Test-Retest Reliability of Discrete Choice Experiment for Valuations of QLU-C10D Health States

Evaluation of measurement properties of the Impact of Weight on Quality of Life-Lite (IWQOL-Lite) instrument among Chinese overweight and obese populations

PURPOSE

To evaluate measurement properties of the Impact of Weight on Quality of Life-Lite (IWQOL-Lite) instrument among Chinese overweight and obese populations.

METHODS

A representative sample of Chinese overweight and obese populations was recruited stratified by age, sex, residence and body mass index (BMI). Social-demographic characteristics, self-reported EQ-5D-5 L and IWQOL-Lite responses were collected through the online survey. Test-retest reliability was assessed using intraclass correlation coefficient (ICC) among a subgroup of the total sample. Structural validity was evaluated by confirmatory factor analysis (CFA). Convergent validity and known-group validity were examined using Spearman's rank correlation and effect sizes, respectively.

RESULTS

A total of 1000 respondents (48% female; mean age: 51.7 years; mean BMI: 27.4) were included in this study. Ceiling and floor effects of the IWQOL-Lite were 5.4% and 0.67%, respectively. The ICC between the two tests was 0.992 for IWQOL-Lite among the subgroup (N = 150). The results of the CFA suggested that the five-factor model had an acceptable structural validity (GFI = 0.894, CFI = 0.960, TLI = 0.957, RMSEA = 0.054 and SRMR = 0.033). The Spearman's rank correlation (range: 0.413-0.611) indicated a satisfactory convergent validity. The effect sizes values of IWQOL-Lite total score and different dimensions were moderate.

CONCLUSIONS

The IWQOL-Lite has been demonstrated to have satisfactory validity and reliability in measuring the HRQoL of Chinese overweight and obese populations. Further research is needed to confirm the sensitivity and responsiveness.

Norwegian and Swedish value sets for the EORTC QLU-C10D utility instrument

PURPOSE

This study aimed to develop utility weights for the European Organization for Research and Treatment of Cancer (EORTC) QLU-C10D, a cancer-specific utility instrument, tailored to the Norwegian and Swedish populations. The utility weights are intended for use in the specific welfare contexts of Norway and Sweden to support more precise healthcare decision-making in cancer treatment and care.

METHODS

This cross-sectional study included 1019 Norwegian and 1048 Swedish participants representative in age and gender of the two general populations. Participants completed a discrete choice experiment involving 960 choice sets, each consisting of two EORTC QLU-C10D health states described by the instrument's domains and the duration of each state. Utility weights were calculated using generalized estimation equation models, and non-monotonic levels were merged to ensure consistent valuation.

RESULTS

In the Norwegian participants, the largest utility decrements were seen for the domain of physical functioning (decrement of - 0.263 for highest level "very much"), followed by pain (decrement - 0.205 for level "very much") and role functioning (- 0.139). Among the cancer-specific domains, nausea had the largest utility decrement (- 0.124). In the Swedish participants, the largest utility decrements were also observed for physical functioning (- 0.207 for the response "very much"), followed by pain (- 0.139), role functioning (- 0.133), and nausea (- 0.119). Emotional functioning also exhibited a sizable utility decrement (- 0.115).

CONCLUSION

This study provides the first set of utility weights for the EORTC QLU-C10D specific to Norway and Sweden, reflecting the unique health preferences of these populations. The generated utility decrements can inform cost-utility analyses and optimize resource allocation in cancer care within the Norwegian and Swedish healthcare systems.

Quantification of facial symmetry in orthognathic surgery: A novel approach integrating 3D contour maps and hyper-dimensional computing

This study aimed to enhance the evaluation of facial symmetry crucial for planning and assessing outcomes of orthognathic surgery (OGS). An innovative approach combining three-dimensional (3D) facial contour lines with hyperdimensional (HD) computing was developed for this purpose. Data were collected using 3D cone beam computed tomography (CBCT) at Chang Gung Memorial Hospital from 2016 to 2021. A comprehensive dataset was compiled, including images from 150 normal individuals and 2500 patients, totaling 5150 preoperative and postoperative facial images. A machine learning model was trained to analyze these images, and 3D contour data were used to create a facial symmetry quantification system with HD computing. Additionally, 3D CBCT data from 200 patients before and after OGS were retrospectively reviewed for clinical application. The developed facial symmetry algorithm demonstrated an overall accuracy of 84.1 %. Postoperative facial symmetry scores improved significantly, with a mean score increase of 53 %, from 2.40 to 3.63. The study culminated in the creation of a web-based system that leverages HD computing and 3D contour mapping to automate facial symmetry assessment. This system offers a user-friendly interface for rapid and accurate evaluations, facilitating better communication between clinicians and patients.

Chinese utility weights for the EORTC cancer-specific utility instrument QLU-C10D

OBJECTIVE

The aim of this study is to provide Chinese utility weights for the European Organization for Research and Treatment of Cancer Quality of Life Utility Measure-Core 10 Dimensions (EORTC QLU-C10D) which is a preference-based cancer-specific utility instrument derived from the EORTC QLQ-C30.

METHODS

We conducted an online survey of the general population in China, with quota sampling for age and gender. Each respondent was asked to complete a discrete choice experimental survey consisting of 16 randomly selected choice sets. The conditional logit model and mixed logit model were used to analyze respondents' preferences, and the goodness of fit of the model was tested.

RESULTS

A total of 2003 respondents were included in the analysis. Utility decrements within dimensions were typically monotonic. Monotonic inconsistency issues in the Fatigue, Sleep, and Nausea dimensions were normalized by monotonicity correction. Physical functioning, Pain, and Role functioning were associated with the greatest utility weights, with the smallest decrements being in Bowel problems and Emotional functioning. The utility value for the worst health state was 0.083, i.e. slightly higher than being dead.

CONCLUSIONS

This study provides the first China-specific set of value for the QLU-C10D based on societal preferences of the Chinese adult general population. The value set can be used as a cancer-specific scoring system for economic evaluations of new oncology therapies and technologies in China.

A scoping review to create a framework for the steps in developing condition-specific preference-based instruments de novo or from an existing non-preference-based instrument: use of item response theory or Rasch analysis

BACKGROUND

There is no widely accepted framework to guide the development of condition-specific preference-based instruments (CSPBIs) that includes both de novo and from existing non-preference-based instruments. The purpose of this study was to address this gap by reviewing the published literature on CSPBIs, with particular attention to the application of item response theory (IRT) and Rasch analysis in their development.

METHODS

A scoping review of the literature covering the concepts of all phases of CSPBI development and evaluation was performed from MEDLINE, Embase, PsychInfo, CINAHL, and the Cochrane Library, from inception to December 30, 2022.

RESULTS

The titles and abstracts of 1,967 unique references were reviewed. After retrieving and reviewing 154 full-text articles, data were extracted from 109 articles, representing 41 CSPBIs covering 21 diseases or conditions. The development of CSPBIs was conceptualized as a 15-step framework, covering four phases: 1) develop initial questionnaire items (when no suitable non-preference-based instrument exists), 2) establish the dimensional structure, 3) reduce items per dimension, 4) value and model health state utilities. Thirty-nine instruments used a type of Rasch model and two instruments used IRT models in phase 3.

CONCLUSION

We present an expanded framework that outlines the development of CSPBIs, both from existing non-preference-based instruments and de novo when no suitable non-preference-based instrument exists, using IRT and Rasch analysis. For items that fit the Rasch model, developers selected one item per dimension and explored item response level reduction. This framework will guide researchers who are developing or assessing CSPBIs.

Danish value sets for the EORTC QLU-C10D utility instrument

PURPOSE

In this study, we developed Danish utility weights for the European Organisation for Research and Treatment of Cancer (EORTC) QLU-C10D, a cancer-specific utility instrument based on the EORTC QLQ-C30.

METHODS

Following a standardized methodology, 1001 adult participants from the Danish general population were quota-sampled and completed a cross-sectional web-based survey and discrete choice experiment (DCE). In the DCE, participants considered 16 choice sets constructed from the key 10 dimensions of the QLU-C10D and chose their preferred health state for each one. Utility weights were calculated using conditional logistic regression with correction for non-monotonicity.

RESULTS

The sample (n = 1001) was representative of the Danish general population with regard to age and gender. The domains with the largest utility decrements, i.e., the domains with the biggest impact on health utility, were physical functioning (- 0.224), pain (- 0.160), and role functioning (- 0.136). The smallest utility decrements were observed for the domains lack of appetite (- 0.024), sleep disorders (- 0.057), and fatigue (- 0.064). Non-monotonicity of severity levels was observed for the domains sleep disturbances, lack of appetite, and bowel problems. Deviations from monotonicity were not statistically significant.

CONCLUSION

The EORTC QLU-C10D is a relatively new multi-attribute utility instrument and is a promising cancer-specific health technology assessment candidate measure. The country-specific Danish utility weights from this study can be used for cost-utility analyses in Danish patients and for comparison with other country-specific utility data.

Comparative performance and mapping algorithms between EQ-5D-5L and SF-6Dv2 among the Chinese general population

OBJECTIVES

To explore the comparative performance and develop the mapping algorithms between EQ-5D-5L and SF-6Dv2 in China.

METHODS

Respondents recruited from the Chinese general population completed both EQ-5D-5L and SF-6Dv2 during face-to-face interviews. Ceiling/floor effects were reported. Discriminative validity in self-reported chronic conditions was investigated using the effect sizes (ES). Test-retest reliability was evaluated using intra-class correlation coefficient (ICC) and Bland-Altman plots in a subsample. Correlation and absolute agreements between the two measures were estimated with Spearman's rank correlation coefficient and ICC, respectively. Ordinary least squares (OLS), generalized linear model, Tobit model, and robust MM-estimator were explored to estimate mapping equations between EQ-5D-5L and SF-6Dv2.

RESULTS

3320 respondents (50.3% males; age 18-90 years) were recruited. 51.1% and 12.2% of respondents reported no problems on all EQ-5D-5L and SF-6Dv2 dimensions, respectively. The mean EQ-5D-5L utility was higher than SF-6Dv2 (0.947 vs. 0.827, p < 0.001). Utilities were significantly different across all chronic conditions groups for both measures. The mean absolute difference of utilities between the two tests for EQ-5D-5L was smaller (0.033 vs. 0.043) than SF-6Dv2, with a slightly higher ICC (0.859 vs. 0.827). Fair agreement (ICC = 0.582) was observed in the utilities between the two measures. Mapping algorithms generated by the OLS models performed the best according to the goodness-of-fit indicators.

CONCLUSIONS

Both measures showed comparable discriminative validity. Systematic differences in utilities were found, and on average, the EQ-5D-5L generates higher values than the SF-6Dv2. Mapping algorithms between the EQ-5D-5L and SF-6Dv2 are reported to enable transformations between these two measures in China.

Comparison of the measurement properties of the EQ-5D-5L and SF-6Dv2 among overweight and obesity populations in China

OBJECTIVE

To evaluate and compare the measurement properties of the EQ-5D-5L and SF-6Dv2 among Chinese overweight and obesity populations.

METHODS

A representative sample of Chinese overweight and obesity populations was recruited stratified by age, gender, body mass index (BMI), and area of residence. Social-demographic characteristics and self-reported EQ-5D-5L and SF-6Dv2 responses were collected through the online survey. The agreement was assessed using intraclass correlation coefficients (ICC). Convergent validity and known-group validity were examined using Spearman's rank correlation and effect sizes, respectively. The test-retest reliability was assessed using among a subgroup of the total sample. Sensitivity was compared using relative efficiency and receiver operating characteristic.

RESULTS

A total of 1000 respondents (52.0% male, mean age 51.7 years, 67.7% overweight, 32.3% obesity) were included in this study. A higher ceiling effect was observed in EQ-5D-5L than in SF-6Dv2 (30.6% vs. 2.1%). The mean (SD) utility was 0.851 (0.195) for EQ-5D-5L and 0.734 (0.164) for SF-6Dv2, with the ICC of the total sample was 0.639 (p < 0.001). The Spearman's rank correlation (range: 0.186-0.739) indicated an acceptable convergent validity between the dimensions of EQ-5D-5L and SF-6Dv2. The EQ-5D-5L showed basically equivalent discriminative capacities with the SF-6Dv2 (ES: 0.517-1.885 vs. 0.383-2.329). The ICC between the two tests were 0.939 for EQ-5D-5L and 0.972 for SF-6Dv2 among the subgroup (N = 150). The SF-6Dv2 had 3.7-170.1% higher efficiency than the EQ-5D-5L at detecting differences in self-reported health status, while the EQ-5D-5L was found to be 16.4% more efficient at distinguishing between respondents with diabetes and non-diabetes.

CONCLUSIONS

Both the EQ-5D-5L and SF-6Dv2 showed comparable reliability, validity, and sensitivity when used in Chinese overweight and obesity populations. The two measures may not be interchangeable given the systematic difference in utility values between the EQ-5D-5L and SF-6Dv2. More research is needed to compare the responsiveness.

Stability of Stated Preferences: Vaccine Priority Setting before and during the First COVID-19 Lockdown

BACKGROUND

Discrete choice experiments (DCEs) are frequently used to study preferences and quantify tradeoffs in decision making. It is important to understand how stable their results are.

OBJECTIVE

To investigate to what extent an extreme change in context, the COVID-19 pandemic, affected preferences for vaccine priority setting, as observed in an earlier DCE.

METHODS

We replicated a DCE in which participants had to prioritize vaccination programs for public funding. The initial DCE was executed in Flanders (Belgium) right before the onset of the SARS-CoV-2 pandemic (December 2019, N = 1,636). The replicated DCE was executed 6 months later when the population was in lockdown (April 2020, N = 1,127). A total of 612 respondents participated in both waves of the DCE. We used panel mixed logit models to quantify attribute and level importance and compared utility estimates for consistency.

RESULTS

The number of vaccine-preventable deaths became less important during the pandemic than before, whereas the influential attributes, the vaccine's contribution to disease eradication and certainty about vaccine effectiveness became even more important. Respondents attached equal importance to the number of patients with transient or permanent morbidity, to the disease's economic impact as well as to its equity profile.

CONCLUSION

Different preferences for vaccine priority setting were observed during the first COVID-19 lockdown as compared with before, although these differences were, given the extreme nature of the changing circumstances, relatively small.

HIGHLIGHTS

We replicated a discrete choice experiment (DCE) about vaccine priority setting during the first COVID-19 lockdown and compared results with those from the original setting.The major attributes, contribution to disease eradication, and scientific certainty about vaccine effectiveness became even more important than they already were, whereas avoidable mortality became less important.Respondents attached equal importance to the number of patients with transient or permanent morbidity, to the disease's economic impact as well as to its equity profile.An extreme change in directly related context to the choice assignment led to changes in stated preferences, although these changes were relatively small, given the extreme change in context.Priorities in the second DCE were even less aligned with cost-effectiveness analysis than those observed initially.

Test-Retest Reliability of EQ-5D-Y-3L Best-Worst Scaling Choices of Adolescents and Adults

BACKGROUND

There is an increasing interest to obtain adolescents' own health state valuation preferences and to understand how these differ from adult preferences for the same health state. An important question in health state valuation is whether adolescents can report preferences reliably, yet research remains limited.

OBJECTIVE

This study aims to investigate the test-retest reliability of best-worst scaling (BWS) to elicit adolescent preferences compared with adults.

METHODS

Identical BWS tasks designed to value 3-level version of EQ-5D-Y health states were administered online in samples of 1000 adolescents (aged 11-17 years) and 1006 adults in Spain. The valuation survey was repeated approximately 3 days later. We calculated (1) simple percentage agreement and (2) kappa statistic as measures of test-retest reliability. We also compared BWS marginal frequencies and relative attribute importance between baseline and follow-up to explore similarities in the obtained preferences.

RESULTS

We found that both adolescents and adults were able to report their preferences with moderate reliability (kappa: 0.46 for adolescents, 0.46 for adults) for best choices and fair to moderate reliability (kappa: 0.39 for adolescents, 0.41 for adults) for worst choices. No notable difference was observed across years of child age. Higher consistency was observed for best choices than worst in some dimensions for both populations. No significant differences were found in the relative attribute importance between baseline and follow-up in both populations.

CONCLUSION

Our results suggest that BWS is a reliable elicitation technique to value 3-level version of EQ-5D-Y health states in both adolescents and adults.

Does Changing the Age of a Child to be Considered in 3-Level Version of EQ-5D-Y Discrete Choice Experiment-Based Valuation Studies Affect Health Preferences?

OBJECTIVES

There has been some debate about the choice of perspective and the age of the child considered when completing preference elicitation tasks in the 3-level version of EQ-5D-Y (EQ-5D-Y-3L) valuation protocol. This study aimed to clarify the impact on latent scale EQ-5D-Y-3L values of varying the age of the child experiencing the health state considered by respondents completing the discrete choice experiment (DCE) tasks of the protocol.

METHODS

We conducted an online DCE with a representative sample of 1000 adults in the United Kingdom and 1000 adults in the United States. Respondents selected the health state they prefer from a series of DCE paired EQ-5D-Y-3L health state comparisons using their own perspective and that of a hypothetical child from the following age groups: "5-7 years old," "8-10 years old," "11-13 years old," and "14-15 years old." Data analysis was conducted using separate multinomial logit models for each perspective and country. We also estimated combined models including data from each possible pair of perspectives and used interactions between EQ-5D-Y-3L levels and perspective to determine whether any differences were statistically significant.

RESULTS

No statistically significant differences in coefficients between perspectives were found in the United States. In the United Kingdom, there were differences between the own perspective and the 5 to 7 years old perspective (looking after myself level 3) and between the 5 to 7 years old perspective and the 8 to 10 years old perspective (usual activities level 3).

CONCLUSIONS

Our results suggest that there is minimal impact on latent scale values when using different ages of the hypothetical child in the current EQ-5D-Y-3L valuation protocol.

Discrete choice experiment with duration versus time trade-off: a comparison of test-retest reliability of health utility elicitation approaches in SF-6Dv2 valuation

OBJECTIVES

To evaluate and compare the test-retest reliability of discrete choice experiments with duration (DCE_TTO) and time trade-off (TTO) in the Chinese SF-6Dv2 valuation study.

METHODS

During face-to-face interviews, a representative sample of the Chinese general population completed 8 TTO tasks and 10 DCE_TTO tasks. Retest interviews were conducted after two weeks. For both DCE_TTO and TTO, the consistency of raw responses between the two tests was firstly evaluated at the individual level. Regressions were conducted to investigate the association between the test-retest reliability and the respondents' characteristics and the severity of health states. Consistency was then analyzed at the aggregate level by comparing the rank order of the coefficients of dimensions.

RESULTS

In total, 162 respondents (51.9% male; range 18-80 years) completed the two tests. The intraclass correlations coefficient 0.958 for TTO, with identical values accounting for 59.3% of observations. 76.4% of choices were identical for DCE_TTO, with a Kappa statistic of 0.528. Respondents' characteristics had no significant impact while the severity of health states valued in TTO and DCE_TTO tasks had a significant impact on the test-retest reliability. Both approaches produced relatively stable rank order of dimensions in constrained model estimations between test and retest data.

CONCLUSIONS

Individual responses of both approaches are relatively stable over time. The rank orders of dimensions in model estimations between test and retest for TTO and DCE_TTO are also consistent. The differences of utility estimation between the two tests for DCE_TTO need to be further investigated based on a larger sample size.

The EORTC QLU-C10D discrete choice experiment for cancer patients: a first step towards patient utility weights

Background

The European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Utility-Core 10 Dimensions (QLU-C10D) is a novel cancer-specific preference-based measure (PBM) for which value sets are being developed for an increasing number of countries. This is done by obtaining health preferences from the respective general population. There is an ongoing discussion if instead patients suffering from the disease in question should be asked for their preferences. We used the QLU-C10D valuation survey, originally designed for use in the general population, in a sample of cancer patients in Austria to assess the methodology’s acceptability and applicability in this target group before obtaining QLU-C10D patient preferences.

Methods

The core of the QLU-C10D valuation survey is a discrete choice experiment in which respondents are asked to give preferences for certain health states (described by a relatively large number of 10 quality of life domains) and an associated survival time. They therewith are asked to trade off quality of life against life time. As this might be a very burdensome task for cancer patients undergoing treatment, a cognitive interview was conducted in a pilot sample to assess burden and potential additional needs for explanation in order to be able to use the DCE for the development of QLU-C10D patient preferences. In addition, responses to general feedback questions on the survey were compared against responses from a matched control group from the already completed Austrian general population valuation survey.

Results

We included 48 patients (mean age 59.9 years; 46% female). In the cognitive interview, the majority indicated that their experience with the survey was positive (85%) and overall clarity as good (90%). In response to the general feedback questions, patients rated the presentation of the health states less clear than matched controls (p = 0.008). There was no difference between patients and the general population concerning the difficulty in choosing between the health states (p = 0.344).

Conclusion

Despite the relatively large number of DCE domains the survey was manageable for patients and allows going on with the QLU-C10D patient valuation study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41687-022-00430-5.

Patterns of SARS-CoV-2 Testing Preferences in a National Cohort in the United States: Latent Class Analysis of a Discrete Choice Experiment

BACKGROUND

Inadequate screening and diagnostic testing in the United States throughout the first several months of the COVID-19 pandemic led to undetected cases transmitting disease in the community and an underestimation of cases. Though testing supply has increased, maintaining testing uptake remains a public health priority in the efforts to control community transmission considering the availability of vaccinations and threats from variants.

OBJECTIVE

This study aimed to identify patterns of preferences for SARS-CoV-2 screening and diagnostic testing prior to widespread vaccine availability and uptake.

METHODS

We conducted a discrete choice experiment (DCE) among participants in the national, prospective CHASING COVID (Communities, Households, and SARS-CoV-2 Epidemiology) Cohort Study from July 30 to September 8, 2020. The DCE elicited preferences for SARS-CoV-2 test type, specimen type, testing venue, and result turnaround time. We used latent class multinomial logit to identify distinct patterns of preferences related to testing as measured by attribute-level part-worth utilities and conducted a simulation based on the utility estimates to predict testing uptake if additional testing scenarios were offered.

RESULTS

Of the 5098 invited cohort participants, 4793 (94.0%) completed the DCE. Five distinct patterns of SARS-CoV-2 testing emerged. Noninvasive home testers (n=920, 19.2% of participants) were most influenced by specimen type and favored less invasive specimen collection methods, with saliva being most preferred; this group was the least likely to opt out of testing. Fast-track testers (n=1235, 25.8%) were most influenced by result turnaround time and favored immediate and same-day turnaround time. Among dual testers (n=889, 18.5%), test type was the most important attribute, and preference was given to both antibody and viral tests. Noninvasive dual testers (n=1578, 32.9%) were most strongly influenced by specimen type and test type, preferring saliva and cheek swab specimens and both antibody and viral tests. Among hesitant home testers (n=171, 3.6%), the venue was the most important attribute; notably, this group was the most likely to opt out of testing. In addition to variability in preferences for testing features, heterogeneity was observed in the distribution of certain demographic characteristics (age, race/ethnicity, education, and employment), history of SARS-CoV-2 testing, COVID-19 diagnosis, and concern about the pandemic. Simulation models predicted that testing uptake would increase from 81.6% (with a status quo scenario of polymerase chain reaction by nasal swab in a provider's office and a turnaround time of several days) to 98.1% by offering additional scenarios using less invasive specimens, both viral and antibody tests from a single specimen, faster turnaround time, and at-home testing.

CONCLUSIONS

We identified substantial differences in preferences for SARS-CoV-2 testing and found that offering additional testing options would likely increase testing uptake in line with public health goals. Additional studies may be warranted to understand if preferences for testing have changed since the availability and widespread uptake of vaccines.

The EORTC QLU-C10D was more efficient in detecting clinical known group differences in myelodysplastic syndromes than the EQ-5D-3L

BACKGROUND

The aim was to investigate the relative validity of the preference-based measure EORTC QLU-C10D in comparison with the EQ-5D-3L in myelodysplastic syndromes (MDS) patients.

METHODS

We used data from an international multicentre, observational cohort study of MDS patients. Baseline EORTC QLU-C10D and EQ-5D-3L scores were used and index scores calculated for Italy, Australia, and the UK. Criterion validity was established by Spearman and intraclass correlations (ICC) and Bland-Altman plots. Construct validity was established by the instruments' ability to discriminate known groups, i.e. groups whose health status is expected to differ.

RESULTS

We analyzed data from 619 MDS patients (61.1% male; median age 73.8 years). Correlations between theoretically corresponding domains were largely higher than between unrelated domains. ICCs and Bland-Altman plots indicated moderate to good criterion validity. Ceiling effects were lower for the QLU-C10D (4.7%) than for the EQ-5D-3L (22.6%). The EQ-5D-3L failed to discriminate known-groups in two and the QLU-C10D in one of the comparisons; the QLU-C10D's efficiency in doing so was higher in clinical known-groups. Results were comparable between the countries.

CONCLUSIONS

The QLU-C10D may be suitable to generate health utilities for economic research in MDS. Responsiveness and minimal important differences need yet to be established.

Patterns of SARS-CoV-2 testing preferences in a national cohort in the United States

In order to understand preferences about SARS-CoV-2 testing, we conducted a discrete choice experiment among 4793 participants in the Communities, Households, and SARS-CoV-2 Epidemiology (CHASING COVID) Cohort Study from July 30-September 8, 2020. We used latent class analysis to identify distinct patterns of preferences related to testing and conducted a simulation to predict testing uptake if additional testing scenarios were offered. Five distinct patterns of SARS-CoV-2 testing emerged. "Comprehensive testers" (18.9%) ranked specimen type as most important and favored less invasive specimen types, with saliva most preferred, and also ranked venue and result turnaround time as highly important, with preferences for home testing and fast result turnaround time. "Fast track testers" (26.0%) ranked result turnaround time as most important and favored immediate and same day turnaround time. "Dual testers" (18.5%) ranked test type as most important and preferred both antibody and viral tests. "Non-invasive dual testers" (33.0%) ranked specimen type and test type as similarly most important, preferring cheek swab specimen type and both antibody and viral tests. "Home testers" (3.6%) ranked venue as most important and favored home-based testing. By offering less invasive (saliva specimen type), dual testing (both viral and antibody tests), and at home testing scenarios in addition to standard testing scenarios, simulation models predicted that testing uptake would increase from 81.7% to 98.1%. We identified substantial differences in preferences for SARS-CoV-2 testing and found that offering additional testing options, which consider this heterogeneity, would likely increase testing uptake.

SIGNIFICANCE

During the COVID-19 pandemic, diagnostic testing has allowed for early detection of cases and implementation of measures to reduce community transmission of SARS-CoV-2 infection. Understanding individuals' preferences about testing and the service models that deliver tests are relevant in efforts to increase and sustain uptake of SARS-CoV-2 testing, which, despite vaccine availability, will be required for the foreseeable future. We identified substantial differences in preferences for SARS-CoV-2 testing in a discrete choice experiment among a large national cohort of adults in the US. Offering additional testing options that account for or anticipate this heterogeneity in preferences (e.g., both viral and antibody tests, at home testing), would likely increase testing uptake.

CLASSIFICATION

Biological Sciences (major); Psychological and Cognitive Sciences (minor).

Longitudinal Analysis of Quality-of-Life Recovery After Gastrectomy for Cancer

OBJECTIVE

The purpose of this study was to identify factors associated with quality-of-life recovery after gastrectomy.

METHODS

Patients anticipated to undergo gastric cancer resection were invited to complete the European Organisation for Research and Treatment of Cancer (EORTC) QLQ C30 and STO22 surveys in the preoperative setting and at 0-1.5 months (early), > 1.5-6 months (intermediate), and > 6-18 months (late) following resection. Quality-of-life recovery was measured as paired differences between pre- and postoperative results. Multivariable linear regression identified factors associated with preoperative quality of life and degree of change following resection.

RESULTS

Across 393 participants, response rates at the intermediate and late postoperative time points were 58% (n = 228) and 71% (n = 277), respectively. Relative to baseline, median global health scale decreased in the early (- 15.1 pts, p < 0.001) and intermediate (- 3.6 pts, p = 0.02) time points, but recovered by the late time point (+ 1.2 pts, p = 0.411). Relative to distal/subtotal gastrectomy, proximal/total gastrectomy was associated with worse recovery in both the early and late time points. Surgical complications were associated with worse early recovery. Patients who presented with locally advanced tumors (T3-T4) had lower preoperative quality-of-life scores, and more readily recovered to baseline after surgery. A minimally invasive approach was not associated with postoperative recovery.

CONCLUSIONS

Most patients recover to baseline within 1 year following major gastrectomy, and recovery is easier with more limited resections. Patients with locally advanced tumors tend to have poorer baseline quality of life, which may improve following resection.

Discrete choice experiments to generate utility values for multi-attribute utility instruments: a systematic review of methods

OBJECTIVES

In recent years, discrete choice experiments (DCEs) have become frequently used to generate utility values, but there are a diverse range of approaches to do this. The primary focus of this systematic review is to summarise the methods used for the design and analysis of DCEs when estimating utility values in both generic and condition-specific preference-based measures.

METHODS

Published literature using DCEs to estimate utility values from preference-based instruments were identified from MEDLINE, Embase, Cochrane Library and CINAHL using PRISMA guidelines. To assess the different DCE methods, standardised information was extracted from the articles including the DCE design method, the number of choice sets, the number of DCE pairs per person, randomisation of questions, analysis method, logical consistency tests and techniques for anchoring utilities. The CREATE checklist was used to assess the quality of the studies.

RESULTS

A total of 38 studies with samples from the general population, students and patients were included. Values for health states described using generic multi attribute instruments (MAUIs) (especially the EQ-5D) were the most commonly explored using DCEs. The studies showed considerable methodology and design diversity (number of alternatives, attributes, sample size, choice task presentation and analysis). Despite these differences, the quality of articles reporting the methods used for the DCE was generally high.

CONCLUSION

DCEs are an important approach to measure utility values for both generic and condition-specific instruments. However, a gold standard method cannot yet be recommended.

An Investigation of the Stability of Patients' Treatment Preferences Over the Course of a Clinical Trial

OBJECTIVES

The usefulness of discrete choice experiments (DCEs) to inform clinical guidelines rests on the assumption that patients facing the same treatment choice at different points in time will express the same preferences. This study provides the first investigation, to our knowledge, to specifically focus on the stability of patients' treatment preferences over the course of a clinical trial.

METHODS

The same DCE was completed by participants at baseline and final post-treatment assessment in a trial of the efficacy of alternative topical treatments for actinic keratosis as a means for the prevention of skin cancer. The study assesses both the consistency of stated treatment choices and the stability of population-level preference parameter estimates and analyzes how the former is influenced by design aspects of the DCE.

RESULTS

No evidence was found of population-level preference parameter instability over the course of the trial despite only a moderate strength of choice consistency. Choice consistency is negatively related to task difficulty with weak evidence of the existence of ordering effects over the sequence of choice tasks.

CONCLUSIONS

The results provide no evidence that the timing of a DCE within a clinical trial significantly influences population-level treatment preference estimates.

EORTC QLU-C10D value sets for Austria, Italy, and Poland

Objective

To develop Austrian, Italian, and Polish general population value sets for the EORTC QLU-C10D, a cancer-specific utility instrument based on the EORTC QLQ-C30, and to descriptively compare their index scores for distinct health states.

Methods

The QLU-C10D descriptive system comprises 10 health attributes and each can take on 4 levels. A standardised and pre-tested methodology has been applied for valuations including a web-based discrete choice experiment (DCE). It was administered in 1000 general population respondents per country recruited via online panels, aiming at representativeness for core socio-demographic variables.

Results

In all three countries, the attributes with the largest impact on utility were physical functioning, pain, and role functioning. Cancer-specific dimensions with the largest impact were nausea and fatigue or bowel problems. Utility values of the worst health state (i.e. severe problems on all 10 dimension) were -0.111 (Austria), 0.025 (Italy), and 0.048 (Poland). Country-specific utilities differed for a selection of health states across the continuum. Austrian utilities were systematically lower for moderately and severely impaired health states.

Conclusion

QLU-C10D cancer-specific utilities can now be calculated in three more countries. Differences between countries indicate that careful consideration is required when using non-country-specific value sets in economic evaluations.

Electronic supplementary material

The online version of this article (10.1007/s11136-020-02536-z) contains supplementary material, which is available to authorized users.

Sequence effects in time trade-off valuation of hypothetical health states

Choice-based stated preference methods, such as time trade-offs (TTOs), are used to establish health state utilities informing healthcare allocation. However, little is known about the presence of (position-dependent and precedent-dependent) sequence effects in the valuation of health states, despite techniques requiring respondents to evaluate several health states in a sequence. This paper is the first to explicitly test for the presence of sequence effects in the health domain using a new explanation based on contrast effects and preference imprecision; the implication being that randomisation cannot avoid sequence effects. Six TTO questions were designed using the EQ-5D-3L descriptive system. These were grouped into two blocks of three and within each block four sequences were used. In an online survey, 1,197 Spanish respondents answered one grouping of three TTO questions. Results indicate that sequence effects can affect preferences as utilities of health states are biased downwards if preceded by a better health state and biased upwards if preceded by a worse health state. This study informs our understanding of how context effects interact with preference elicitation methods, which is essential for interpreting survey results used to inform policy.

Health Technology Assessment Challenges in Oncology: 20 Years of Value in Health

BACKGROUND

Oncology treatments have changed from chemotherapies to targeted therapies and more recently immuno-oncology. This has posed special challenges in the field of health technology assessment (HTA): capturing quality of life (QOL) associated with toxicity due to chemotherapy, crossover upon progression in targeted therapy trials, and survival extrapolation for immuno-oncology drugs.

OBJECTIVES

To showcase 20 years of Value in Health (ViH) publications in oncology.

METHODS

A review was undertaken of oncology articles published in ViH from May 1998 to August 2018. Full-length articles published in ViH with the keywords "oncology," "cancer," "h(a)ematology," and "malignancy" were included for review. Conference abstracts were excluded.

RESULTS

Four major themes were identified: (1) QOL and the development of multiple functional assessment of cancer therapy tools and mapping instruments; (2) analysis of clinical evidence using indirect comparisons, network analyses, and adjustment for crossovers; (3) modeling, Markov models, partitioned survival models, and extrapolation methods; and (4) financial implications and how to deal with uncertainty, introduction of conditional reimbursement, managed entry, and risk share agreements.

DISCUSSION

This review article highlights the important role ViH has played in disseminating HTA research in oncology. A few key issues loom on the horizon: precision medicine, further development and practical application of new QOL measures, methods for translating clinical evidence, and exploration of modeling techniques. For a better understanding of the complex interplay between access and financial risk management, ViH will no doubt continue to promote pioneering research in HTA and oncology.

One Method, Many Methodological Choices: A Structured Review of Discrete-Choice Experiments for Health State Valuation

BACKGROUND

Discrete-choice experiments (DCEs) are used in the development of preference-based measure (PBM) value sets. There is considerable variation in the methodological approaches used to elicit preferences.

OBJECTIVE

Our objective was to carry out a structured review of DCE methods used for health state valuation.

METHODS

PubMed was searched until 31 May 2018 for published literature using DCEs for health state valuation. Search terms to describe DCEs, the process of valuation and preference-based instruments were developed. English language papers with any study population were included if they used DCEs to develop or directly inform the production of value sets for generic or condition-specific PBMs. Assessment of paper quality was guided by the recently developed Checklist for Reporting Valuation Studies. Data were extracted under six categories: general study information, choice task and study design, type of designed experiment, modelling and analysis methods, results and discussion.

RESULTS

The literature search identified 1132 published papers, and 63 papers were included in the review. Paper quality was generally high. The study design and choice task formats varied considerably, and a wide range of modelling methods were employed to estimate value sets.

CONCLUSIONS

This review of DCE methods used for developing value sets suggests some recurring limitations, areas of consensus and areas where further research is required. Methodological diversity means that the values should be seen as experimental, and users should understand the features of the value sets produced before applying them in decision making.