Comparing Outcomes of a Discrete Choice Experiment and Case 2 Best-Worst Scaling: An Application to Neuromuscular Disease Treatment

An Empirical Comparison of Discrete Choice Experiment and Best-Worst Scaling to Estimate Patient Preferences in Infertility Treatment in China

Background

Infertility has become a growing public health problem in China. It is important to accurately and easily obtain patient preferences. This study aimed to obtain and compare stated preference results from the perspective of infertility patients. By assessing the validity and acceptability of both methods, it provides lessons for empirical research and practical application.

Methods

Discrete choice experiments (DCE) and profile case best-worst scaling (BWS-2) are methods used to identify and weigh various criteria affecting the order of priorities. We conducted a face-to-face survey of female patients with infertility aged between 20-45 years. The survey included socio-demographic information, preference questionnaires and completion of evaluation questions. Attributes included live birth rate, pregnancy rate, degree of participation in treatment decision making, maternal complications, neonatal complications and program cost. Conditional logit models were used to analyze attribute level weights and relative importance was calculated separately.

Results

A total of 330 valid questionnaires were collected. The preferences of patients experiencing infertility were quantified through two stated preference research methods. The findings indicated that patients exhibited a preference for treatment options that were highly effective, exhibited minimal side effects, were patient-centered, and were cost-effective. The BWS-2 and DCE preference weights demonstrated high consistency, with only slight difference observed in the ranking of individual attributes within the order of relative importance. In the view of the patients, the DCE questions were perceived to be less challenging to comprehend and were therefore preferred to be completed.

Conclusion

The BWS-2 and DCE exhibit identical validity and highly consistent preference results. In the context of specific research questions, the selection of a method or the combination of methods must be suitable to the purpose of the study in order to ensure that the utility gained is maximized. Further research is required to corroborate these findings.

COVID-19 Vaccine Preferences in China: A Comparison of Discrete Choice Experiment and Profile Case Best-Worst Scaling

OBJECTIVES

Little is known about the diversity of residents' preferences for COVID-19 vaccines during the time when COVID-19 management was downgraded in China. This study aims to investigate these preferences using discrete choice experiment (DCE) and profile case best-worst scaling (BWS-2), and to assess the concordance between these two methods.

METHODS

Chinese residents recruited for the online survey were asked to evaluate COVID-19 vaccine profiles through both DCE and BWS-2 from April to July 2023. Attributes included effectiveness, duration of protection, risk of severe adverse events (degree), the total out-of-pocket (OOP) cost, brand, and the vaccination method. We utilized conditional regression and mixed logit regression models to estimate the preference levels for potential attributes. To assess preference concordance between the two methods, re-scaling and the Spearman correlation test were used. Additionally, subgroup analysis was conducted to determine the most suitable method for different population groups, categorized by vaccine hesitancy and risk level.

RESULTS

A total of 438 (71.22%) respondents were included. A similar pattern was found in the DCE and BWS-2 methods, with the respondents having a strong preference for 90% vaccine effectiveness. However, the methods diverged in other preferences; DCE favored domestic brands and low severe adverse event risk, while BWS-2 preferred moderate risk and three years of protection. Concordance assessment, including Spearman's correlation and linear regression, showed no significant correlation and poor concordance between the methods, underscoring these differences. Preference heterogeneity is revealed among different groups; however, effectiveness remained the most important attribute for all subgroups of the population. Oral vaccination was the preferred option for both the vaccine-hesitant and high-risk groups.

CONCLUSION

This study offers new insights into the varying preferences for COVID-19 vaccines among Chinese residents following the downgrading of pandemic management measures. The findings underscore the need for diverse strategies in vaccine policy design. Special emphasis should be placed on vaccine attributes that align with public priorities, such as high effectiveness and low risk levels, to enhance vaccine uptake.

Comparing the Self-Reported Acceptability of Discrete Choice Experiment and Best-Worst Scaling: An Empirical Study in Patients with Type 2 Diabetes Mellitus

Purpose

Discrete choice experiment (DCE) and profile case (case 2) best-worst scaling (BWS) present uncertainties regarding the acceptability of quantifying individual healthcare preferences, which may adversely affect the validity of responses and impede the reflection of true healthcare preferences. This study aimed to assess the acceptability of these two methods from the perspective of patients with type 2 diabetes mellitus (T2DM) and examine their association with specific characteristics of the target population.

Patients and Methods

This cross-sectional study was based on a nationally representative survey; data were collected using a multistage stratified cluster-sampling procedure between September 2021 and January 2022. Eligible adults with confirmed T2DM voluntarily participated in this study. Participants completed both the DCE and case 2 BWS (BWS-2) choice tasks in random order and provided self-reported assessments of acceptability, including task completion difficulty, comprehension of task complexity, and response preference. Logistic regression and random forest models were used to identify variables associated with acceptability.

Results

In total, 3286 patients with T2DM were included in the study. Respondents indicated there was no statistically significant difference in completion difficulty between the DCE and BWS-2, although the DCE scores were slightly higher (3.07 ± 0.68 vs 3.03 ± 0.67, P = 0.06). However, 1979 (60.2%) respondents found the DCE easier to comprehend. No significant preferences were observed between the two methods (1638 (49.8%) vs 1648 (50.2%)). Sociodemographic factors, such as residence, monthly out-of-pocket costs, and illness duration were significantly associated with comprehension complexity and response preference.

Conclusion

This study yielded contrasting results to most of previous studies, suggesting that DCE may be less cognitively demanding and more suitable for patients with T2DM from the perspective of self-reported acceptability of DCE and BWS. This study promotes a focus on patient acceptability in quantifying individual healthcare preferences to inform tailored optimal stated-preference method for a target population.

Gender preferences for multiple attributes of soil and water conservation in Northern Rwanda

Despite the dominance of female labor in agricultural production, female-controlled farm plots have lower efficiency compared to plot managed by male-headed households, which indicates a huge gender disparity in agricultural productivity. Overlooking gender preferences when designing interventions that promote the conservation of soil and water resources might face challenges in adoption and could result in ineffective policies to close the gender gap. This study seeks to analyze gender-specific preferences regarding attributes of soil and water conservation (SWC) in northern Rwanda. A best-worst survey was conducted among 653 respondents, comprising 253 males and 400 females, representing 422 households surveyed between September and December 2019. The analysis of BWS data involved assessing attribute-level relative importance, Pearson correlation, and maximum difference scaling using multinomial logit (MNL). Findings from attribute-level importance analysis revealed significant gender-based disparities in preferences across three important SWC attribute scenarios: the high scenario (between 65 % and 100 %), the moderate scenario (between 50 % and 65 %), and the basic scenario (with <50 % relative importance). The study identified heterogeneity in preferences regarding the relative importance of SWC attribute levels. Pearson correlation analysis revealed substantial synergies among attribute levels linked to land consolidation, improved land tenure, and joint SWC decision-making between genders. Additionally, the study identified trade-offs among multiple levels of SWC attributes, including households' SWC decision-making and physical and structural measures. The results from MNL regression show that both males and females exhibit positive preferences for multiple levels of SWC attributes, but show negative preferences when it comes to household decisions involving multiple SWC strategies. The study highlights the importance of equal opportunities for males and females' participation in agricultural transformation through the adoption of SWC technologies as a fundamental step towards sustainable agricultural intensification. It advocates for gender transformational approaches to incentivize the scaling up of SWC practices and promote packages with lower uptake rates. Additionally, the study suggests enhancing knowledge and extension education in SWC to better understand diverse needs and preferences of female farmers.

Comparing Discrete Choice Experiment with Swing Weighting to Estimate Attribute Relative Importance: A Case Study in Lung Cancer Patient Preferences

INTRODUCTION

Discrete choice experiments (DCE) are commonly used to elicit patient preferences and to determine the relative importance of attributes but can be complex and costly to administer. Simpler methods that measure relative importance exist, such as swing weighting with direct rating (SW-DR), but there is little empirical evidence comparing the two. This study aimed to directly compare attribute relative importance rankings and weights elicited using a DCE and SW-DR.

METHODS

A total of 307 patients with non-small-cell lung cancer in Italy and Belgium completed an online survey assessing preferences for cancer treatment using DCE and SW-DR. The relative importance of the attributes was determined using a random parameter logit model for the DCE and rank order centroid method (ROC) for SW-DR. Differences in relative importance ranking and weights between the methods were assessed using Cohen's weighted kappa and Dirichlet regression. Feedback on ease of understanding and answering the 2 tasks was also collected.

RESULTS

Most respondents (>65%) found both tasks (very) easy to understand and answer. The same attribute, survival, was ranked most important irrespective of the methods applied. The overall ranking of the attributes on an aggregate level differed significantly between DCE and SW-ROC (P < 0.01). Greater differences in attribute weights between attributes were reported in DCE compared with SW-DR (P < 0.01). Agreement between the individual-level attribute ranking across methods was moderate (weighted Kappa 0.53-0.55).

CONCLUSION

Significant differences in attribute importance between DCE and SW-DR were found. Respondents reported both methods being relatively easy to understand and answer. Further studies confirming these findings are warranted. Such studies will help to provide accurate guidance for methods selection when studying relative attribute importance across a wide array of preference-relevant decisions.

HIGHLIGHTS

Both DCEs and SW tasks can be used to determine attribute relative importance rankings and weights; however, little evidence exists empirically comparing these methods in terms of outcomes or respondent usability.Most respondents found the DCE and SW tasks very easy or easy to understand and answer.A direct comparison of DCE and SW found significant differences in attribute importance rankings and weights as well as a greater spread in the DCE-derived attribute relative importance weights.

Eliciting preferences for cancer screening tests: Comparison of a discrete choice experiment and the threshold technique

OBJECTIVE

To compare results of three preference elicitation methods for a cancer screening test.

METHODS

Participants (undergraduate students) completed a discrete choice experiment (DCE) and a threshold technique (TT) task. Accuracy (false positives, false negatives), benefits (lives saved), and cost for a cancer screening test were used as attributes in the DCE and branching logic for the TT. Participants were also asked a direct elicitation question regarding a hypothetical screening test for breast (women) or prostate (men) cancer without mortality benefit. Correlations assessed the relationship between DCE and TT thresholds. Thresholds were standardized and ranked for both methods to compare. A logistic regression used the thresholds to predict results of the direct elicitation.

RESULTS

DCE and TT estimates were not meaningfully correlated (max ρ = 0.17). Participant rankings of attributes matched only 20% of the time (58/292). Neither method predicted preference for being screened (ps > 0.21).

CONCLUSIONS

The DCE and TT yielded different preference estimates (and rank orderings) for the same participant. Neither method predicted patients' desires for a screening test.

PRACTICE IMPLICATIONS

Clinicians, patients, policy makers, and researchers should be aware that patient preference results may be sensitive to the method of eliciting preferences.