Comparing preferences for outcomes of psoriasis treatments among patients and dermatologists in the U.K.: results from a discrete-choice experiment

Evaluating Treatment Choice in Patients with Moderate to Severe Psoriasis in the United States: Results from a US Patient Survey

INTRODUCTION

While multiple treatments are available for moderate to severe psoriasis, patient preferences are rarely systematically studied. This study aims to identify factors associated with choice of a new once-daily oral psoriasis treatment, elicit patient views on treatment characteristics, and rank treatment characteristics by importance.

METHODS

This noninterventional, cross-sectional survey study, conducted from December 2021 to June 2022, recruited US adults with moderate to severe psoriasis. Demographics, clinical characteristics, and perspectives on psoriasis treatment were collected. Factors associated with the choice of a new oral treatment were identified using multivariable logistic regression analysis. Treatment characteristics and reasons for treatment choice were ranked using bivariate comparisons.

RESULTS

The study included 882 participants [mean (standard deviation; SD) age, 45.7 (12.8) years; female, 67.7%; White, 74.9%]; 92.7% were currently receiving treatment [mean (SD) duration, 2.9 (4.8) years]. Half of participants rated their psoriasis symptoms over the past week as mild, very mild, or nonexistent; 36.5% as moderate; and 12.7% as severe or very severe. Most (66.5%) indicated willingness to start a new oral treatment; 65.0% indicated that the new oral treatment would cause less anxiety than injections/infusions. Participants were significantly more likely to start the new oral treatment if they were currently receiving a tumor necrosis factor inhibitor [odds ratio (OR): 2.1, 95% confidence interval (CI): 1.4-3.1] or ustekinumab (OR: 2.7, 95% CI: 1.6-5.0) versus apremilast (P < 0.001) or if they reported mild (OR: 3.2, 95% CI: 2.0-4.9), moderate (OR: 5.0, 95% CI: 3.1-8.2), or severe (OR: 7.6, 95% CI: 3.9-15.0) psoriasis symptoms compared with those who reported no symptoms in the past week (P < 0.001).

CONCLUSION

Most participants indicated willingness to start a new once-daily oral treatment, viewing it as less anxiety provoking than injections/infusions. Current treatment and psoriasis severity affected participants' willingness to start a new oral treatment.

Illustrating Emerging Good Practices for Quantitative Benefit-Risk Assessment: A Hypothetical Case Study of Systemic Biologic Treatments for Plaque Psoriasis

OBJECTIVES

Quantitative benefit-risk assessment (qBRA) is a structured process to evaluate the benefit-risk balance of treatment options to support decision making. The ISPOR qBRA Task Force was recently established to provide recommendations for the design, conduct, and reporting of qBRA. This report presents a hypothetical case study illustrating how to apply the Task Force's recommendations toward a qBRA to inform the benefit-risk assessment of brodalumab at the time of initial marketing approval. The qBRA evaluated 2 dosing regimens of brodalumab (210 mg or 140 mg twice weekly) compared with weight-based dosing of ustekinumab and placebo.

METHODS

We followed the 5 steps recommended by the Task Force. Attributes included treatment response (≥75% improvement in Psoriasis Area and Severity Index), suicidal ideation and behavior, and infections. Performance data were drawn from pivotal clinical trials of brodalumab. The qBRA used multicriteria decision analysis and preference weights from a hypothetical discrete choice experiment. Sensitivity analyses examined the robustness of benefit-risk ranking to uncertainty in clinical effect and preference estimates, consideration of a subgroup (nail psoriasis), and the maintenance phase of treatment (52 weeks instead of 12).

RESULTS

Results from this hypothetical qBRA suggest that brodalumab 210 mg had a more favorable benefit-risk profile compared with ustekinumab and placebo. Ranking of brodalumab compared with ustekinumab was dependent on brodalumab's dose. Sensitivity analyses demonstrated robustness of benefit-risk ranking to uncertainty in clinical effect and preference estimates, as well as choice of attributes and length of follow-up.

CONCLUSION

This case study demonstrates how to implement the ISPOR Task Force's good practice recommendations on qBRA.

Exploring the perspective of patients with immune-mediated inflammatory diseases and care providers on the use of immunomodulatory drugs in infections: an interview study

Objectives

Immunomodulatory agents are safe and effective as treatment for various immune-mediated inflammatory diseases (IMIDs), but are associated with a slightly increased infection risk. It is uncertain whether, in the event of an infection, continuation or temporary interruption of immunomodulatory agents leads to better outcomes. Owing to this uncertainty, it is of importance to explore the perspectives of health-care providers (HCPs) and patients on this topic. In this study, we set out to identify and provide an overview of reasons for both treatment strategies.

Methods

Semi-structured interviews were conducted with HCPs involved in the pharmacological treatment of IMIDs and with IMID patients using one or more immunomodulatory agent. Purposive sampling was used to enrich data variation. Interviews were conducted until data saturation was reached and subsequently analysed using qualitative content analysis.

Results

In total, 13 HCPs and 19 IMID patients were interviewed. A wide range of reasons for both treatment strategies were identified, categorized into 10 overarching themes, including IMID characteristics, infection characteristics and the patient-HCP relationship.

Conclusion

In this interview study, we identified various reasons for continuation or temporary interruption of immunomodulatory agents during infections for both IMID patients and HCPs. We found overlapping themes, such as IMID characteristics; however, the content and interpretation of these themes might differ between HCPs and patients. Both HCPs and patients mentioned that the decision for a treatment strategy is often about weighing benefits against risks (e.g. infection severity vs disease flare).

Prescribing antibiotics: Factors driving decision-making in general practice. A discrete choice experiment

BACKGROUND

Antimicrobial resistance is a threat to human health. We need to strive for a rational use of antibiotics to reduce the selection of resistant bacteria. Most antibiotics are prescribed in general practice, but little is known about factors influencing general practitioners' (GPs) decision-making when prescribing antibiotics.

AIM

To 1) assess the importance of factors that influence decisions by GPs to prescribe antibiotics for acute respiratory tract infections (RTIs) and 2) identify segments of GPs influenced differently when deciding to prescribe antibiotics.

METHODS

A questionnaire survey including a discrete choice experiment was conducted. Danish GPs were asked to indicate whether they would prescribe antibiotics in six hypothetical choice sets with six variables: whether the GP is behind schedule, patient's temperature, patient's general condition, lung auscultation findings, C-reactive protein (CRP) level, and whether the patient expects antibiotics. Error component and latent class models were estimated and the probabilities of prescribing in different scenarios were calculated.

RESULTS

The questionnaire was distributed to every Danish GP (n = 3,336); 1,152 (35%) responded. Results showed that GPs were influenced by (in prioritised order): CRP level (Relative importance (RI) 0.54), patient's general condition (RI 0.20), crackles at auscultation (RI 0.15), and fever (RI 0.10). Being behind schedule and patient expectations had no significant impact on antibiotic prescription at the aggregate level. The latent class analysis identified five classes of GPs: generalists, CRP-guided, general condition-guided, reluctant prescribers, and stethoscopy-guided. For all classes, CRP was the most important driver, while GPs were heterogeneously affected by other drivers.

CONCLUSION

The most important factor affecting Danish GPs' decision to prescribe antibiotics at the aggregate level, in subgroups of GPs, and across latent classes was the CRP value. Hence, the use of CRP testing is an important factor to consider in order to promote rational antibiotic use in the battle against antimicrobial resistance.

The Impact of the Risk Functional Form Assumptions on Maximum Acceptable Risk Measures

BACKGROUND

Discrete-choice experiments (DCEs) are increasingly conducted to quantify risk tolerance by computing maximum acceptable risk (MAR) for improvements in efficacy or other benefits gained from new medical treatments. To compute MARs from DCE data, respondents are asked to make choices under uncertainty between treatments. Specific treatment-related harms are included in the choice questions as probabilistic adverse events (AEs), and choice variation with the probability of these outcomes is assumed to indicate their effect on the expected utility of treatments. With a limited number of comparisons between profiles, calculation of MARs requires understanding how outcome probabilities that are not explicitly considered in the DCE can change the value of medical technologies. This study aims to examine how various assumptions on the expected disutility of these excluded probabilities can result in different MAR measures.

METHODS

We summarize commonly used empirical specifications for the expected disutility of AEs and derive the resulting MAR functions. We then discuss an empirical application on treatments to delay bone metastases in oncology patients with solid tumors.

RESULTS

A total of 187 respondents completed the DCE. Results show the impact of making various assumptions about the expected disutility of AEs, and the resulting MAR values for specific health benefits. As expected, different assumptions resulted in variations in MAR values for specific health benefits. Even with small differences in MAR measures, our results suggest that the assumptions evaluated here can lead to different conclusions about the acceptability of a medical technology.

CONCLUSION

Results show possible systematic variations in MARs caused by the assumed form of the effect of changes in the probability of AEs. Furthermore, we find that different assumptions can lead to different conclusions about the acceptability of a medical technology, even when MAR distributions overlap. This result suggests that researchers should evaluate the assumptions they are making for these effects and use sensitivity analysis to evaluate the robustness of risk-tolerance measures from stated-preference data.

Exploring determinants of psoriasis patients' treatment choices: a discrete-choice experiment study in the United States and Germany

BACKGROUND

Biologic psoriasis treatments are differentiated by efficacy, side effects, and other attributes.

OBJECTIVE

Determine attributes of biologic psoriasis treatments that drive patients' treatment choices.

METHODS

Respondents (USA: n = 300; Germany: n = 300) with moderate-to-severe psoriasis completed a discrete-choice-experiment survey, choosing between hypothetical treatments characterized by attributes with varying levels: chance of clear skin after 1 year, number of first-year treatments, first-year risks of mild-to-moderate injection site reaction (ISR) and serious infection, and years of proven efficacy/safety.

RESULTS

U.S. respondents most valued clear skin (conditional relative importance, 1.88; p < .05). While other attributes were of generally equivalent importance, ISR risk outweighed serious-infection risk (1.06 vs. 0.70; p < .05). German respondents placed greatest importance on ISR risk (1.61; p < .05) and clear skin (1.49; p < .05).

LIMITATIONS

Respondents evaluated hypothetical treatments and were recruited from web panels.

CONCLUSIONS

Clear skin and ISR risk are stronger drivers of treatment choice than injection frequency and infection risk.

Opening the 'Black Box': An Overview of Methods to Investigate the Decision-Making Process in Choice-Based Surveys

The desire to understand the preferences of patients, healthcare professionals and the public continues to grow. Health valuation studies, often in the form of discrete choice experiments, a choice based survey approach, proliferate as a result. A variety of methods of pre-choice process analysis have been developed to investigate how and why people make their decisions in such experiments and surveys. These techniques have been developed to investigate how people acquire and process information and make choices. These techniques offer the potential to test and improve theories of choice and/or associated empirical models. This paper provides an overview of such methods, with the focus on their use in stated choice-based healthcare studies. The methods reviewed are eye tracking, mouse tracing, brain imaging, deliberation time analysis and think aloud. For each method, we summarise the rationale, implementation, type of results generated and associated challenges, along with a discussion of possible future developments.

Impact of clinical and demographic characteristics on patient preferences for psoriasis treatment features: Results from a discrete-choice experiment in a multicountry study

OBJECTIVES

This study aimed to elicit preferences for psoriasis treatment features and to test for preference heterogeneity across groups of respondents.

MATERIALS AND METHODS

A discrete-choice experiment was employed to elicit preferences of patients with plaque psoriasis in multiple countries. The survey instrument included a series of choice questions between three hypothetical treatments, each characterized by varying levels of six attributes (namely, lesion reduction, risk of impairing side effects, time to reach results, mode and frequency of administration, itching reduction, and side effects). Random parameters logit was used to model the data. Results were compared across a total of 18 subgroup sets.

RESULTS

The data analysis from 1,123 respondents showed that, on average, respondents receive more utility gain from higher levels of lesion reduction and lower risks of impairing side effects than changes in other attributes included in the study. Systematic differences were detected for 13 sets; the most pronounced differences were observed based on disease severity, nail psoriasis, biologic experience, and quality-of-life scores.

CONCLUSION

These many sources of preference heterogeneity identified by our analysis suggest that to improve patient satisfaction and, probably, adherence and persistence, clinicians should discuss options with patients when prescribing their treatment.

The importance of understanding patient and physician preferences for psoriasis treatment characteristics: a systematic review of discrete-choice experiments

Introduction: Treatment adherence continues to be a major challenge in psoriasis. Patient preference studies, especially discrete-choice experiments, are gaining popularity to gather insights into patient reported treatment outcomes. This systematic literature review aimed to critically assess all discrete choice experiments exploring patients' and physicians' preferences for psoriasis treatment characteristics.Methods: PubMed and EMBASE databases were searched using keywords "psoriasis" and "preferences" to identify relevant literature. Discrete-choice experiments conducted in French or English from the year 2000 onwards, that focused on evaluating psoriasis treatment preferences in patients and/or physicians, were included. The relative importance of treatment attributes was assessed and studies were critically appraised using validated checklists.Results: Out of 987 articles identified, 25 articles fulfilled the inclusion criteria. Overall, patients and physicians prioritize efficacy-specific outcomes. Patients are shown to place greater importance to process attributes when compared to physicians, especially route and location of administration. Physicians focus primarily of efficacy attributes, however when the top two attributes are considered, safety outcomes increasingly become considered important. Of the studies, 60% conducted subgroup analysis, of which many reported associations between specific patient characteristics and preferences. Factors such as age, disease severity, and duration of condition significantly affected preferences for treatment attributes.Conclusions: This review provides insight into the types of attributes that patients and physicians value most, and therefore can help improve shared decision-making. The findings of this study also encourage regulatory agencies to continue integrating patient preferences in their decision-making.

Patient-physician discrepancy in the perception of immune-mediated inflammatory diseases: rheumatoid arthritis, psoriatic arthritis and psoriasis. A qualitative systematic review of the literature

Introduction

Recommendations on chronic diseases management emphasise the need to consider patient perspectives and shared decision-making. Discrepancies between patients and physicians’ perspectives on treatment objectives, disease activity, preferences and treatment have been described for immune-mediate inflammatory diseases. These differences could result on patient dissatisfaction and negatively affect outcomes.

Objective

To describe the degree of patient-physician discrepancy in three chronic immune-mediated inflammatory diseases (rheumatoid arthritis [RA], psoriatic arthritis [PsA] and psoriasis [Ps]), identifying the main areas of discrepancy and possible predictor factors.

Methods

Qualitative systematic review of the available literature on patient and physician discrepancies in the management of RA, PsA and Ps. The search was performed in international (Medline/PubMed, Cochrane Library, ISI-WOK) and Spanish electronic databases (MEDES, IBECS), including papers published from April 1, 2008 to April 1, 2018, in English or Spanish, and conducted in European or North American populations. Study quality was assessed by the Oxford Centre for Evidence-Based Medicine criteria.

Results

A total of 21 studies were included (13 RA; 3 PsA; 4 Ps; 1 RA, Ps, and Axial Spondyloarthritis). A significant and heterogeneous degree of discrepancy between patients and physicians was found, regarding disease activity, treatment, clinical expectations, remission concept, and patient-physician relationship. In RA and PsA, studies were mainly focused on the evaluation of disease activity, which is perceived as higher from the patient’s than the physician’s perspective, with the discrepancy determined by factors such as patient’s perception of pain and fatigue. In Ps, studies were focused on treatment satisfaction and patient-physician relationship, showing a lower degree of discrepancy in the satisfaction regarding these aspects.

Conclusions

There is a significant degree of patient-physician discrepancy regarding the management of RA, PA, and Ps, what can have a major impact on shared decision-making. Future research may help to show whether interventions considering discrepancy improve shared decision-making.

Modeling Heterogeneity in Patients' Preferences for Psoriasis Treatments in a Multicountry Study: A Comparison Between Random-Parameters Logit and Latent Class Approaches

BACKGROUND

Either a random-parameters logit (RPL) or latent class (LC) model can be used to model or explain preference heterogeneity in discrete-choice experiment (DCE) data. The former assumes continuous distribution of preferences across the sample, while the latter assumes a discrete distribution. This study compared RPL and LC models to explore preference heterogeneity when analyzing patient preferences for psoriasis treatments.

METHODS

Using DCE data collected from respondents with moderate-to-severe plaque psoriasis, we calculated and compared preference weights derived from RPL and LC models. We then compared how RPL and LC explain preference heterogeneity by exploring differences across subgroups defined by observed characteristics (i.e., country, age, gender, marital status, and psoriasis severity).

RESULTS

While RPL and LC models resulted in the same mean preference weights, different preference-heterogeneity patterns emerged from the two approaches. In both models, country of residence and self-reported disease severity could be linked to systematic differences in preferences. The RPL also identified gender and marital status, but not age, as sources of heterogeneity; the LC membership probability model indicated that age was a significant factor, but not gender or marital status.

CONCLUSIONS

Using data from a psoriasis patient survey to compare two widely used methods for exploring heterogeneity identified differences in results between stated-preferences: subgroup analysis in the RPL model and inclusion of subgroup characteristics in the class membership probability function of the LC model. Researchers should model data using the most adaptable approach to address the initial study question.

Feasibility and Utility of the Psoriasis Symptom Inventory (PSI) in Clinical Care Settings: A Study from the International Psoriasis Council

Background

The Psoriasis Symptom Inventory (PSI) is a patient-reported outcome measure designed to assess psoriasis signs and symptoms.

Objectives

The aim was to assess the usefulness of the PSI in enhancing patient care in the clinical setting.

Methods

Eight dermatology clinics in six countries enrolled adults representing the full spectrum of psoriasis severity who regularly received care at the clinic. Patients were administered the eight-item PSI (score range 0–32; higher scores indicate greater severity) while waiting for the physician; the physician conducted a static physician global assessment (sPGA) and estimated psoriasis-affected body surface area (BSA) at the same visit. Physicians completed a brief questionnaire after each patient visit, and were interviewed about the PSI after all patients were seen.

Results

The clinics enrolled 278 patients; mean [standard deviation (SD)] psoriasis-affected BSA was 7.6% (11.4). Based on BSA, 47.8% had mild psoriasis, 29.1% had moderate psoriasis, and 23.0% had severe psoriasis. Based on sPGA, 18.7% were clear/almost clear, 67.3% were mild/moderate, and 14.0% were severe/very severe. The mean (SD) PSI total score was 12.2 (8.3). Physicians spent a mean (SD) 4.9 (4.8) min discussing PSI findings with their patients (range 0–20 min). Key benefits of PSI discussions included the following: new information regarding symptom location and severity for physicians; prompting of quality-of-life discussions; better understanding of patient treatment priorities; change in treatment regimens to target specific symptoms or areas; and improvement of patient–physician relationship.

Conclusions

The PSI was useful for treated and untreated patients to enhance patient–physician communication, and influenced treatment decisions.

Electronic supplementary material

The online version of this article (10.1007/s40257-019-00458-2) contains supplementary material, which is available to authorized users.

Patient and Physician Preferences for Therapy Characteristics for Psoriasis: A Discrete Choice Experiment in Japan

BACKGROUND

With progress being made in the treatment of psoriasis, a variety of clinical research and treatment options are being pursued. This study used a discrete choice experiment (DCE) to estimate treatment characteristic preferences for both patients and physicians in Japan. Subgroup analysis was also applied in order to examine differences within the range of patients and within the range of physicians.

METHODS

The DCE was developed with the input of clinical experts in the treatment of psoriasis to ensure inclusion of the most relevant attributes at appropriate levels in a way that is understandable to both physicians and patients. The study was conducted on parallel samples of Japanese physicians (n = 161) and Japanese psoriasis patients (n = 306) through an online panel. For each sample, a conditional logit statistical model and subgroup analysis were then performed to estimate respondent preferences for treatment attributes.

RESULTS

The overall findings are that better treatment efficacy as measured by proportion of patients achieving 90% reduction in the Psoriasis Area and Severity Index score (PASI 90), lower risk of adverse events and the availability of a bio-holiday are important decision factors for both patients and physicians. Low injection frequency is less of a priority for both samples. Also, while both groups demonstrate a preference to receive the treatment injections at a clinic by a healthcare professional rather than self-injection at home, this is more pronounced for the patient sample. The physician sample shows considerably more emphasis on the type of injection, though both samples prefer subcutaneous injections to intravenous injections.

IMPLICATIONS

This study reveals the importance of addressing both clinical effectiveness and process factors in systemic, non-topical psoriasis treatments to gain acceptance by both physicians and patients. As well as efficacy (as measured by PASI 90), which remains a consistent priority in treatment, administration and development of new treatments should also consider process factors such as the mode of administration and possibility for a bio-holiday.

Methods for exploring and eliciting patient preferences in the medical product lifecycle: a literature review

Preference studies are becoming increasingly important within the medical product decision-making context. Currently, there is limited understanding of the range of methods to gain insights into patient preferences. We developed a compendium and taxonomy of preference exploration (qualitative) and elicitation (quantitative) methods by conducting a systematic literature review to identify these methods. This review was followed by analyzing prior preference method reviews, to cross-validate our results, and consulting intercontinental experts, to confirm our outcomes. This resulted in the identification of 32 unique preference methods. The developed compendium and taxonomy can serve as an important resource for assessing these methods and helping to determine which are most appropriate for different research questions at varying points in the medical product lifecycle.

Discrete Choice Experiments in Health Economics: Past, Present and Future

OBJECTIVES

Discrete choice experiments (DCEs) are increasingly advocated as a way to quantify preferences for health. However, increasing support does not necessarily result in increasing quality. Although specific reviews have been conducted in certain contexts, there exists no recent description of the general state of the science of health-related DCEs. The aim of this paper was to update prior reviews (1990-2012), to identify all health-related DCEs and to provide a description of trends, current practice and future challenges.

METHODS

A systematic literature review was conducted to identify health-related empirical DCEs published between 2013 and 2017. The search strategy and data extraction replicated prior reviews to allow the reporting of trends, although additional extraction fields were incorporated.

RESULTS

Of the 7877 abstracts generated, 301 studies met the inclusion criteria and underwent data extraction. In general, the total number of DCEs per year continued to increase, with broader areas of application and increased geographic scope. Studies reported using more sophisticated designs (e.g. D-efficient) with associated software (e.g. Ngene). The trend towards using more sophisticated econometric models also continued. However, many studies presented sophisticated methods with insufficient detail. Qualitative research methods continued to be a popular approach for identifying attributes and levels.

CONCLUSIONS

The use of empirical DCEs in health economics continues to grow. However, inadequate reporting of methodological details inhibits quality assessment. This may reduce decision-makers' confidence in results and their ability to act on the findings. How and when to integrate health-related DCE outcomes into decision-making remains an important area for future research.

Patient and physician preferences for attributes of biologic medications for severe asthma

OBJECTIVE

Despite the increased availability of biologic treatments indicated for severe asthma, patient and physician preferences for these medications remains largely unknown. The purpose of this study was to understand perceptions of biologic therapies, barriers to care with biologic medications, and preferences for biologic therapy attributes.

METHODS

This mixed-methods study involved quantitative surveys and qualitative telephone interviews with patients and physicians from the United States. Participants described preferences for relevant attributes, and barriers to use of biologic medications. Participants rated, ranked, and indicated importance of preferences for different levels of key attributes including: mode of administration, administration setting, dosing frequency, number of injections, and time to onset of effect. Other attributes unique to each group were also included.

RESULTS

A total of 47 patients and 25 physicians participated. Patients ranked out-of-pocket costs, mode of administration, time to onset of efficacy, and administration setting as the most important attributes. Physicians ranked mode of administration, time to onset of efficacy, dosing frequency, and insurance reimbursement/access as most important. Both groups expressed preferences for less frequent administrations (Q8W over Q4W or Q2W) (all P<0.01) and subcutaneous (SC) over intravenous injection (both P<0.0001). Key patient barriers to biologic medications include location of treatment, administration time, scheduling, cost/insurance coverage, number of injections, and mode of administration. Physicians identified patient candidacy, convincing patients, administration setting, mode of administration, cost, and administrative burden as key barriers to initiating therapy; and efficacy, speed of onset, convenience of administration, cost, and patient compliance as barriers to staying on therapy.

CONCLUSIONS

Patients and physicians expressed strong preferences for less frequent dosing, SC administration, and faster onset. Cost/insurance coverage and convenience issues were key barriers to use. Increased awareness and understanding of preferences and barriers may be useful in facilitating physician-patient conversations with the goal of individualizing treatment.

Conducting a Discrete-Choice Experiment Study Following Recommendations for Good Research Practices: An Application for Eliciting Patient Preferences for Diabetes Treatments

OBJECTIVES

To consolidate and illustrate good research practices in health care to the application and reporting of a study measuring patient preferences for type 2 diabetes mellitus medications, given recent methodological advances in stated-preference methods.

METHODS

The International Society for Pharmacoeconomics and Outcomes Research good research practices and other recommendations were used to conduct a discrete-choice experiment. Members of a US online panel with type 2 diabetes mellitus completed a Web-enabled, self-administered survey that elicited choices between treatment pairs with six attributes at three possible levels each. A D-efficient experimental design blocked 48 choice tasks into three 16-task surveys. Preference estimates were obtained using mixed logit estimation and were used to calculate choice probabilities.

RESULTS

A total of 552 participants (51% males) completed the survey. Avoiding 90 minutes of nausea was valued the highest (mean -10.00; 95% confidence interval [CI] -10.53 to -9.47). Participants wanted to avoid low blood glucose during the day and/or night (mean -3.87; 95% CI -4.32 to -3.42) or one pill and one injection per day (mean -7.04; 95% CI -7.63 to -6.45). Participants preferred stable blood glucose 6 d/wk (mean 4.63; 95% CI 4.15 to 5.12) and a 1% decrease in glycated hemoglobin (mean 5.74; 95% CI 5.22 to 6.25). If cost increased by $1, the probability that a treatment profile would be chosen decreased by 1%.

CONCLUSIONS

These results are consistent with the idea that people have strong preferences for immediate consequences of medication. Despite efforts to produce recommendations, ambiguity surrounding good practices remains and various judgments need to be made when conducting stated-preference studies. To ensure transparency, these judgments should be described and justified.

Measuring the importance of health domains in psoriasis - discrete choice experiment versus rating scales

BACKGROUND

Psoriasis affects different aspects of health-related quality of life (eg, physical, psychological, and social impairments); these health domains can be of different importance for patients. The importance of domains can be measured with the Patient Benefit Index (PBI). This questionnaire weights the achievement of treatment goals by Likert scales (0, "not important at all" to 4, "very important") using the Patient Needs Questionnaire (PNQ). Treatment goals assessed with the PBI have been assigned to five health domains; the importance of each domain can be calculated as the average importance of the respective treatment goals. In this study, the PBI approach of deriving importance weights is contrasted to a discrete choice experiment (DCE), in order to determine the importance of health domains in psoriasis, and to find if the resulting weights will differ when derived from these two methods.

METHODS

Adult patients with psoriasis completed both questionnaires (PNQ, DCE). The PBI domains were used as attributes in the DCE with the levels "did not help at all", "helped moderately", and "helped a lot".

RESULTS

Using DCE, "improving physical functioning" was the most important health domain, followed by "improving psychological well-being". Using PNQ, these domains were ranked in position two and three following "strengthening confidence in the therapy and in a possible healing". The latter was least important using DCE. The only agreement of ranking was shown in "reducing impairments due to therapy" (position four). "Improving social functioning" was ranked in position three (DCE) and five (PNQ).

CONCLUSION

Health domains have different importance to patients with psoriasis. Using PNQ or DCE to determine the importance of domains results in markedly different rankings; both approaches can thus not be considered equivalent. However, in this study, importance was assessed at the domain level in DCE and at the single item level in PNQ, which may have added to the differences.

Dermatologist and Patient Preferences in Choosing Treatments for Moderate to Severe Psoriasis

Introduction

The objective of the study was to determine the relative importance (RI) of treatment attributes psoriasis patients and physicians consider when choosing between biologic therapies based on psoriasis severity.

Methods

A discrete choice experiment (DCE) weighting preference for eight sets of hypothetical treatments for moderate or severe psoriasis was conducted. DCE hypothetical treatments were defined and varied on combinations of efficacy, safety, and dosing attributes [frequency/setting/route of administration (ROA)].

Results

When assuming moderate psoriasis in the patient DCE, ROA (RI 29%) and efficacy (RI 27%) drive treatment choices. When assuming severe disease in the DCE, patients preferred treatments with higher efficacy (RI 36%); ROA was relatively less important (RI 15%). From the physician perspective, ROA (RI 32%) and efficacy (RI 26%) were most important for moderate psoriasis patients. In the physician model for severe psoriasis, efficacy (RI 42%) was the predominant driver followed by ROA (RI 22%). Regardless of severity, probability of loss of response within 1 year was the least important factor.

Conclusions

The severity of disease is a critical element in psoriasis treatment selection. There are high levels of alignment between physician- and patient-derived preferences in biologic treatment choice selection for psoriasis.

Funding

Janssen Pharmaceuticals.