients value 'process' measures such as continuity of care also. To ensure optimal provision, clinical benefit measurement ought to be augmented with information on patients' preferences.

Willingness to accept versus willingness to pay in a discrete choice experiment

OBJECTIVES

Our main objective was to compare willingness to accept (WTA) and willingness to pay (WTP) in a discrete choice experiment on hearing aid provision. Additionally, income effect and endowment effect were explored as possible explanations for the disparity between WTA and WTP, and the impact of using a WTA and/or WTP format to elicit monetary valuations on the net benefit of the new organization of hearing aid provision was examined.

METHODS

Choice sets were based on five attributes: performer of the initial assessment; accuracy of the initial assessment; duration of the pathway; follow-up at the ear, nose, and throat specialist; and costs. Persons with hearing complaints randomly received a WTP (costs defined as extra payment) or WTA (costs defined as discount) version of the experiment. In the versions, except for the cost attribute, all choice sets were equal.

RESULTS

The cost coefficient was statistically significantly higher in the WTP format. Marginal WTA was statistically significantly higher than marginal WTP for the attributes accuracy and follow-up. Disparity was higher in the high educational (as proxy for income) group. We did not find proof of an experience endowment effect. Implementing the new intervention would only be recommended when using WTP.

CONCLUSIONS

WTA exceeds WTP, also in a discrete choice experiment. As this affects monetary valuations, more research on when to use a payment or a discount in the cost attribute is needed before discrete choice results can be used in cost-benefit analyses.

Conducting discrete choice experiments to inform healthcare decision making: a user's guide

Discrete choice experiments (DCEs) are regularly used in health economics to elicit preferences for healthcare products and programmes. There is growing recognition that DCEs can provide more than information on preferences and, in particular, they have the potential to contribute more directly to outcome measurement for use in economic evaluation. Almost uniquely, DCEs could potentially contribute to outcome measurement for use in both cost-benefit and cost-utility analysis. Within this expanding remit, our intention is to provide a resource for current practitioners as well as those considering undertaking a DCE, using DCE results in a policy/commercial context, or reviewing a DCE. We present the fundamental principles and theory underlying DCEs. To aid in undertaking and assessing the quality of DCEs, we discuss the process of carrying out a choice study and have developed a checklist covering conceptualizing the choice process, selecting attributes and levels, experimental design, questionnaire design, pilot testing, sampling and sample size, data collection, coding of data, econometric analysis, validity, interpretation and welfare and policy analysis. In this fast-moving area, a number of issues remain on the research frontier. We therefore outline potentially fruitful areas for future research associated both with DCEs in general, and with health applications specifically, paying attention to how the results of DCEs can be used in economic evaluation. We also discuss emerging research trends. We conclude that if appropriately designed, implemented, analysed and interpreted, DCEs offer several advantages in the health sector, the most important of which is that they provide rich data sources for economic evaluation and decision making, allowing investigation of many types of questions, some of which otherwise would be intractable analytically. Thus, they offer viable alternatives and complements to existing methods of valuation and preference elicitation.