US Valuation of the EQ-5D Health States: Development and Testing of the D1 Valuation Model
ABSTRACT The EQ-5D is a brief, multiattribute, preference-based health status measure. This article describes the development of a statistical model for generating US population-based EQ-5D preference weights.
A multistage probability sample was selected from the US adult civilian noninstitutional population. Respondents valued 13 of 243 EQ-5D health states using the time trade-off (TTO) method. Data for 12 states were used in econometric modeling. The TTO valuations were linearly transformed to lie on the interval [-1, 1]. Methods were investigated to account for interaction effects caused by having problems in multiple EQ-5D dimensions. Several alternative model specifications (eg, pooled least squares, random effects) also were considered. A modified split-sample approach was used to evaluate the predictive accuracy of the models. All statistical analyses took into account the clustering and disproportionate selection probabilities inherent in our sampling design.
Our D1 model for the EQ-5D included ordinal terms to capture the effect of departures from perfect health as well as interaction effects. A random effects specification of the D1 model yielded a good fit for the observed TTO data, with an overall R of 0.38, a mean absolute error of 0.025, and 7 prediction errors exceeding 0.05 in absolute magnitude.
The D1 model best predicts the values for observed health states. The resulting preference weight estimates represent a significant enhancement of the EQ-5D's utility for health status assessment and economic analysis in the US.
- SourceAvailable from: Stein Jasper Janssen
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- "We used the English version for the United States with three answer options for every question (EQ-5D 3L) . An overall EQ-5D index for those who completed all five questions (n=77) was calculated using an algorithm described by Shaw et al. . The EQ-5D index score ranges from 0 to 1, with a higher score indicating better quality of life. "
ABSTRACT: General questionnaires are often used to assess quality of life in patients with spine metastases, while a disease-specific survey did not exist until recently. The Spine Oncology Study Group has developed a questionnaire (SOSG-OQ) to measure quality of life in these patients. However, a scoring system was not developed and the questionnaire was not validated in a group of patients, nor was it compared to other general quality of life questionnaires such as the EuroQol 5 Dimensions (EQ-5D) questionnaire. Our primary null hypothesis is that there is no association between the SOSG-OQ and EQ-5D. Our secondary null hypothesis is that there is no difference in coverage and internal consistency between the SOSG-OQ and EQ-5D. We also assess coverage, consistency, and validity of the domains within the SOSG-OQ. Survey study from a tertiary care spine referral center. 82 patients with spine metastases, myeloma, or lymphoma. The SOSG-OQ (27 questions, 6 domains) score ranges from 0 to 80 with a higher score indicating worse quality of life. The EQ-5D (5 questions, 5 domains) index score ranges from 0 to 1 with a higher score indicating better quality of life. The association between the SOSG-OQ and EQ-5D index score was assessed using the Spearman rank correlation. Instrument coverage and precision were assessed by determining item completion rate, median score with range, and floor and ceiling effect. Internal consistency was assessed using Cronbach alpha. Multitrait analysis and exploratory factor analysis were used to analyze properties of the individual domains in the SOSG-OQ. No grants or funds were received for this study. The Spearman rank correlation between the SOSG-OQ and EQ-5D questionnaire was high (r = -0.83, P < 0.001). Internal consistency of the SOSG-OQ (0.92, 95% CI: 0.89 - 0.94) was higher as compared to the internal consistency of the EQ-5D (0.73, 95% CI: 0.63 - 0.84; P < 0.001). The SOSG-OQ score had no floor or ceiling effect indicating good coverage (median 30, range 3 - 64), while the EQ-5D had a ceiling effect of 10% (median 0.71, range 0.05 - 1). In conclusion, our study proposes a scoring methodology -after reversing 4 inversely scored items- for the SOSG-OQ and demonstrates that the questionnaire is a valid tool for the assessment of quality of life in patients with metastatic spine disease. The SOSG-OQ is superior to the EQ-5D in terms of coverage and internal consistency, but consists of more questions. Copyright © 2015. Published by Elsevier Inc.The spine journal: official journal of the North American Spine Society 08/2015; DOI:10.1016/j.spinee.2015.07.456 · 2.43 Impact Factor
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- "Several utility tariffs have been developed on the basis of stated health preferences of respondents from different countries including the United Kingdom , Japan , Korea , New Zealand , the United States , and Malaysia . When local tariffs are not available, studies have applied utility tariffs from other countries, such as the UK population tariff or others . "
ABSTRACT: Objectives: This study's objectives were to estimate the quality of life (QOL) of Malaysian patients with acute coronary syndrome (ACS) during admission and at 12 months, to explore the factors associated with the QOL, and to compare utility scores derived from tariffs from local and foreign populations. Methods: Data collected from patients with ACS between 2008 and 2009 for a study on cardiac rehabilitation at the Sarawak General Hospital were used for this study. QOL data were obtained using a validated version of the EuroQol five-dimensional questionnaire at baseline and at 12 months. Health utility scores were calculated using visual analogue scale scores and utility tariffs from Malaysia and the United Kingdom. Results: Data from 104 subjects from the earlier study was used. The mean age was 56.1 years, with 88.5% being men. The mean hospitalization duration was 6.3 days. The mean utility score was 0.75 at baseline and 0.82 at 12 months. There was a statistically significant improvement in utility from baseline to 12 months based on the Malaysian tariff (P = 0.014) but not with the UK tariff (P = 0.086). The QOL of patients was associated with sex and diagnosis of ST-segment elevation myocardial infarction. Conclusions: Our results showed that there was a significant improvement in the QOL from baseline to 12 months. Only sex and diagnosis affected the QOL score at baseline because of limited variables available for testing. It also reconfirms the importance of applying the appropriate, country-specific utility tariffs in QOL studies. Despite limitations, the study is useful toward describing QOL among a group of Malaysian patients with ACS. © 2015 International Society for Pharmacoeconomics and Outcomes Research (ISPOR).05/2015; 6:80-83. DOI:10.1016/j.vhri.2015.03.015
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- "Additionally, data from a visual analogue scale, which ranges from 0 (worst imaginable health) to 100 (best imaginable health), are also included as part of the EQ-5D measure. The current study used the norms and time tradeoff valuations developed for the U.S. population (Shaw et al., 2005). "
ABSTRACT: Building upon recommendations to broaden the conceptualization of recovery and to assess its relationship with health-related quality of life (HRQoL), this study addressed three primary aims. These included: 1) Testing the model fit of a hypothesized latent measure of recovery, 2) Examining the extent to which this multidimensional measure of recovery was associated with concurrently measured HRQoL, and 3) Examining the extent to which this multidimensional measure of recovery predicted changes in HRQoL during the subsequent year. Data were from 1,008 adults who completed follow-up assessments at 15 and 16 years post-intake. Confirmatory factor analysis indicated a good fit for a hypothesized recovery measure (CFI = .98; RMSEA = .06). Additionally, structural equation modeling suggested that this recovery measure was not only concurrently associated with HRQoL (β = .78, p < .001), but was also a significant predictor of changes in HRQoL during the subsequent year (β = .25, p < .001).Journal of Substance Abuse Treatment 10/2014; 47(4). DOI:10.1016/j.jsat.2014.05.006 · 3.14 Impact Factor