Discrete Choice Experiment (DCE) as a Tool to Elicit Patient Preferences in a Complex Benefit-Risk Evaluation: A Case Study.

The prevalence of obesity has risen substantially during the past 25 years in the United States and most developed countries, with a related increase in type 2 diabetes mellitus.1,2 Almost one third of the adult US population is considered to be obese (body mass index [BMI] ≥30), and 1 in 20 is extremely obese (BMI ≥40).3 Nearly 17% of children and adolescents are overweight in the United States.3 Obesity is associated with increased risk for type 2 diabetes mellitus, coronary heart disease (CHD), hypertension, obstructive sleep apnea, and cancer, higher overall mortality rate,4–6 and decreased longevity.7,8 Extreme obesity can truncate life expectancy in young adults by 5 to 20 years.8 Accordingly, the expected benefits of weight reduction for obese individuals are profound. Weight loss of 5% to 10% generally lessens many health risks, including cardiovascular risks, although such improvements are most notably demonstrable in studies specifically conducted in high-risk populations, and the benefits are presumed to be greater when healthier weight is maintained for long periods.9,10 In overweight and obese individuals, weight loss achieved with most interventions over 1 to 2 years generally leads to improvements in blood pressure (BP), glycemic measures, and triglycerides (TGs). Improvements in total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) have been reported in studies using dietary interventions combined with exercise. When weight loss is achieved primarily via pharmacological interventions, these benefits have not occurred quite so consistently.11 Reduced caloric intake and increased physical activity are generally accepted as the foundations of any approach directed at weight reduction, but these lifestyle interventions do not appear to provide long-lasting success for obese individuals wishing to lose weight. About half of the weight lost with the help of lifestyle interventions is regained at 1 year; after …

Reporting Quality of Marginal Rates of Substitution in Discrete Choice Experiments That Elicit Patient Preferences.

We compared the effects of aerobic exercise training on lipid and lipoprotein levels in 18 postmenopausal women who were (N = 8) or were not (N = 10) receiving estrogen replacement therapy (ERT). Each group was tested for lipids, diet recall and VO2max before and after a 12 wk exercise program, consisting of 30-50 min of an aerobic activity at 75-85% of VO2max, 3-4 sessions per week. Both groups increased VO2max by 8% and neither group changed their diet. The ERT group had higher levels of triglycerides and lower levels of low density lipoprotein (LDL-C) (P < 0.01) before training. There were no mean group changes in any of the lipid variables with training. However, individual changes in LDL-C and Total Cholesterol (TC) were strongly related to baseline weight in the nonestrogen group (r = 109.91, r = -0.82) but not in ERT (r = -0.30, r = -0.51). Subsequently, all subjects were redivided into two groups based on BMI (< or = 27 or > or = 27) regardless of ERT status. TC decreased significantly (P < 0.05) in the < or = 27 BMI group. Exercise training had little effect on the lipid profiles of the ERT and the nonestrogen groups, but body weight seems to be a modulating factor. Heavier subjects did not respond as favorably to 12 wk of exercise training as postmenopausal women with less body mass, regardless of the presence of exogenous estrogen.

Background: Advanced treatment options for non-small cell lung cancer (NSCLC) consist of immunotherapy, chemotherapy, or a combination of both. Decisions surrounding NSCLC can be considered as preference-sensitive because multiple treatments exist that vary in terms of mode of administration, treatment schedules, and benefit–risk profiles. As part of the IMI PREFER project, we developed a protocol for an online preference survey for NSCLC patients exploring differences in preferences according to patient characteristics (preference heterogeneity). Moreover, this study will evaluate and compare the use of two different preference elicitation methods, the discrete choice experiment (DCE) and the swing weighting (SW) task. Finally, the study explores how demographic (i.e., age, gender, and educational level) and clinical (i.e., cancer stage and line of treatment) information, health literacy, health locus of control, and quality of life may influence or explain patient preferences and the usefulness of a digital interactive tool in providing information on preference elicitation tasks according to patients.Methods: An online survey will be implemented with the aim to recruit 510 NSCLC patients in Belgium and Italy. Participants will be randomized 50:50 to first receive either the DCE or the SW. The survey will also collect information on participants' disease-related status, health locus of control, health literacy, quality of life, and perception of the educational tool.Discussion: This protocol outlines methodological and practical steps to quantitatively elicit and study patient preferences for NSCLC treatment alternatives. Results from this study will increase the understanding of which treatment aspects are most valued by NSCLC patients to inform decision-making in drug development, regulatory approval, and reimbursement. Methodologically, the comparison between the DCE and the SW task will be valuable to gain information on how these preference methods perform against each other in eliciting patient preferences. Overall, this protocol may assist researchers, drug developers, and decision-makers in designing quantitative patient preferences into decision-making along the medical product life cycle.

Background and ObjectivesCase 2 best-worst scaling (BWS-2) is an increasingly popular method to elicit patient preferences. Because BWS-2 potentially has a lower cognitive burden compared with discrete choice experiments, the aim of this study was to compare treatment preference weights and relative importance scores.MethodsPatients with neuromuscular diseases completed an online survey at two different moments in time, completing one method per occasion. Patients were randomly assigned to either first a discrete choice experiment or BWS-2. Attributes included: muscle strength, energy endurance, balance, cognition, chance of blurry vision, and chance of liver damage. Multinomial logit was used to calculate overall relative importance scores and latent class logit was used to estimate heterogeneous preference weights and to calculate the relative importance scores of the attributes for each latent class.ResultsA total of 140 patients were included for analyses. Overall relative importance scores showed differences in attribute importance rankings between a discrete choice experiment and BWS-2. Latent class analyses indicated three latent classes for both methods, with a specific class in both the discrete choice experiment and BWS-2 in which (avoiding) liver damage was the most important attribute. Ex-post analyses showed that classes differed in sex, age, level of education, and disease status. The discrete choice experiment was easier to understand compared with BWS-2.ConclusionsThis study showed that using a discrete choice experiment and BWS-2 leads to different outcomes, both in preference weights as well as in relative importance scores, which might have been caused by the different framing of risks in BWS-2. However, a latent class analysis revealed similar latent classes between methods. Careful consideration about method selection is required, while keeping the specific decision context in mind and pilot testing the methods.

A reduced level of high-density lipoprotein cholesterol (HDL-C) is a powerful independent risk factor for the development and progression of coronary heart disease. This study assessed the effects of cardiac rehabilitation exercise training on HDL-C and other lipid subfractions, giving close attention to the role of gender and baseline values. The study population consisted of 340 patients with coronary heart disease who enrolled in outpatient cardiac rehabilitation and completed 36 sessions of exercise over a 12-week period. With the National Cholesterol Education Panel ATP III guidelines used to create categories of HDL-C, patients were stratified at baseline into four subgroups: (1) males with high HDL-C, (2) males with low HDL-C, (3) women with high HDL-C, and (4) women with low HDL-C. Overall, women experienced a significantly greater improvement in HDL-C after exercise training than men (14% vs 7.1%; P <.0001). Among the patients with a high HDL-C at baseline, the women increased HDL-C by 8.4%, whereas there was no change (0.9%) in the men (P <.001 between groups). Additionally, the women with low HDL-C experienced a significantly greater improvement than the men (15.3% vs 11.5%, P <.03). The study results demonstrate that women experience a greater improvement in HDL-C with cardiac rehabilitation than men despite similar changes in fitness and body composition. Women, regardless of baseline HDL-C, demonstrated improvements in HDL-C, whereas only men with low HDL-C experienced an increase in HDL-C. These results describe a differing impact of cardiac rehabilitation on changes in HDL-C based on gender. Clinicians should consider the impact of gender when assessing an individual's risk factor goals and therapeutic options.

80 Background: Nine new treatments for mCRPC, each varying in efficacy and safety, have been approved over the last 10 years, changing the landscape of patient management. Understanding how patients perceive and value the efficacy, safety, and administration burden of these treatments can facilitate shared-decision making to determine optimal management. To our knowledge, this study is the first to elicit patient preferences for mCRPC treatments in the US. Methods: We conducted a cross-sectional survey using the discrete-choice experiment (DCE) method, in which participants were asked to state their choices over successive sets of treatment alternatives, defined by varying levels of treatment characteristics (i.e., attributes). Six treatment attributes in this DCE were examined: overall survival (OS), months until patients develop a fracture or bone metastasis, likelihood of requiring radiation to control bone pain, fatigue, nausea, and mode of administration. The levels taken by each of these attributes were selected to reflect clinical practice. Quota sampling was used in an online panel for recruitment to ensure that study sample is representative of the US prostate cancer population by age distribution. The choice responses were used to determine the value (i.e., preference weights) respondents placed on each attribute via the use of conditional and mixed logit models. The importance of attributes and marginal rates of substitutions were also calculated in order to understand how much patients were willing to trade off between different attributes. Results: The final dataset included 160 participants, with a mean age of 71.6 years old and a mean of 8.96 years since prostate cancer diagnosis. Participants noted their preferences for mCRPC treatments characteristics as follows (in decreasing order of importance over the attribute ranges included in the study): OS (relative attribute importance [RAI]: 31%), reduction in the need for bone pain control (23%), nausea (16%), months until patients develop a fracture or bone metastasis (15%), fatigue (11%), and mode of administration (3%). The marginal rates of substitution demonstrated that eliminating moderate nausea was perceived as equivalent to a 1.9-month reduction in OS, and a reduction of fatigue from severe to mild was perceived as equivalent to a reduction in OS of approximately 3.3 months. Conclusions: Improving OS remains the highest priority, but patients are willing to sacrifice some survival to avoid declines in quality of life, including avoiding bone pain/fracture, nausea, and fatigue, in the mCRPC disease state.

Patients often experience challenges accessing physical therapy for breast cancer-related impairments. Eliciting patient preferences for physical therapy can inform design of patient-centered, breast cancer-focused physical therapy programming. A discrete choice experiment (DCE) was used to elicit patient preferences for physical therapy after breast cancer surgery. Sequential mixed methods identified 7 attributes of physical therapy: education timing; referral method; first appointment timing; physical therapist expertise level; treatment format; treatment frequency; and annual out-of-pocket cost. Respondents chose between 2 physical therapy programs and an opt-out option. The DCE was administered online. Participants were adults with breast cancer in Canada. Responses were analyzed using a mixed logit model. Willingness-to-pay estimates were calculated as the marginal rate of substitution between each attribute level with respect to cost. The DCE was completed by 148 respondents (completion rate: 77.5%). Most were within 3years post-diagnosis (54.1%), had completed post-secondary education (70.9%), and had annual family incomes over $40,000 (76.5%). Nearly half were referred to physical therapy (48.5%). Respondents preferred to be seen by a physical therapist with expertise in breast cancer (β= .368, SD = 0.091) and to receive more frequent appointments (β= -.011, SD = 0.025). The DCE was capable of eliciting patient preferences for physical therapy after breast cancer surgery. Respondents exhibited preferences for physical therapist expertise level and treatment frequency. Findings from this study will be the first step in informing development of accessible physical therapy programming that is responsive to the needs and preferences of patients with breast cancer. This work can inform design of accessible, patient-centered physical therapist services for patients with breast cancer. Receiving timely physical therapy can improve patients' physical function, quality of life, and ability to engage in life roles and activities.

Discrete choice experiments are increasingly used to assess preferences for vaccines and vaccine service delivery. To synthesize and critically assess the application of discrete choice experiments in childhood/adolescent vaccines, to describe how discrete choice experiments have been applied to understand preferences, and to evaluate the use of discrete choice experiment data to inform estimates of vaccine uptake. We conducted a systematic review of six electronic databases. Included studies were discrete choice experiments and conjoint analyses published from 2000 to 2016 related to childhood/adolescent vaccines where respondents were parents, children/adolescents, or service providers. Validity assessment was used to assess study quality and risk of bias. In total, 27 articles were included, representing 21 different studies. A majority of articles were published between 2011 and 2016. Vaccines studied included human papillomavirus (24%), influenza (19%), meningococcal vaccines (14%), childhood vaccines (14%), hypothetical vaccines (10%), hepatitis B (5%), and diphtheria, tetanus, pertussis, hepatitis B, poliomyelitis, and Haemophilus influenzae type b (5%). Most studies assessed parent preferences (67%). The most common attributes were risk (24%), degree/duration of protection (21%), and cost (15%). Commonly reported outcome measures were estimates of uptake (33%), willingness-to-pay (22%), and other marginal rates of substitution (14%). Validity assessments yielded high scores overall. Areas of weakness included low response rates, inefficient experimental design, and failure to conduct formative qualitative work and a pilot of the discrete choice experiment. This is the first systematic review of childhood/adolescent vaccine-related discrete choice experiments. In future, special attention should be paid to ensuring that choice context and discrete choice experiment design are compatible to generate reliable estimates of uptake.

Developing a Cerebral Palsy Preference Based Utility Measure using a Discrete Choice Experiment for cost-utility analyses

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

Objective This paper describes the application of discrete choice experiments (DCEs), in the measurement of consumers' preferences for pharmacy services. Summary Patients' preferences for healthcare influence strongly their use of services. Quantifying revealed preferences for services (what services people use) is not always possible because either the service does not yet exist or the consumer has no experience of it. There is a need for tools that measure stated preference (what people say they will do) for healthcare, to allow development of new services. DCEs have been used in the valuation of preferences for healthcare services and interventions and can be applied usefully to the valuation of preferences for pharmacy services. DCEs assume that preferences are based on preferences for different attributes of a service, and that consumers are prepared to trade off one attribute against another, such as effectiveness versus side-effects. In a DCE study, respondents make hypothetical choices between scenarios of services with fixed attributes, but varying levels, revealing their strength of preference for attributes of that service. These data are analysed using regression, which generates coefficients that quantify the direction and magnitude of preferences. Marginal rates of substitution and willingness to pay for each attribute can be estimated, which provide powerful information for future service provision. For this approach to be applied in practice, key methodological issues must be handled explicitly, principally scenario design, attribute and level selection, orthogonality, level balance, minimal overlap and utility balance. A hypothetical example of a DCE designed for valuing consumers' preferences for a medication review service for the elderly is described.

Oral HIV pre-exposure prophylaxis (PrEP) is highly effective, but adherence is challenging for young women. Products centred around women's preferences could address adherence barriers. Using a longitudinal discrete choice experiment (DCE), we examined young African women's preferences around PrEP product formulation and delivery attributes before and after initiating oral PrEP. We enrolled HIV-negative women from six African countries in a prospective cohort from August 2022 to June 2023. Women completed two DCEs on PrEP products and PrEP delivery. At enrolment and month 1, participants completed the DCE about PrEP products with 16 randomly assorted choice sets assessing product form and dosing, dose forgiveness, drug reversibility, weight change and antiretroviral or immune-based mechanism attributes. At month 3, participants completed the DCE about PrEP delivery evaluating preferences related to location to collect doses, packaging, product storage, type of HIV test andcosts. Preference weights (PW) were estimated with a hierarchical Bayesian model; higher positive numbers indicate greater preference for an attribute. Importance scores compare relative importance across the five attributes; higher scores indicate greater importance. Two thousand eight hundred and forty-seven women completed enrolment and month 1 DCEs; the median age was 24 years (range: 16-30) and 92.8% initiated daily oral PrEP. Product form and dosing was the most important attribute at enrolment and month 1. At enrolment, women preferred small oral pills taken monthly (preference weight [PW]: 0.67; 95% confidence interval [CI]: 0.58-0.77), and at month 1, they preferred a 6-monthly injection (PW: 0.56; 95% CI: 0.46-0.65). In the month 3 DCE, location was the most important PrEP delivery attribute with a strong preference for a youth-friendly or non-governmental organization (PW: 0.25; 95% CI: 0.19-0.30) or health facility (PW: 0.21; 95% CI: 0.17-0.25); mobile clinic or van was least preferred. The cost of the product was the second most important product delivery attribute. Young African women preferred discreet, less frequently administered PrEP formulations, particularly after 1 month of taking daily oral PrEP. Long-acting formulations are needed to meet women's preferences. Coupled with the preferred PrEP delivery location and cost, the highlighted PrEP product characteristics have the potential to increase PrEP uptake.

Objective: Fabry disease is a rare inherited lysosomal storage disorder caused by deficiency of α-galactosidase A. Effective enzyme replacement therapies are available that are administered intravenously. However, a new oral treatment is being developed as an alternative option for patients with amenable mutations. This study was designed to understand the value that people place on the different features of treatments for Fabry disease.Research design and methods: A discrete choice experiment (DCE) was designed to assess the importance of different aspects of treatments for Fabry disease. The attributes included overall survival, mode of administration, treatment related reactions, treatment related headaches and risk of antibody formation. Attributes were combined using a published orthogonal array into choice sets. A research panel was used to survey the UK general public. The mixed logit model was used to estimate strength of preference for the attributes and marginal rates of substitution (MRSs). Disutilities were estimated from the DCE data for changes in each attribute.Results: The sample (n = 506) was broadly representative of UK demographics. The logit model revealed that all attributes were significant predictors of choice. Participants were significantly more likely to choose a treatment which meant an increase in their life expectancy by 1 year (odds ratio = 1.574; 95% CI = 1.504–1.647) and significantly less likely to choose self-administered intravenous (IV) treatment compared to an every other day tablet (OR = 0.426 95% CI = 0.384–0.474). Estimated disutilities were −0.0543 (self-administered infusion), treatment related headaches 12 times a year (−0.0361) and infusion reactions six times a year (−0.0202).Conclusions: The survey revealed a significant preference for oral treatment compared with IV even in the context of a treatment that can extend overall survival. MRSs were used as a basis for estimating disutilities associated with changes in attribute levels which could be used to weight QALYs. It is possible that other important treatment attributes are missing from this research which may have provided further insights. It would also be useful to extend this research to include Fabry disease patients so their preferences can be assessed against the societal perspective.

PNS203 USE OF DISCRETE CHOICE EXPERIMENTS TO INFORM HTA DECISION MAKING.