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Background: Despite evidence of nonproportional trade-offs in time trade-off exercises and the explicit incorporation of exponential discounting in health technology assessment calculations, quality-adjusted life-year (QALY) tariffs are currently still established under the assumption of linear time preferences., Objectives: The aim of this study was to introduce a general method of accommodating for nonlinear time preferences in discrete choice experiment (DCE) duration studies and to evaluate its impact on estimated QALY tariffs., Methods: A parsimonious utility function is proposed that accommodates any discounting function and preserves linear time preferences as a special case. Based on an efficient DCE design and 1775 respondents from a nationally representative scientific household panel, preferences and QALY tariffs for the Dutch SF-6D were estimated while accommodating for nonlinear time preferences via exponential and hyperbolic discounting functions., Results: When the discount rate was estimated directly, we found strong evidence of nonlinear time preferences (with an exponential and hyperbolic discount rate of 5.7% and 16.5%, respectively). When the discount rate was estimated as a function of health state severity, we found that years lived in better health states are discounted minus years lived in impaired health states. Finally, the best statistical fit was obtained when using a hyperbolic discount function, which resulted in smaller QALY decrements and fewer health states classified as worse than immediate death., Conclusions: Our results highlight the relevance and even necessity of a paradigm shift in health valuation studies in favor of time-preference corrected QALY tariffs, with potentially important implications for health technology assessment calculations and regulatory decisions., (Copyright © 2018 ISPOR–The Professional Society for Health Economics and Outcomes Research. Published by Elsevier Inc. All rights reserved.)

Objective: The aim of this study was to test the hypothesis that level overlap and color coding can mitigate or even preclude the occurrence of attribute nonattendance in discrete choice experiments., Methods: A randomized controlled experiment with five experimental study arms was designed to investigate the independent and combined impact of level overlap and color coding on respondents' attribute nonattendance. The systematic differences between the study arms allowed for a direct comparison of observed dropout rates and estimates of the average number of attributes attended to by respondents, which were obtained by using augmented mixed logit models that explicitly incorporated attribute non-attendance., Results: In the base-case study arm without level overlap or color coding, the observed dropout rate was 14%, and respondents attended, on average, only two out of five attributes. The independent introduction of both level overlap and color coding reduced the dropout rate to 10% and increased attribute attendance to three attributes. The combination of level overlap and color coding, however, was most effective: it reduced the dropout rate to 8% and improved attribute attendance to four out of five attributes. The latter essentially removes the need to explicitly accommodate for attribute non-attendance when analyzing the choice data., Conclusions: On the basis of the presented results, the use of level overlap and color coding are recommendable strategies to reduce the dropout rate and improve attribute attendance in discrete choice experiments., (Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.)

Objective: To identify which specifications and approaches to model selection better predict health preferences, the International Academy of Health Preference Research (IAHPR) hosted a predictive modeling competition including 18 teams from around the world., Methods: In April 2016, an exploratory survey was fielded: 4074 US respondents completed 20 out of 1560 paired comparisons by choosing between two health descriptions (e.g., longer life span vs. better health). The exploratory data were distributed to all teams. By July, eight teams had submitted their predictions for 1600 additional pairs and described their analytical approach. After these predictions had been posted online, a confirmatory survey was fielded (4148 additional respondents)., Results: The victorious team, "Discreetly Charming Econometricians," led by Michał Jakubczyk, achieved the smallest χ 2 , 4391.54 (a predefined criterion). Its primary scientific findings were that different models performed better with different pairs, that the value of life span is not constant proportional, and that logit models have poor predictive validity in health valuation., Conclusions: The results demonstrated the diversity and potential of new analytical approaches in health preference research and highlighted the importance of predictive validity in health valuation., (Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study is to compare the health-related quality of life (HrQoL) of preschool children who stutter (CWS) and a reference population of children who do not stutter, and to evaluate the association between stuttering severity and HrQoL., Methods: Baseline data were used from 197 children participating in a multicenter Randomized Clinical Trial in the Netherlands. Information on stuttering severity and time since onset (TSO) of stuttering was obtained from the baseline evaluation by speech- and language therapists. Stuttering severity was measured using the SSI-3. HrQoL was assessed using proxy versions of two Child Health Questionnaires (ITQOL-97 and CHQ-PF28), the Health Utility Index 3 (HUI3) and the EuroQoL EQ-VAS (EQ-VAS)., Results: While the outcomes on the EQ-VAS and the HUI3 showed that the HrQoL of CWS is slightly poorer than that of the Dutch reference population, results on the different dimensions of the CHQ-instruments did not reveal any difference in scores between stuttering children and reference groups. Within the group of CWS, two ITQOL-97 and four CHQ-PF28 scales showed statistically different scores for children in different SSI stuttering severity or TSO categories. However, the effect sizes showed that these differences were so small that they could be considered negligible., Conclusion: The results of this study do not reveal a diminished HrQoL for preschool CWS. Future research should include a larger cohort of children with severe stuttering, study the longitudinal course of HrQoL and incorporate additional parameters such as the characteristics of the child and his environment., Educational Objectives: The reader will be able to: (a) summarize the current evidence base on HrQoL in people who stutter; (b) describe the HrQoL of preschool CWS on different HrQoL measures; (c) describe the relationship between stuttering severity and HrQoL in preschool CWS., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objectives: Some argue that generic preference-based measures (PBMs) are not sensitive to certain disease-specific improvements. To overcome this problem, new condition-specific PBMs (CS-PBMs) are being developed, but it is not yet clear how such measures compare with existing generic PBMs., Method: We generated CS-PBMs from three condition-specific questionnaires (Health Assessment Questionnaire for arthritis, Quality of Life Questionnaire for Cancer 30 for cancer, and Multiple Sclerosis Impact Scale 29 for multiple sclerosis). First, the questionnaires were reduced in content, and then, a time trade-off study was conducted in the general public (N = 402) to obtain weights associated with the dimensions and levels of the new questionnaire. Finally, we compared utilities obtained by using the CS-PBMs with utilities obtained by using the EuroQol five-dimensional (EQ-5D) questionnaire in four data sets., Results: Utility values generated by the CS-PBMs were higher than those of the EQ-5D questionnaire. The Health Assessment Questionnaire-based measure for arthritis proved to be insensitive to comorbidities. Measures based on the Multiple Sclerosis Impact Scale 29 and the Quality of Life Questionnaire for Cancer 30 discriminated comorbidities and side effect equally well as the EQ-5D questionnaire and were more sensitive than the EQ-5D questionnaire for mild impairments., Conclusions: The introduction of PBMs that are specific to a certain disease may have the merit of sensitivity to disease-specific effects of interventions. That gain, however, is traded off to the loss of comparability of utility values and, in some cases, insensitivity to side effects and comorbidity. The use of a CS-PBM for cost-utility analysis is warranted only under strict conditions., (Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.)

Objectives: Probabilistic models have been developed to establish the relative merit of subjective phenomena by means of specific judgmental tasks involving discrete choices (DCs). The attractiveness of these DC models is that they are embedded in a strong theoretical measurement framework and are based on relatively simple judgmental tasks. The aim of our study was to determine whether the values derived from a DC experiment are comparable to those obtained using other valuation techniques, in particular the time trade-off (TTO)., Methods: Two hundred nine students completed several tasks in which we collected DC, rank, visual analog scale, and TTO responses. DC data were also collected in a general population sample (N=444). The DC experiment was designed using a Bayesian approach, and involved 60 choices between two health states and a comparison of all health states to being dead. The DC data were analyzed using a conditional logit and a rank-ordered logit model, relying, respectively, on TTO values and the value for being dead to anchor the DC-derived values to the 0 to 1 quality-adjusted life-year (QALY) scale., Results: Although modeled DC data broadly replicated the pattern found in TTO responses, the DC consistently produced higher values. The two methods for anchoring DC-derived values on the QALY scale produced similar results., Conclusions: On the basis of the high level of comparability between DC-derived values and TTO values, future valuation studies based on a combination of these two techniques may be considered. The results further suggest that DC can potentially be used as a substitute for TTO., (© 2010, International Society for Pharmacoeconomics and Outcomes Research (ISPOR).)