Patient preferences for managing asthma: results from a discrete choice experiment

Vaccine decision making in New Zealand: a discrete choice experiment

BACKGROUND

Vaccine hesitancy is a significant threat to global health. A key part of addressing hesitancy is to ensure that public health messaging prioritises information that is considered important to the public. This study aimed to examine how different vaccine characteristics affect public preferences for vaccines in New Zealand, what trade-offs they are willing to make between different vaccine characteristics, and how their preferences are affected by their vaccine-related conspiracy beliefs and COVID-19 vaccination status.

METHODS

An online discrete choice experiment (DCE) was designed to elicit individual preferences about vaccines using the 1000minds platform. Members of the general population of New Zealand aged ≥ 18 years were invited to complete the DCE. Participants were asked to indicate their preference between two options showing different combinations of vaccine characteristics. Data on sociodemographic characteristics were collected. Beliefs were measured using the vaccine conspiracy beliefs scale (VCBS) with scores ≥ 19 indicating strong vaccine-related conspiracy beliefs. The DCE was analysed using the PAPRIKA method (Potentially All Pairwise RanKings of all possible Alternatives) and preferences compared between respondents with high versus low VCBS scores and vaccinated versus unvaccinated respondents for COVID-19.

RESULTS

A total of 611 respondents from 15 regions completed the DCE. Mean (SD) age was 45.9 (14.7) years with most having had 2 or more doses of the coronavirus vaccine (86%). Mean (SD) VCBS score was 18.5 (12.4) indicating moderate vaccine-related conspiracy beliefs. Risk of severe adverse effects was the most highly valued vaccine characteristic, followed by vaccine effectiveness and duration of protection. Vaccine origin and route of administration were ranked least important. Respondents scoring high on the VCBS placed less value on the effectiveness of vaccines but greater value on development time and total number of doses (p < 0.001). COVID-19 unvaccinated respondents ranked development time and total number of doses more highly than those vaccinated respondents (p < 0.001).

CONCLUSIONS

Risk of severe adverse effects, vaccine effectiveness and duration of protection were rated by the New Zealand public as the top three most important vaccine characteristics. This information is important for informing public health messaging to promote vaccine uptake and inform vaccine decision-making.

Priority setting in the German healthcare system: results from a discrete choice experiment

Worldwide, social healthcare systems must face the challenges of a growing scarcity of resources and of its inevitable distributional effects. Explicit criteria are needed to define the boundaries of public reimbursement decisions. As Germany stands at the beginning of such a discussion, more formalised priority setting procedures seem in order. Recent research identified multi-criteria decision analysis (MCDA) as a promising approach to inform and to guide decision-making in healthcare systems. In that regard, this paper aims to analyse the relative weight assigned to various criteria in setting priority interventions in Germany. A discrete choice experiment (DCE) was employed in 2015 to elicit equity and efficiency preferences of 263 decision makers, through six attributes. The experiment allowed us to rate different policy interventions based on their features in a composite league table (CLT). As number of potential beneficiaries, severity of disease, individual health benefits and cost-effectiveness are the most relevant criteria for German decision makers within the sample population, the results display an overall higher preference towards efficiency criteria. Specific high priority interventions are mental disorders and cardiovascular diseases.

What are the job attribute preferences of physicians and nurses in Türkiye? Evidence from a discrete choice experiment

BACKGROUND

In Türkiye, as in other countries, the maldistribution of the health workforce is a serious concern. Although policymakers have developed various incentive packages, this problem has not been thoroughly addressed yet. Discrete choice experiment (DCE) is a valuable method to provide evidence-based information for these incentive packages to attract healthcare staff for rural jobs. The main aim of this study is to investigate the stated preferences of physicians and nurses when choosing a job region.

METHODS

A labelled DCE was conducted to assess job preferences of physicians and nurses from two hospitals one of which is urban, and the other is in a rural region in Türkiye Job attributes included wage, creche, infrastructure, workload, education opportunity, housing, and career opportunity. Mixed logit model was used to analyse the data.

RESULTS

The strongest attribute associated with job preferences was region (coefficient - 3.06, [SE 0.18]) for physicians (n = 126) and wages (coefficient 1.02, [SE 0.08]) for nurses (n = 218). According to the Willingness to Pay (WTP) calculations, while the physicians claimed 8627 TRY (1,813 $), the nurses claimed 1407 TRY (296 $) in addition to their monthly salaries to accept a rural job.

CONCLUSION

Both financial and non-financial factors did affect the preferences of physicians and nurses. These DCE results provide information for policymakers about what characteristics might increase the motivation of physicians and nurses to work in rural areas in Türkiye.

Public and decision-maker stated preferences for pharmaceutical subsidy decisions in Iran: an application of the discrete choice experiment

Background

The argument about funding criteria poses challenges for health decision-makers in all countries. This study aimed to investigate the public and decision-maker preferences for pharmaceutical subsidy decisions in Iran.

Methods

A discrete choice experiment (DCE) was used for eliciting the preferences of the public and decision-makers. Four attributes including health gain after treatment, the severity of the disease, prevalence of the disease, and monthly out of pocket and relevant levels were designed in the form of hypothetical scenarios. The analysis was done by using conditional logit analysis.

Results

The results show all of four attributes are important for pharmaceutical subsidy decisions. But a medicine that improves health gain after treatment is more likely to be a choice in subsidy decisions (by relative importance of 28% for public and 42% for decision-makers). Out of pocket, severity, and prevalence of disease subsequently influence the preferences of the public and decision-makers, respectively. The greatest difference is observed in changing the health gain after treatment and out of pocket levels, between public and decision-makers.

Conclusion

This research reveals that the public is willing and able to provide preferences to inform policymakers for pharmaceutical decision-making; it also sets grounds for further studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40545-021-00365-0.

A Systematic and Critical Review of Discrete Choice Experiments in Asthma and Chronic Obstructive Pulmonary Disease

Background

Regulators have called for greater emphasis on the role of the patient voice to inform medical product development and decision making, and expert guidelines and reports for asthma and chronic obstructive pulmonary disease (COPD) both explicitly recommend the consideration of patient preferences in the management of these diseases. Discrete choice experiments (DCEs) are commonly used to quantify stakeholders’ treatment preferences and estimate the trade-offs they are willing to make between outcomes such as treatment benefits and risks.

Objective

The aim of this systematic literature review is to provide an up-to-date and critical review of DCEs published in asthma and COPD; specifically, we aim to evaluate the subject of preference studies conducted in asthma and COPD, what attributes have been included, stakeholders’ preferences, and the consistency in reporting of instrument development, testing and reporting of results.

Methods

A systematic review of published DCEs on asthma and COPD treatments was conducted using Embase, Medline and the Cochrane Database of Systematic Reviews. Studies were included if they included a DCE conducted in a relevant population (e.g. patients with asthma or COPD or their caregivers, asthma or COPD-treating clinicians, or the general population), and reported quantitative outcomes on participants’ preferences. Study characteristics were summarised descriptively, and descriptive analyses of attribute categories, consistency in reporting on key criteria, and stakeholder preferences were undertaken.

Results

A total of 33 eligible studies were identified, including 28 unique DCEs. The majority (n = 20; 71%) of studies were conducted in a patient sample. Studies focused on inhaler treatments, and included attributes in five key categories: symptoms and treatment benefits (n = 23; 82%), treatment convenience (n = 19; 68%), treatment cost (n = 17; 61%), treatment risks (n = 13; 46%), and other (n = 10; 36%). Symptoms and treatment benefits were the attributes most frequently ranked as important to patients (n = 26, 72%), followed by treatment risks (n = 7, 39%). Several studies (n = 9, 32%) did not qualitatively pre-test their DCE, and a majority did not report the uncertainty in estimated outcomes (n = 18; 64%).

Conclusions

DCEs in asthma and COPD have focused on treatment benefits and convenience, with less evidence generated on participants’ risk tolerance. Quality criteria and reporting standards are needed to promote study quality and ensure consistency in reporting between studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40271-021-00536-w.

What matters to people with severe asthma? Exploring add-on asthma medication and outcomes of importance

There is an increasing number of new therapies for severe asthma; however, what outcomes people with severe asthma would like improved and what aspects they prioritise in new medications remain unknown. This study aimed to understand what outcomes are important to patients when prescribed new treatments and to determine the characteristics of importance to patients in their choice of asthma treatments.

Participants with severe asthma (n=50) completed a cross-sectional survey that ranked 17 potential hypothetical outcomes of treatment using a seven-point Likert scale, as well as selecting their top five overall outcomes. Participants also completed hypothetical scenarios trading off medication characteristics for four hypothetical add-on asthma treatments.

Participants (58% male), had a mean±sd age of 62.2±13.5 years. Their top three prioritised outcomes were: to improve overall quality of life (selected by 83% of people), reduce number and severity of asthma attacks (72.3%), and being able to participate in physical activity (59.6%) When trading off medication characteristics, the majority of patients with severe asthma chose the hypothetical medication with the best treatment efficacy (68%). However, a subgroup of patients prioritised the medication's side-effect profile and mode of delivery to select their preferred medication.

People with severe asthma value improved quality of life as an important outcome of treatment. Shared decision-making discussions between clinicians and patients that centre around medication efficacy and side-effect profile can incorporate patient preferences for add-on therapy in severe asthma.

Improving quality of life is an important treatment outcome. Shared decision-making discussions between clinicians and patients that centre around efficacy and side-effect profile incorporate patient preferences for add-on therapy in severe asthma.https://bit.ly/2GY1Sc4

An international discrete choice experiment assessing patients' preferences for disease-modifying therapy attributes in multiple sclerosis

Aim: This discrete choice experiment aimed to assess patients' preferences for treatment attributes in multiple sclerosis (MS). Patients & methods: Patients with relapsing-remitting MS completed an online survey assessing treatment preferences. Descriptive statistical analysis and discrete choice hierarchical Bayesian modeling were performed. Results: Across the overall sample (n = 485), dosing regimen, efficacy and safety were equally important. Within the whole sample, and among those diagnosed <10 years ago, intravenous infusion ≤3 times/year was the preferred dosing regimen; among patients diagnosed ≥10 years ago it was preferred equally to oral treatments. Patients were more willing to accept frequent but mild over rare but severe side effects. Conclusion: Several factors influence patient preferences for MS treatments and must be considered in patient-centered care.

What matters most to patients when choosing treatment for mild-moderate asthma? Results from a discrete choice experiment

BACKGROUND

An as-needed combination preventer and reliever regimen was recently introduced as an alternative to conventional daily preventer treatment for mild asthma. In a subgroup analysis of the PRACTICAL study, a pragmatic randomised controlled trial of budesonide-formoterol reliever therapy versus maintenance budesonide plus terbutaline reliever therapy in adults with mild asthma, we recently reported that about two-thirds preferred as-needed combination preventer and reliever therapy. The aim of this study was to determine the relative importance of attributes associated with these two asthma therapies in this subgroup of participants who indicated their preferred treatment in the PRACTICAL study.

METHODS

At their final study visit, a subgroup of participants indicated their preferred treatment and completed a discrete choice experiment using the Potentially All Pairwise RanKings of all possible Alternatives method and 1000minds software. Treatment attributes and their levels were selected from measurable study outcomes, and included: treatment regimen, shortness of breath, steroid dose and likelihood of asthma flare-up.

RESULTS

The final analysis dataset included 288 participants, 64% of whom preferred as-needed combination preventer and reliever. Of the attributes, no shortness of breath and lowest risk of asthma flare-up were ranked highest and second highest, respectively. However, the relative importance of the other two attributes varied by preferred therapy: treatment regimen was ranked higher by participants who preferred as-needed treatment than by participants who preferred maintenance treatment.

CONCLUSIONS

Knowledge of patient preferences for treatment attributes together with regimen characteristics can be used in shared decision-making regarding choice of treatment for patients with mild-moderate asthma.

TRIAL REGISTRATION NUMBER

ACTRN12616000377437.

Targeting the cancer lesion, not the whole prostate

Modern cancer treatment aims to conserve as much healthy tissue as possible. This has been challenging in the treatment of prostate cancer due to the difficulty in imaging the gland and concerns over leaving multifocal cancer untreated. With improvements in imaging and understanding of multifocal prostate cancer evidence now shows accurate treatment of just the primary focus of cancer or the index lesion can control progression or recurrence of the disease. Many different energy sources are now available to target the cancer lesion within the prostate with less significant side-effects on urinary and sexual function compared to radical treatment. Evidence shows that men value these functions highly and would even trade years of life in exchange for preserved retention of continence or erectile function. Focal treatment of prostate cancer aims to provide both cancer control and preservation of sexual and urinary functions so that men do not have to make a choice between the two. This is a treatment option that men clearly want and deserve.

Mode and Frame Matter: Assessing the Impact of Survey Mode and Sample Frame in Choice Experiments

Background. Choice experiments (CE) are applied in health economics to elicit public preferences and willingness to pay (WTP). CEs are frequently administered as Internet-based surveys. Internet surveys have recognized advantages, but concerns exist about the representativeness of Internet samples, data quality, and the impact on elicited values. Aim. We conducted the first study in health comparing an Internet-based CE survey with the more traditional general population mail survey. We also compared the Internet-based and mail CE surveys with computer-assisted personal interviews (CAPIs), which are commonly used to elicit health state valuations. Methods. Two separate samples were drawn from 2 United Kingdom (UK) volunteer Internet panels (IPs), CAPIs were undertaken with respondents sampled from UK Census Output Areas, and mail surveys were sent to UK households drawn from the postcode address file (PAF). Each mode received more than 1000 respondents. We compared modes and frames using objective measures (response rate, sample representativeness of the UK population, elicited values, theoretical validity, and cost per response) and subjective/self-reported measures (time taken to complete the study, perceived study consequentiality, and stated attribute nonattendance). This study intentionally confounded the survey modes and sample frame by choosing sample frames that are typically used by researchers for each mode. Results. Estimated WTP differs across mode-frame pairs. On most measures, CAPIs dominated. They are more expensive, however. On all measures, except response rates, Internet surveys dominated the mail survey. They were also cheaper. Conclusion. Researchers using IPs should pay attention to response rates and be aware that the quality of IPs differs. Given the importance of perceived consequentiality and attribute attendance in CEs, future research should address their impact across modes and frames.

Designing Unforced Choice Experiments to Inform Health Care Decision Making: Implications of Using Opt-Out, Neither, or Status Quo Alternatives in Discrete Choice Experiments

Background. Discrete choice experiments (DCEs) are increasingly used in the health care context to inform on patient preferences for health care services. In order for such experiments to provide useful and policy-relevant information, it is vital that the design includes those options that the respondent faces in the real-life situation. Whether to include opt-out, neither, or status quo alternatives has, however, received little attention in the DCE literature. We aim to investigate whether the use of different unforced choice formats affects DCE results in different settings: 1) opt-out versus neither in a health care market where there is no status quo and 2) including status quo in addition to opt-out in a health care market with a status quo. Design. A DCE on Dutch citizens’ preferences for personal health records served as our case, and 3189 respondents were allocated to the different unforced choice formats. We used mixed logit error component models to estimate preferences. Results. We found that the use of different unforced choice formats affects marginal utilities and welfare estimates and hence the conclusions that will be drawn from the DCE to inform health care decision making. Conclusions. To avoid biased estimates, we recommend that researchers are hesitant to use the neither option and consider including a status quo in addition to opt-out in settings where a status quo exists.

Farmers' preferences for high-input agriculture supported by site-specific extension services: Evidence from a choice experiment in Nigeria

Agricultural extension to improve yields of staple food crops and close the yield gap in Sub-Saharan Africa often entails general recommendations on soil fertility management that are distributed to farmers in a large growing area. Site-specific extension recommendations that are better tailored to the needs of individual farmers and fields, and enabled by digital technologies, could potentially bring about yield and productivity improvements. In this paper, we analyze farmers' preferences for high-input maize production supported by site-specific nutrient management recommendations provided by an ICT-based extension tool that is being developed for extension services in the maize belt of Nigeria. We use a choice experiment to provide ex-ante insights on the adoption potentials of site-specific extension services from the perspective of farmers. We control for attribute non-attendance and account for class as well as scale heterogeneity in preferences using different models, and find robust results. We find that farmers have strong preferences to switch from general to ICT-enabled site-specific soil fertility management recommendations which lend credence to the inclusion of digital technologies in agricultural extension. We find heterogeneity in preferences that is correlated with farmers' resource endowments and access to services. A first group of farmers are strong potential adopters; they are better-off, less sensitive to risk, and are more willing to invest in a high-input maize production system. A second group of farmers are weak potential adopters; they have lower incomes and fewer productive assets, are more sensitive to yield variability, and prefer less capital and labor intensive production techniques. Our empirical findings imply that improving the design of extension tools to enable provision of information on the riskiness of expected outcomes and flexibility in switching between low-risk and high-risk recommendations will help farmers to make better informed decisions, and thereby improve the uptake of extension advice and the efficiency of extension programs.

Women's Preferences for Maternal Healthcare Services in Bangladesh: Evidence from a Discrete Choice Experiment

Despite substantial improvements in several maternal health indicators, childbearing and birthing remain a dangerous experience for many women in Bangladesh. This study assessed the relative importance of maternal healthcare service characteristics to Bangladeshi women when choosing a health facility to deliver their babies. The study used a mixed-methods approach. Qualitative methods (expert interviews, focus group discussions) were initially employed to identify and develop the characteristics which most influence a women's decision making when selecting a maternal health service facility. A discrete choice experiment (DCE) was then constructed to elicit women's preferences. Women were shown choice scenarios representing hypothetical health facilities with nine attributes outlined. The women were then asked to rank the attributes they considered most important in the delivery of their future babies. A Hierarchical Bayes method was used to measure mean utility parameters. A total of 601 women completed the DCE survey. The model demonstrated significant predictive strength for actual facility choice for maternal health services. The most important attributes were the following: consistent access to a female doctor, the availability of branded drugs, respectful provider attitudes, a continuum of maternal healthcare including the availability of a C-section delivery and lesser waiting times. Attended maternal healthcare utilisation rates are low despite the access to primary healthcare facilities. Further implementation of quality improvements in maternal healthcare facilities should be prioritised.

Big Data: Will It Improve Patient-Centered Care?

Within a generation, empirical researchers have experienced unprecedented increases in the availability of data. 'Big data' has arrived with considerable hype and a sense that these are dramatic shifts in the research environment that have wide-reaching implications across many disciplines. There is no doubt that the analysis of new and varied sources of data currently available to researchers in health have the potential to better measure, monitor and describe health outcomes of patients and to uncover interesting patterns in how patients respond to treatments and interact with the health system. What is less clear is whether answers are readily available to more nuanced and substantive research questions. Here, the data-rich environment needs to be complemented by considerable research effort developing novel research designs and generating new and improved methods of analysis. Importantly, this will require researchers to be able to combine data from multiple sources and to be pro-active in data collection.

Discrete Choice Experiments: A Guide to Model Specification, Estimation and Software

We provide a user guide on the analysis of data (including best-worst and best-best data) generated from discrete-choice experiments (DCEs), comprising a theoretical review of the main choice models followed by practical advice on estimation and post-estimation. We also provide a review of standard software. In providing this guide, we endeavour to not only provide guidance on choice modelling but to do so in a way that provides a 'way in' for researchers to the practicalities of data analysis. We argue that choice of modelling approach depends on the research questions, study design and constraints in terms of quality/quantity of data and that decisions made in relation to analysis of choice data are often interdependent rather than sequential. Given the core theory and estimation of choice models is common across settings, we expect the theoretical and practical content of this paper to be useful to researchers not only within but also beyond health economics.

Testing the External Validity of a Discrete Choice Experiment Method: An Application to Latent Tuberculosis Infection Treatment

OBJECTIVES

To explore the external validity and predictive power of stated preferences obtained from a discrete choice experiment (DCE) by comparing the predicted behavior of respondents to their actual choices at an individual level.

METHODS

A DCE was performed in patients before being offered treatment for latent tuberculosis infection. A mixed logit model was estimated using hierarchical Bayes. The individual-specific preference coefficients were used to calculate the expected probability of choosing the treatment by each patient. The predicted choice using this probability was compared with their actual decision. We used a receiver-operating characteristic curve and different thresholds to convert probabilities into the predicted choices. The comparability of different distributions for the random parameters was also examined.

RESULTS

Our results identified significant heterogeneity in preferences for all attributes among respondents. The best model correctly predicted actual treatment decisions for 83% of the participants. The results from using different thresholds and a receiver-operating characteristic curve also confirmed the compatibility between predicted and actual choices. We showed that individual-specific coefficients reflected respondents' actual choices more closely compared with the aggregate-level estimates.

CONCLUSIONS

The results of this study provided support for the external validity of DCEs on the basis of their power to predict actual behavior in this setting. Future investigations are, however, required to establish the external validity of DCEs in different settings.

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.

Factors that influence variation in clinical decision-making about thrombolysis in the treatment of acute ischaemic stroke: results of a discrete choice experiment

Background

Intravenous thrombolysis for patients with acute ischaemic stroke is underused (only 80% of eligible patients receive it) and there is variation in its use across the UK. Previously, variation might have been explained by structural differences; however, continuing variation may reflect differences in clinical decision-making regarding the eligibility of patients for treatment. This variation in decision-making could lead to the underuse, or result in inappropriate use, of thrombolysis.

Objectives

To identify the factors which contribute to variation in, and influence, clinicians’ decision-making about treating ischaemic stroke patients with intravenous thrombolysis.

Methods

A discrete choice experiment (DCE) using hypothetical patient vignettes framed around areas of clinical uncertainty was conducted to better understand the influence of patient-related and clinician-related factors on clinical decision-making. An online DCE was developed following an iterative five-stage design process. UK-based clinicians involved in final decision-making about thrombolysis were invited to take part via national professional bodies of relevant medical specialties. Mixed-logit regression analyses were conducted.

Results

A total of 138 clinicians responded and opted to offer thrombolysis in 31.4% of cases. Seven patient factors were individually predictive of the increased likelihood of offering thrombolysis (compared with reference levels in brackets): stroke onset time of 2 hours 30 minutes (50 minutes); pre-stroke dependency modified Rankin Scale score (mRS) of 3 (mRS4); systolic blood pressure (SBP) of 185 mmHg (140 mmHg); stroke severity scores of National Institutes of Health Stroke Scale (NIHSS) 5 without aphasia, NIHSS 14 and NIHSS 23 (NIHSS 2 without aphasia); age 85 years (65 years); and Afro-Caribbean (white). Factors predictive of not offering thrombolysis were age 95 years; stroke onset time of 4 hours 15 minutes; severe dementia (no memory problems); and SBP of 200 mmHg. Three clinician-related factors were predictive of an increased likelihood of offering thrombolysis (perceived robustness of the evidence for thrombolysis; thrombolysing more patients in the past 12 months; and high discomfort with uncertainty) and one factor was predictive of a decreased likelihood of offering treatment (clinicians’ being comfortable treating patients outside the licensing criteria).

Limitations

We anticipated a sample size of 150–200. Nonetheless, the final sample of 138 is good considering that the total population of eligible UK clinicians is relatively small. Furthermore, data from the Royal College of Physicians suggest that our sample is representative of clinicians involved in decision-making about thrombolysis.

Conclusions

There was considerable heterogeneity among respondents in thrombolysis decision-making, indicating that clinicians differ in their thresholds for treatment across a number of patient-related factors. Respondents were significantly more likely to treat 85-year-old patients than patients aged 68 years and this probably reflects acceptance of data from Third International Stroke Trial that report benefit for patients aged > 80 years. That respondents were more likely to offer thrombolysis to patients with severe stroke than to patients with mild stroke may indicate uncertainty/concern about the risk/benefit balance in treatment of minor stroke. Findings will be disseminated via peer-review publication and presentation at national/international conferences, and will be linked to training/continuing professional development (CPD) programmes.

Future work

The nature of DCE design means that only a subset of potentially influential factors could be explored. Factors not explored in this study warrant future research. Training/CPD should address the impact of non-medical influences on decision-making using evidence-based strategies.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

The use of specialty training to retain doctors in Malawi: A discrete choice experiment

Emigration has contributed to a shortage of doctors in many sub-Saharan African countries. Specialty training is highly valued by doctors and a potential tool for retention. Yet not all types of training may be valued equally. In the first study to examine preferences for postgraduate training in depth, we carried out a discrete choice experiment as part of a cross-sectional survey of all Malawian doctors within seven years of graduation and not yet in specialty training. Over August 2012 to March 2013, 148 doctors took part out of 153 eligible in Malawi. Despite evidence that specialty training is highly sought after, Malawian junior doctors would not accept all types of training. Doctors preferred timely training outside of Malawi in core specialties (internal medicine, general surgery, paediatrics, obstetrics & gynaecology). Specialty preferences are particularly strong, with most junior doctors requiring nearly double their monthly salary to accept training all in Malawi and over six-fold to accept training in ophthalmology (representing a bundle of unpopular but priority specialties). In contrast, the location of work before training did not significantly influence most doctors' choices when guaranteed specialty training. Using a latent class model, we identified four subgroups of junior doctors with distinct preferences. Policy simulations showed that these preferences could be leveraged by policymakers to improve retention in exchange for guaranteed specialty training, however incentivising the uptake of training in priority specialties will only be effective in those with more flexible preferences. These results indicate that indiscriminate expansion of postgraduate training to slow emigration of doctors from sub-Saharan African countries may not be effective unless doctors' preferences are taken into account.

Measuring High-Risk Patients' Preferences for Pharmacogenetic Testing to Reduce Severe Adverse Drug Reaction: A Discrete Choice Experiment

OBJECTIVES

To investigate patient preferences and willingness to pay (WTP) for a genetic test that can reduce the risk of life-threatening adverse drug reactions (ADRs). We hypothesize that test features (risk of developing the adverse reaction with and without testing, test cost, and treatment cost) and the choice context (physician recommendation and the most common choice made by peer patients) will influence choices.

METHODS

A discrete choice experiment was conducted in which 189 patients at high risk for gout were asked to choose between treatment options that varied along key attributes. A latent class logit model was used to analyze the choice data and test the hypotheses.

RESULTS

We identified two classes of patients: the risk-averse class and the cost-conscious class. The WTP to reduce the risk of life-threatening ADRs from 1 out of 600 to 1 out of 1 million was SGD1215 in the risk-averse class. In contrast, in the cost-conscious class, the WTP was insensitive to the extent of risk reduction. Overall, the predicted take-up rate for the test is 65% at a price of SGD400. If the test was recommended by a physician or was chosen by most of the patients, the take-up rate for the test would increase by 8.5 and 1.5 percentage points, respectively.

CONCLUSIONS

There is a potentially large demand for genetic tests that could reduce the risk of life-threatening ADRs. Physician recommendations and providing information on the choices of others are powerful influences on demand, even more so than moderate price reductions.

Effectiveness and acceptability of parental financial incentives and quasi-mandatory schemes for increasing uptake of vaccinations in preschool children: systematic review, qualitative study and discrete choice experiment

BACKGROUND

Uptake of preschool vaccinations is less than optimal. Financial incentives and quasi-mandatory policies (restricting access to child care or educational settings to fully vaccinated children) have been used to increase uptake internationally, but not in the UK.

OBJECTIVE

To provide evidence on the effectiveness, acceptability and economic costs and consequences of parental financial incentives and quasi-mandatory schemes for increasing the uptake of preschool vaccinations.

DESIGN

Systematic review, qualitative study and discrete choice experiment (DCE) with questionnaire.

SETTING

Community, health and education settings in England.

PARTICIPANTS

Qualitative study - parents and carers of preschool children, health and educational professionals. DCE - parents and carers of preschool children identified as 'at high risk' and 'not at high risk' of incompletely vaccinating their children.

DATA SOURCES

Qualitative study - focus groups and individual interviews. DCE - online questionnaire.

REVIEW METHODS

The review included studies exploring the effectiveness, acceptability or economic costs and consequences of interventions that offered contingent rewards or penalties with real material value for preschool vaccinations, or quasi-mandatory schemes that restricted access to 'universal' services, compared with usual care or no intervention. Electronic database, reference and citation searches were conducted.

RESULTS

Systematic review - there was insufficient evidence to conclude that the interventions considered are effective. There was some evidence that the quasi-mandatory interventions were acceptable. There was insufficient evidence to draw conclusions on economic costs and consequences. Qualitative study - there was little appetite for parental financial incentives. Quasi-mandatory schemes were more acceptable. Optimising current services was consistently preferred to the interventions proposed. DCE and questionnaire - universal parental financial incentives were preferred to quasi-mandatory interventions, which were preferred to targeted incentives. Those reporting that they would need an incentive to vaccinate their children completely required around £110. Those who did not felt that the maximum acceptable incentive was around £70.

LIMITATIONS

Systematic review - a number of relevant studies were excluded as they did not meet the study design inclusion criteria. Qualitative study - few partially and non-vaccinating parents were recruited. DCE and questionnaire - data were from a convenience sample.

CONCLUSIONS

There is little current evidence on the effectiveness or economic costs and consequences of parental financial incentives and quasi-mandatory interventions for preschool vaccinations. Universal incentives are likely to be more acceptable than targeted ones. Preferences concerning incentives versus quasi-mandatory interventions may depend on the context in which these are elicited.

FUTURE WORK

Further evidence is required on (i) the effectiveness and optimal configuration of parental financial incentive and quasi-mandatory interventions for preschool vaccinations - if effectiveness is confirmed, further evidence is required on how to communicate this to stakeholders and the impact on acceptability; and (ii) the acceptability of parental financial incentive and quasi-mandatory interventions for preschool vaccinations to members of the population who are not parents of preschool children or relevant health professionals. Further consideration should be given to (i) incorporating reasons for non-vaccination into new interventions for promoting vaccination uptake; and (ii) how existing services can be optimised.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42012003192.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Understanding Patient Preferences in Medication Nonadherence: A Review of Stated Preference Data

Nonadherence is a global problem undermining the cost-effectiveness of evidence-based medications. Aligning treatment choices with patient preferences may promote adherent behaviour: eliciting patient treatment preferences may help resolve the problem of nonadherence. As there is no reliable measure of nonadherent behaviour that can be used to derive preferences, stated-preference techniques offer a robust alternative. To understand patient preferences in medication nonadherence, we systematically appraised full-text English studies (from database inception to 24 February 2014) involving participants evaluating hypothetical scenarios to elicit preferences as an explicit means to understand medication nonadherence. Study characteristics (e.g. setting, disease, stated-preference method), attribute type and influence on choice were extracted. Seventeen full-text articles (4,456 patients) were included in the review, which reports stated-preference elicitation studies across a wide range of chronic and acute conditions. All studies were conducted in high-income settings. The influence of drug-related factors was predominant in patients' preferences for treatment. Patients preferred efficacious over safe medications except when considering the duration of therapy, but dosing and cost appeared more important when contemplating adherence. Patient characteristics, particularly medication experience, significantly influenced preferences. A disparity between stated preferences for treatment and adherence was reported. When using stated-preference techniques to understand nonadherence, this manuscript highlights that there is much room for methodological development. Studies outside of high-income settings are needed, particularly in relation to chronic diseases, for which nonadherence poses a substantial economic burden to health systems and patients. To inform the problem of sustaining adherence, prospective research is needed to understand how preferences change with time. The usefulness of stated-preference techniques to inform policy and practice requires a better understanding of how stated preferences relate to actual adherence behaviour.

A survey of patient preferences for oral antihyperglycemic therapy in patients with type 2 diabetes mellitus

INTRODUCTION

Previous research has demonstrated a correlation among patient preferences, dosing burden, and medication nonadherence, a well-recognized challenge in type 2 diabetes mellitus (T2DM). The objective of this study was to elicit preferences for alternative dosing regimens for oral antihyperglycemic therapies among patients with T2DM and to quantify differences in dosing preferences among patients with different characteristics.

METHODS

Preferences for dosing of oral antihyperglycemic drugs (OAD) were evaluated by surveying patients with T2DM in the United States (US). Survey participants were adult US patients with T2DM who were taking no or only 1 OAD and no injectable therapies. Each patient completed a web-enabled discrete-choice experiment (DCE) including a series of 8 pairs of hypothetical OAD profiles. Each profile was defined by reductions in average glucose, dosing schedule (e.g., once-weekly, once-daily, or twice-daily dosing), chance of mild-to-moderate gastrointestinal side effects, frequency of hypoglycemia, weight change, incremental risk of congestive heart failure, and cost. Each participant also answered a direct question about dosing preference. Random-parameters logit was used to analyze the DCE data. Prespecified subgroups were analyzed.

RESULTS

Of 2,262 patients invited to participate, 923 were included in the analysis (mean age 63 years, 45% male, 79% white). Reducing dosing frequency was statistically significantly important to patients; however, it was relatively less important than medication cost or clinical outcomes. On average, patients preferred once-weekly to once-daily dosing. Patients not currently taking an OAD had a stronger preference for once-weekly dosing than patients on treatment (P = 0.012). Patients younger than 45 years had a stronger preference for weekly dosing than older patients (P < 0.075).

CONCLUSIONS

For younger patients and patients not currently on treatment, once-weekly dosing may provide additional incentive to initiate and adhere to antihyperglycemic treatment; however, additional research will be required to confirm this hypothesis.

Reconceptualising the external validity of discrete choice experiments

External validity is a crucial but under-researched topic when considering using discrete choice experiment (DCE) results to inform decision making in clinical, commercial or policy contexts. We present the theory and tests traditionally used to explore external validity that focus on a comparison of final outcomes and review how this traditional definition has been empirically tested in health economics and other sectors (such as transport, environment and marketing) in which DCE methods are applied. While an important component, we argue that the investigation of external validity should be much broader than a comparison of final outcomes. In doing so, we introduce a new and more comprehensive conceptualisation of external validity, closely linked to process validity, that moves us from the simple characterisation of a model as being or not being externally valid on the basis of predictive performance, to the concept that external validity should be an objective pursued from the initial conceptualisation and design of any DCE. We discuss how such a broader definition of external validity can be fruitfully used and suggest innovative ways in which it can be explored in practice.

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.

Understanding clinicians' decisions to offer intravenous thrombolytic treatment to patients with acute ischaemic stroke: a protocol for a discrete choice experiment

BACKGROUND

Intravenous thrombolysis is an effective emergency treatment for acute ischaemic stroke for patients meeting specific criteria. Approximately 12% of eligible patients in England, Wales and Northern Ireland received thrombolysis in the first quarter of 2013, yet as many as 15% are eligible to receive treatment. Suboptimal use of thrombolysis may have been largely attributable to structural factors; however, with the widespread implementation of 24/7 hyper acute stroke services, continuing variation is likely to reflect differences in clinical decision-making, in particular the influence of ambiguous areas within the guidelines, licensing criteria and research evidence. Clinicians' perceptions about thrombolysis may now exert a greater influence on treatment rates than structural/service factors. This research seeks to elucidate factors influencing thrombolysis decision-making by using patient vignettes to identify (1) patient-related and clinician-related factors that may help to explain variation in treatment and (2) associated trade-offs in decision-making based on the interplay of critical factors.

METHODS/ANALYSIS

A discrete choice experiment (DCE) will be conducted to better understand how clinicians make decisions about whether or not to offer thrombolysis to patients with acute ischaemic stroke. To inform the design, exploratory work will be undertaken to ensure that (1) all potentially influential factors are considered for inclusion; and (2) to gain insights into the 'grey areas' of patient factors. A fractional factorial design will be used to combine levels of patient factors in vignettes, which will be presented to clinicians to allow estimation of the variable effects on decisions to offer thrombolysis.

ETHICS AND DISSEMINATION

Ethical approval for this study was obtained from the Newcastle University Research Ethics Committee. The results will be disseminated in peer review publications and at national conferences. Findings will be translated into continuing professional development activities and will support implementation of a computerised decision aid for thrombolysis (COMPASS) in acute stroke care.

Stated preferences for anti-malarial drug characteristics in Zomba, a malaria endemic area of Malawi

Background

The evidence on determinants of individuals’ choices for anti-malarial drug treatments is scarce. This study sought to measure the strength of preference for adult antimalarial drug treatment attributes of heads of urban, rural and peri-urban households in a resource-limited malaria-endemic area of sub-Saharan Africa.

Methods

Discrete choice experiments were conducted with 508 heads of household interviewed face-to-face for a household population survey of health-seeking behavior in Zomba District, Malawi. The interviews were held in Chichewa and the choice experiment questions were presented with cartoon aids. The anti-malarial drug attributes included in the stated preference experiment were: speed of fever resolution, side effects (pruritus) risk, protection (duration of prophylactic effect), price, duration of treatment course and recommendation by a health professional. Sixteen treatment profiles from a fractional factorial design by orthogonal array were paired into choice scenarios, and scenarios were randomly assigned to participants so that each participant was presented with a series of eight pairwise choice scenarios. Respondents had the option to state indifference between the two profiles or decline to choose. Data were analysed in a mixed logit model, with normally distributed coefficients for all six attributes.

Results

The sex ratio was balanced in urban areas, whereas 63% of participants in rural areas were male. The proportion of individuals with no education was considerably higher in the rural group (25%) than in the urban (5%) and peri-urban (6%) groups. All attributes investigated had the expected influence, and traded-off in most respondents’ choices. There were heterogeneous effects of price, pruritus risk, treatment recommendation by a professional, and duration of prophylaxis across respondents, only partly explained by their differences in education, household per capita expenditure, sex and age. Individuals´ demand elasticity (simulated median, inter-quartile range) was highest (most responsive) to speed of symptom resolution (0.88, 0.80-0.89) and pruritus risk (0.25, 0.08-0.62).

Conclusions

Most adult antimalarial users are willing to use treatments without recommendation from health professional, and may be influenced by price. Future studies should investigate the magnitude of differences in price and treatment attribute sensitivity between adult anti-malarial drug users in rural, peri-urban and urban areas in order to determine optimal price subsidies.

An Australian discrete choice experiment to value eq-5d health states

Conventionally, generic quality-of-life health states, defined within multi-attribute utility instruments, have been valued using a Standard Gamble or a Time Trade-Off. Both are grounded in expected utility theory but impose strong assumptions about the form of the utility function. Preference elicitation tasks for both are complicated, limiting the number of health states that each respondent can value and, therefore, that can be valued overall. The usual approach has been to value a set of the possible health states and impute values for the remainder. Discrete Choice Experiments (DCEs) offer an attractive alternative, allowing investigation of more flexible specifications of the utility function and greater coverage of the response surface. We designed a DCE to obtain values for EQ-5D health states and implemented it in an Australia-representative online panel (n = 1,031). A range of specifications investigating non-linear preferences with respect to time and interactions between EQ-5D levels were estimated using a random-effects probit model. The results provide empirical support for a flexible utility function, including at least some two-factor interactions. We then constructed a preference index such that full health and death were valued at 1 and 0, respectively, to provide a DCE-based algorithm for Australian cost-utility analyses.

Physician and patient willingness to pay for electronic cardiovascular disease management

OBJECTIVES

Cardiovascular disease (CVD) is an important target for electronic decision support. We examined the potential sustainability of an electronic CVD management program using a discrete choice experiment (DCE). Our objective was to estimate physician and patient willingness-to-pay (WTP) for the current and enhanced programs.

METHODS

Focus groups, expert input and literature searches decided the attributes to be evaluated for the physician and patient DCEs, which were carried out using a Web-based program. Hierarchical Bayes analysis estimated preference coefficients for each respondent and latent class analysis segmented each sample. Simulations were used to estimate WTP for each of the attributes individually and for an enhanced vascular management system.

RESULTS

144 participants (70 physicians, 74 patients) completed the DCE. Overall, access speed to updated records and monthly payments for a nurse coordinator were the main determinants of physician choices. Two distinctly different segments of physicians were identified - one very sensitive to monthly subscription fee and speed of updating the tracker with new patient data and the other very sensitive to the monthly cost of the nurse coordinator and government billing incentives. Patient choices were most significantly influenced by the yearly subscription cost. The estimated physician WTP was slightly above the estimated threshold for sustainability while the patient WTP was below.

CONCLUSION

Current willingness to pay for electronic cardiovascular disease management should encourage innovation to provide economies of scale in program development, delivery and maintenance to meet sustainability thresholds.

Quantifying preferences for asthma control in parents and adolescents using best-worst scaling

BACKGROUND

Understanding the views of parents and children is critical to designing effective asthma management programs. It was hypothesized that parents and adolescents would exhibit heterogenous preferences with regard to asthma control.

METHODS

Fifty parents of children with asthma and 51 adolescents with asthma participated in a best-worst scaling study to quantify preferences regarding night-time symptoms, wheezing/chest tightening, changes in asthma medications, emergency visits and physical activity limitations.

RESULTS

A latent class analysis revealed heterogeneity inherent in the preferences of parents and adolescents. Two classes of parents emerged from the analysis that displayed significantly different preferences. The first displayed strong preferences for averting night-time symptoms, wheezing/chest tightening, physical activity limitations and emergency room visits with odds ratios (OR) of 42 (95% CI 24, 72), 40 (95% CI 23, 68), 26 (95% CI 15, 44) and 21 (95% CI 12, 35), respectively, compared to an OR of 1 for 10 physical activity limitations per month. A second smaller parent class displayed more balanced preferences. Most adolescents displayed similar preferences for averting night-time symptoms, wheezing/chest tightening, physical activity limitations and emergency room visits, with ORs of 28 (95% CI 16, 48), 25 (95% CI 14, 44), 27 (95% CI 15, 46) and 20 (95% CI 11, 34) respectively.

CONCLUSIONS

This study revealed the importance placed on averting night-time symptoms, wheezing and chest tightening, emergency room visits and physical activity limitations by parents and adolescents alike, with greater emphasis on symptom aversion by parents. Preference heterogeneity exists and should be considered in customized asthma management programs.

An exploration of parents' preferences for foot care in juvenile idiopathic arthritis: a possible role for the discrete choice experiment

Background

An increased awareness of patients’ and parents’ care preferences regarding foot care is desirable from a clinical perspective as such information may be utilised to optimise care delivery. The aim of this study was to examine parents’ preferences for, and valuations of foot care and foot-related outcomes in juvenile idiopathic arthritis (JIA).

Methods

A discrete choice experiment (DCE) incorporating willingness-to-pay (WTP) questions was conducted by surveying 42 parents of children with JIA who were enrolled in a randomised-controlled trial of multidisciplinary foot care at a single UK paediatric rheumatology outpatients department. Attributes explored were: levels of pain; mobility; ability to perform activities of daily living (ADL); waiting time; referral route; and footwear. The DCE was administered at trial baseline. DCE data were analysed using a multinomial-logit-regression model to estimate preferences and relative importance of attributes of foot care. A stated-preference WTP question was presented to estimate parents’ monetary valuation of health and service improvements.

Results

Every attribute in the DCE was statistically significant (p < 0.01) except that of cost (p = 0.118), suggesting that all attributes, except cost, have an impact on parents’ preferences for foot care for their child. The magnitudes of the coefficients indicate that the strength of preference for each attribute was (in descending order): improved ability to perform ADL, reductions in foot pain, improved mobility, improved ability to wear desired footwear, multidisciplinary foot care route, and reduced waiting time. Parents’ estimated mean annual WTP for a multidisciplinary foot care service was £1,119.05.

Conclusions

In terms of foot care service provision for children with JIA, parents appear to prefer improvements in health outcomes over non-health outcomes and service process attributes. Cost was relatively less important than other attributes suggesting that it does not appear to impact on parents’ preferences.

Eliciting preferences to inform patient-centred policies: the case of psoriasis

OBJECTIVE

To assess patient preferences for psoriasis treatment features and to investigate the heterogeneity of preferences among patients with different socio-demographic and disease-related characteristics.

METHODOLOGY

A discrete choice experiment was conducted on adult patients with moderate to severe plaque-type psoriasis during a routine visit to their physician at 15 centres in Italy. We investigated the preferences of patients with respect to five treatment attributes: (1) mode and frequency of administration; (2) time to improvement; (3) time free of symptoms; (4) unintended life expectancy reduction resulting from treatment; and (5) monthly treatment cost. The heterogeneity of preferences was investigated in a mixed logit model with normally distributed random coefficients.

RESULTS

Overall, patients preferred the subcutaneous or intravenous route of administration (versus oral administration) and treatments that took less time to show improvement, ensured a longer time free of symptoms, involved a lesser reduction in life expectancy and had lower costs. There was significant preference heterogeneity for all attributes. The cost attribute was found to be significantly more important to females and to older patients (above 60 years of age). Older patients placed significantly greater emphasis on reduced life expectancy, whereas the time free of symptoms was significantly less important to them than to patients under 60 years of age. Patients with higher scores on the Dermatology Life Quality Index (DLQI) placed higher value on the time free of symptoms than those with lower DLQI scores. For the overall sample, the marginal willingness to pay (WTP) for a month's reduction in the time to improvement was <euro>32.4, whereas the WTP for one additional month without symptoms was significantly higher (<euro>68.2).

CONCLUSION

Patient-centred policies should consider the heterogeneity of patients' expectations to identify individualized treatments that would aid in optimizing patient satisfaction and wellbeing, as well as overall treatment effectiveness.

Valuing SF-6D Health States Using a Discrete Choice Experiment

BACKGROUND

SF-6D utility weights are conventionally produced using a standard gamble (SG). SG-derived weights consistently demonstrate a floor effect not observed with other elicitation techniques. Recent advances in discrete choice methods have allowed estimation of utility weights. The objective was to produce Australian utility weights for the SF-6D and to explore the application of discrete choice experiment (DCE) methods in this context. We hypothesized that weights derived using this method would reflect the largely monotonic construction of the SF-6D.

METHODS

We designed an online DCE and administered it to an Australia-representative online panel (n = 1017). A range of specifications investigating nonlinear preferences with respect to additional life expectancy were estimated using a random-effects probit model. The preferred model was then used to estimate a preference index such that full health and death were valued at 1 and 0, respectively, to provide an algorithm for Australian cost-utility analyses.

RESULTS

Physical functioning, pain, mental health, and vitality were the largest drivers of utility weights. Combining levels to remove illogical orderings did not lead to a poorer model fit. Relative to international SG-derived weights, the range of utility weights was larger with 5% of health states valued below zero.

CONCLUSION

s. DCEs can be used to investigate preferences for health profiles and to estimate utility weights for multi-attribute utility instruments. Australian cost-utility analyses can now use domestic SF-6D weights. The comparability of DCE results to those using other elicitation methods for estimating utility weights for quality-adjusted life-year calculations should be further investigated.

Patient preferences for biologic agents in rheumatoid arthritis: a discrete-choice experiment

OBJECTIVES

To assess patients' preferences for rheumatoid-arthritis treatments with biologic agents using a discrete-choice experiment.

METHODS

A discrete-choice experiment was conducted with adult rheumatoid-arthritis patients who had never been treated with biological agents from two university hospitals-public and private-in Buenos Aires, Argentina. We evaluated preferences for seven treatment attributes (with two to three levels each): effectiveness, mode of administration, frequency of administration, local and systemic adverse events, severe infections, and out-of-pocket costs.A probit regression model was used to analyze the relative importance of rheumatoid-arthritis treatment attributes. We estimated attributes' relative importance and their 95% confidence intervals.

RESULTS

Survey responses from 240 patients with rheumatoid arthritis receiving conventional disease-modifying antirheumatic drugs were included in the study. All tested biological agents' attributes significantly affected the choice of treatment. Attributes' relative importance in decreasing order was the following (mean, confidence interval 95%): cost, 0.81 (0.69-0.92); systemic adverse events, 0.66 (0.57-0.76); frequency of administration, 0.61 (0.52-0.71); efficacy, 0.42 (0.32-0.51); route of administration, 0.41 (0.30-0.52); local adverse events, 0.40 (0.31-0.49); and serious infections, 0.29 (0.22-0.37).

CONCLUSIONS

Different treatment attributes had a significant and different influence in rheumatoid-arthritis patients' choice of biological agents. This type of study can not only inform about patients' preferences but also about the trade-offs among different possible treatments or process-related attributes.

Consumer preferences for health and nonhealth outcomes of health promotion: results from a discrete choice experiment

OBJECTIVE

Health promotion (HP) interventions have outcomes that go beyond health. Such broader nonhealth outcomes are usually neglected in economic evaluation studies. To allow for their consideration, insights are needed into the types of nonhealth outcomes that HP interventions produce and their relative importance compared with health outcomes. This study explored consumer preferences for health and nonhealth outcomes of HP in the context of lifestyle behavior change.

METHODS

A discrete choice experiment was conducted among participants in a lifestyle intervention (n = 132) and controls (n = 141). Respondents made 16 binary choices between situations that can be experienced after lifestyle behavior change. The situations were described by 10 attributes: future health state value, start point of future health state, life expectancy, clothing size above ideal, days with sufficient relaxation, endurance, experienced control over lifestyle choices, lifestyle improvement of partner and/or children, monetary cost per month, and time cost per week.

RESULTS

With the exception of "time cost per week" and "start point of future health state," all attributes significantly determined consumer choices. Thus, both health and nonhealth outcomes affected consumer choice. Marginal rates of substitution between the price attribute and the other attributes revealed that the attributes "endurance," "days with sufficient relaxation," and "future health state value" had the greatest impact on consumer choices. The "life expectancy" attribute had a relatively low impact and for increases of less than 3 years, respondents were not willing to trade.

CONCLUSIONS

Health outcomes and nonhealth outcomes of lifestyle behavior change were both important to consumers in this study. Decision makers should respond to consumer preferences and consider nonhealth outcomes when deciding about HP interventions.

Contingent valuation scenarios for chronic illnesses: the case of childhood asthma

OBJECTIVES

We use a contingent valuation (CV) study of childhood asthma to discuss a central issue in designing CV studies of chronic illness-the need for a detailed, realistic scenario that minimizes confounding factors-and show how to address this issue. We apply our methodology to estimate households' willingness to pay (WTP) for reductions in asthma morbidity.

METHODS

By using a combination of focus groups, revealed preference surveys, and epidemiological surveys, we gathered information on health status, attitudes, and beliefs regarding asthma, risk-averting behaviors, perceptions of these behaviors, and household socioeconomic characteristics. We used this information to design a CV survey that we extensively tested for validity. In the survey, we elicited participants' WTP for a hypothetical device that would reduce symptom-days by improving asthma management; these data enabled us to estimate household WTP by using a variety of econometric models.

RESULTS

Our analysis of households with children with asthma yielded the following conclusions: the scenario should address both physical asthma symptoms and the psychosocial stress of managing a chronic illness; the survey should measure household perceptions of the burden of asthma in addition to objective measures such as symptom-days; and the scenario should not involve substantial behavioral changes or a new medication, to avoid confounding household preferences with unrelated attributes of the scenario. Our primary models estimated mean household WTP for a 50% reduction in symptom-days (and accompanying reductions in psychosocial stress) at $56.48 to $64.84 per month.

CONCLUSIONS

Our methodology can be used to inform CV studies of chronic illness. Our WTP estimates can help regulatory agencies assess a wide range of policies that affect the incidence or severity of asthma.

Junior doctors' preferences for specialty choice

A number of studies suggest that there is an over-supply of specialists and an under-supply of general practitioners in many developed countries. Previous econometric studies of specialty choice from the US suggest that although income plays a role, other non-pecuniary factors may be important. This paper presents a novel application of a choice experiment to identify the effects of expected future earnings and other attributes on specialty choice. We find the implied marginal wage estimated from our discrete choice model is close to the actual wages of senior specialists, but much higher than those of senior GPs. In a policy simulation we find that increasing GPs' earnings by $50,000, or increasing opportunities for procedural or academic work can increase the number of junior doctors choosing general practice by between 8 and 13 percentage points. The simulation implies an earnings elasticity of specialty choice of 0.95.

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.

Ordinal preference elicitation methods in health economics and health services research: using discrete choice experiments and ranking methods

INTRODUCTION

The predominant method of economic evaluation is cost-utility analysis, which uses cardinal preference elicitation methods, including the standard gamble and time trade-off. However, such approach is not suitable for understanding trade-offs between process attributes, non-health outcomes and health outcomes to evaluate current practices, develop new programmes and predict demand for services and products. Ordinal preference elicitation methods including discrete choice experiments and ranking methods are therefore commonly used in health economics and health service research.

AREAS OF AGREEMENT

Cardinal methods have been criticized on the grounds of cognitive complexity, difficulty of administration, contamination by risk and preference attitudes, and potential violation of underlying assumptions. Ordinal methods have gained popularity because of reduced cognitive burden, lower degree of abstract reasoning, reduced measurement error, ease of administration and ability to use both health and non-health outcomes.

AREAS OF CONTROVERSY

The underlying assumptions of ordinal methods may be violated when respondents use cognitive shortcuts, or cannot comprehend the ordinal task or interpret attributes and levels, or use 'irrational' choice behaviour or refuse to trade-off certain attributes. CURRENT USE AND GROWING AREAS: Ordinal methods are commonly used to evaluate preference for attributes of health services, products, practices, interventions, policies and, more recently, to estimate utility weights. AREAS FOR ON-GOING RESEARCH: There is growing research on developing optimal designs, evaluating the rationalization process, using qualitative tools for developing ordinal methods, evaluating consistency with utility theory, appropriate statistical methods for analysis, generalizability of results and comparing ordinal methods against each other and with cardinal measures.

The development of quality indicators in mental healthcare: a discrete choice experiment

BACKGROUND

Health care regulatory agencies perform audits or inspections to judge the quality and safety of health care. This judgment is based on the assessment of a large set of health care indicators as accepted by the profession. However, there is a lack of knowledge about the influence of these indicators and whether a smaller number would be sufficient for a quality assessment or audit procedure.

METHODS

A discrete choice experiment (DCE) was performed for the assessment of quality of care regarding the management of patients with schizophrenia and drug dependency in psychiatric institutes. Based on multidisciplinary guidelines for the treatment of schizophrenia and a visit of (co)inspectors of the Dutch Healthcare Inspectorate at all 33 integrated mental hospitals a set of 51 indicators were assessed in a subsequent interview. With the analysis of the results, 6 attributes were selected for the DCE as quality indicators.

RESULTS

Seventy-six percent of all health services (co)inspectors (n = 33) involved in the inspection of mental health services, participated in the experiment. Respondents considered an operational elaborate treatment plan the most important indicator for the assessment of quality of care in a psychiatric institute, followed by a general care program, treatment outcome measurement, and involvement in treatment of patients and relatives. Pharmacotherapy and governance responsibility were valued as less important indicators.

CONCLUSIONS

The results of this DCE show that there is a prioritisation in the six selected quality indicators. This might help health services (co) inspectors to enhance the efficiency and transparency of the quality of care assessment for patients with schizophrenia and/or drug dependency in psychiatric institutes.

Patients' preferences for treatment outcomes of add-on antiepileptic drugs: a conjoint analysis

To understand the relative importance of the outcomes of add-on antiepileptic drugs (AEDs) and the willingness of patients with epilepsy to accept therapeutic trade-offs between seizure control and tolerability, we administered a Web-enabled, choice-format conjoint survey to patients with a self-reported physician diagnosis of epilepsy and symptoms of partial seizures. Patients answered nine choice questions to evaluate treatment outcomes of two different hypothetical add-on AEDs. Patients were first asked to choose the better of the two medicines and then asked a follow-up question about whether or not they would add the selected AED to their current treatment regimen. Our study demonstrated that patients with epilepsy consider seizure reduction to be the top priority when ranking it against the reduction or elimination of side effects. This study aids in better understanding of patients' AED treatment preferences and may aid in management of epilepsy.

Understanding rational non-adherence to medications. A discrete choice experiment in a community sample in Australia

Background

In spite of the potential impact upon population health and expenditure, interventions promoting medication adherence have been found to be of moderate effectiveness and cost effectiveness. Understanding the relative influence of factors affecting patient medication adherence decisions and the characteristics of individuals associated with variation in adherence will lead to a better understanding of how future interventions should be designed and targeted. This study aims to explore medication-taking decisions that may underpin intentional medication non-adherence behaviour amongst a community sample and the relative importance of medication specific factors and patient background characteristics contributing to those decisions.

Methods

A discrete choice experiment conducted through a web-enabled online survey was used to estimate the relative importance of eight medication factors (immediate and long-term medication harms and benefits, cost, regimen, symptom severity, alcohol restrictions) on the preference to continue taking a medication. To reflect more closely what usually occurs in practice, non-disease specific medication and health terms were used to mimic decisions across multiple medications and conditions.161 general community participants, matching the national Australian census data (age, gender) were recruited through an online panel provider (participation rate: 10%) in 2010.

Results

Six of the eight factors (i.e. immediate and long-term medication harms and benefits, cost, and regimen) had a significant influence on medication choice. Patient background characteristics did not improve the model. Respondents with private health insurance appeared less sensitive to cost then those without private health insurance. In general, health outcomes, framed as a side-effect, were found to have a greater influence over adherence than outcomes framed as therapeutic benefits.

Conclusions

Medication-taking decisions are the subject of rational choices, influenced by the attributes of treatments and potentially amenable to intervention through education, strategic pricing and the altering of dosing characteristics. Understanding individual treatment preferences is thus an important step to improving adherence support provision in practice. Re-framing future interventions and policies to support rational and informed individual patient choices, is the way forward to realising the full potential health and economic benefits from the efficacious use of medications.

Eliciting patients' preferences for outpatient treatment of febrile neutropenia: a discrete choice experiment

BACKGROUND

Studies have demonstrated that patients at low risk for febrile neutropenia (FN) complications can be treated safely and effectively at home. Information on patient preferences for outpatient treatment of this condition will help to optimize health care delivery to these patients. The purpose of this study was to elicit non-Hodgkin lymphoma patients' preferences on attributes related to outpatient treatment of FN.

METHODS

We used a self-administered discrete choice experiment questionnaire based on the attributes of out-of-pocket costs, unpaid caregiver time required daily, and probability of return to the hospital. Ten paired scenarios in which levels of the attributes were varied were presented to study patients. For each pair, patients indicated the scenario they preferred. Adjusted odds ratios (ORs) of accepting a scenario that described outpatient care for FN were estimated.

RESULTS

Eighty-eight patients completed the questionnaire. Adjusted ORs [95 % confidence intervals] of accepting outpatient care for FN were 0.84 [0.75, 0.95] for each $10 increase in out-of-pocket cost; 0.82 [0.68, 0.99] for each 1 h increase in daily unpaid caregiver time; and 0.53 [0.50, 0.57] for each 5 % increase in probability of return to the hospital.

CONCLUSIONS

Probability of return to the hospital was the most important attribute to patients when considering home-based care for FN. Patients considered out-of-pocket costs and unpaid caregiver time to be less important than probability of return to the hospital. This study identifies factors that could be incorporated into outpatient delivery systems for FN care to ensure adequate patient uptake and satisfaction with such programs.

Willingness to pay for mosquito control: how important is West Nile virus risk compared to the nuisance of mosquitoes?

Public health programs that control mosquitoes and other disease vectors have the added benefit of reducing residents' exposure to pest insects. We surveyed homeowners in Madison, Wisconsin, and used an economic valuation method, stated-choice experiments, to measure willingness to pay (WTP) for control of West Nile virus (WNV)-transmitting and nuisance mosquitoes under current and increased levels of WNV risk. Under current WNV risk levels (approximately 1 in 250,000), the average Madison survey respondent was not willing to pay for programs that targeted West Nile-transmitting mosquitoes only (WTP=-$21, 95% [CI -$63, $20]), while WTP for a reduction in nuisance mosquitoes was substantial (WTP=$147, 95% [CI $109, $186]). As the risk of WNV was increased, WTP for control of disease-carrying mosquitoes also increased (WTP=$158; 95% CI [$111, $206] at the highest risk level), but WTP for nuisance control remained high (WTP=$108; 95% CI [$78, $138]). Among homeowners in our sample, the "nuisance factor" was more important than the "disease factor" in terms of respondents' demand for mosquito control.

Integrating evidence into policy and sustainable disability services delivery in western New South Wales, Australia: the 'wobbly hub and double spokes' project

BACKGROUND

Policy that supports rural allied health service delivery is important given the shortage of services outside of Australian metropolitan centres. The shortage of allied health professionals means that rural clinicians work long hours and have little peer or service support. Service delivery to rural and remote communities is further complicated because relatively small numbers of clients are dispersed over large geographic areas. The aim of this five-year multi-stage project is to generate evidence to confirm and develop evidence-based policies and to evaluate their implementation in procedures that allow a regional allied health workforce to more expeditiously respond to disability service need in regional New South Wales, Australia.

METHODS/DESIGN

The project consists of four inter-related stages that together constitute a full policy cycle. It uses mixed quantitative and qualitative methods, guided by key policy concerns such as: access, complexity, cost, distribution of benefits, timeliness, effectiveness, equity, policy consistency, and community and political acceptability. Stage 1 adopts a policy analysis approach in which existing relevant policies and related documentation will be collected and reviewed. Policy-makers and senior managers within the region and in central offices will be interviewed about issues that influence policy development and implementation. Stage 2 uses a mixed methods approach to collecting information from allied health professionals, clients, and carers. Focus groups and interviews will explore issues related to providing and receiving allied health services. Discrete Choice Experiments will elicit staff and client/carer preferences. Stage 3 synthesises Stage 1 and 2 findings with reference to the key policy issues to develop and implement policies and procedures to establish several innovative regional workforce and service provision projects. Stage 4 uses mixed methods to monitor and evaluate the implementation and impact of new or adapted policies that arise from the preceding stages.

DISCUSSION

The project will provide policy makers with research evidence to support consideration of the complex balance between: (i) the equitable allocation of scarce resources; (ii) the intent of current eligibility and prioritisation policies; (iii) workforce constraints (and strengths); and (iv) the most effective, evidence-based clinical practice.

Patients' value of asthma services in Australian pharmacies: the way ahead for asthma care

OBJECTIVE

Long-term sustainability of health services requires an understanding of patients' values and preferences. The aim of this study was to evaluate patients' preferences as well as their willingness-to-pay (WTP) for a community pharmacy-delivered specialized asthma service using a discrete choice experiment (DCE).

METHODS

Patients with asthma in New South Wales, Australia, who had recently experienced a specialized asthma management service at their pharmacy were mailed DCE questionnaires. Patients were asked to choose between two hypothetical service models with varying attributes. Multinomial logit models estimated patients' marginal WTP.

RESULTS

The study had a response rate of 47%. Patients greatly valued various aspects of the pharmacy-based specialized service and had marginal WTP values of AUD$18.00 for a private area, AUD$44.50 for lung function testing, AUD$9.18 for appointments with pharmacists, and AUD$22.80 for provision of comprehensive advice on asthma and its medications. The marginal WTP for the overall service was AUD$94.86.

CONCLUSIONS

The findings of the study indicate that patients greatly value and are willing to pay for asthma services in pharmacies. The study results will help pharmacists and policy advisors in the development of individualized asthma services that patients will use, are willing to pay for, and thus are economically viable in the future.

Conjoint analysis applications in health--a checklist: a report of the ISPOR Good Research Practices for Conjoint Analysis Task Force

BACKGROUND

The application of conjoint analysis (including discrete-choice experiments and other multiattribute stated-preference methods) in health has increased rapidly over the past decade. A wider acceptance of these methods is limited by an absence of consensus-based methodological standards.

OBJECTIVE

The International Society for Pharmacoeconomics and Outcomes Research (ISPOR) Good Research Practices for Conjoint Analysis Task Force was established to identify good research practices for conjoint-analysis applications in health.

METHODS

The task force met regularly to identify the important steps in a conjoint analysis, to discuss good research practices for conjoint analysis, and to develop and refine the key criteria for identifying good research practices. ISPOR members contributed to this process through an extensive consultation process. A final consensus meeting was held to revise the article using these comments, and those of a number of international reviewers.

RESULTS

Task force findings are presented as a 10-item checklist covering: 1) research question; 2) attributes and levels; 3) construction of tasks; 4) experimental design; 5) preference elicitation; 6) instrument design; 7) data-collection plan; 8) statistical analyses; 9) results and conclusions; and 10) study presentation. A primary question relating to each of the 10 items is posed, and three sub-questions examine finer issues within items.

CONCLUSIONS

Although the checklist should not be interpreted as endorsing any specific methodological approach to conjoint analysis, it can facilitate future training activities and discussions of good research practices for the application of conjoint-analysis methods in health care studies.

Deriving distributional weights for QALYs through discrete choice experiments

This paper presents the first attempt to use a discrete choice experiment to derive distributional weights for quality adjusted life years (QALYs), based on characteristics (age and severity) of the beneficiaries. A novel approach using the Hicksian compensating variation is applied. Advantages include derivation of weights for QALYs, not just for life or life years saved, and investigation of the impact of the size of the health gain by allowing the gain to be traded against other characteristics. Results suggest one would generally not weight QALYs, except in a small number of specific cases and in those cases the weights are relatively small. Methodological challenges are highlighted as is a future research agenda.