Mapping EQ-5D-3L to EQ-5D-5L

ObjectivesThe original 3-level EQ-5D (EQ-5D-3L) includes 5 dimensions with 3 levels of problems per dimension. Since 2010, a more sensitive version with 5 levels of problems per dimension (EQ-5D-5L) has become available. Population value sets have been developed for both versions of the questionnaire. The objective of this research was to develop a mapping function to link EQ-5D-3L responses to value sets for the EQ-5D-5L.MethodsVarious algorithms were developed to link EQ-5D-3L and EQ-5D-5L responses using data from an observational study including members of 10 subgroups (N = 3580) who completed both versions of the questionnaire. Nonparametric and ordinal logistic regression models were fit to the data and compared using Akaike’s information criterion (AIC) as well as the mean absolute error and root mean squared error of predictions. Results were contrasted qualitatively and quantitatively with those of an alternative copula-based approach.ResultsIncluding indicants of problems for other EQ-5D-3L dimensions as regressors in the modeling yielded the greatest improvement in prediction accuracy. Adding age and gender lowered the AIC without improving predictions, while including a latent factor lowered the AIC further and slightly improved predictive accuracy. Models that conditioned on problems in other EQ-5D-3L dimensions yielded more accurate predictions than the alternative copula-based approach in subgroups defined by age and gender.ConclusionWe present novel algorithms to map EQ-5D-3L responses to EQ-5D-5L value sets. The recommended approach is based on an ordinal logistic regression that disregards age and gender and accounts for unobserved heterogeneity using a latent factor.     

A Direct Comparison of the Measurement Properties of EQ-5D-5L,PROMIS-29+2 and PROMIS Global Health Instruments and EQ-5D-5L and PROPr Utilities in a General Population Sample

ObjectivesWe aimed to compare measurement properties of the 5-level version of EQ-5D (EQ-5D-5L) and 2 Patient-Reported Outcomes Measurement Information System (PROMIS) short forms, PROMIS-29+2 and PROMIS Global Health (PROMIS-GH-10), and of EQ-5D-5L and PROMIS-preference scoring system (PROPr) utilities.MethodsA cross-sectional survey was conducted in a general population sample in Hungary (N = 1631). We compared the following measurement properties at the level of items, domains, and utilities, the latter using corresponding US value sets: ceiling and floor, informativity (Shannon’s indices), agreement, convergent, and known-group validity. For the analyses, PROMIS items/domains were matched to EQ-5D-5L domains that cover similar concepts of health.ResultsThe majority of PROMIS items showed enhanced distributional characteristics, including lower ceilings and higher informativity than the EQ-5D-5L. Good convergent validity was established between EQ-5D-5L and PROMIS domains capturing similar aspects of health. Mean EQ-5D-5L utilities were substantially higher than those of PROPr (0.864 vs 0.535). EQ-5D-5L utilities correlated moderately or strongly with PROPr (r = 0.61), PROMIS-GH-10 physical (r = 0.68), and mental health summary scores (r = 0.53). EQ-5D-5L utilities decreased with age, whereas PROPr utilities slightly increased with age. EQ-5D-5L utilities discriminated significantly better in 12/28 (ratio of F-statistics) and 18/26 (area under the receiver-operating characteristics curve ratio) known groups defined by age, self-perceived health status, and self-reported physician-diagnosed health conditions, including hypertension, diabetes, coronary heart disease, chronic kidney disease, and stroke.ConclusionsThis study provides comparative evidence on the measurement properties of EQ-5D-5L, PROMIS-29+2, and PROMIS-GH-10 and informs decisions about the choice of instruments in population health surveys for assessment of patients’ health and for cost-utility analyses.     

Validation and comparison of the psychometric properties of the EQ-5D-3L and EQ-5D-5L instruments in Greece

Purpose

To validate and compare the psychometric properties of the EQ-5D-3L with the EQ-5D-5L classification systems in Greece.

Methods

Participants (n = 2279) over 40 years old, sampled from the greater area of Athens using a multistage stratified quota sampling method, completed both EQ-5D versions, while information was also collected on socio-demographics and health-related characteristics. The EQ-5D-5L and EQ-5D-3L were evaluated in terms of agreement, ceiling effects, redistribution and inconsistency, informativity, and convergent and known-groups validity.

Results

The agreement between the EQ-5D-3L and EQ-5D-5L was high (ICC = 0.85). Ceiling effects decreased significantly in the EQ-5D-5L in all domains (P < 0.001), with “usual activities” (?21.4 %) and “self-care” (?20.1 %) showing the highest absolute and “anxiety/depression” the highest relative reduction (?32.46 %). Inconsistency was low (5.7 %). The increase in prevalence of problems was larger than the decrease in their severity, resulting in a lower mean health utility for the EQ-5D-5L. Overall absolute and relative informativity improved by 70.5 % and 16.4 %, respectively, in the EQ-5D-5L. Both instruments exhibited good convergent and known-groups validity, with evidence of a considerably better convergent performance and discriminatory ability of the EQ-5D-5L.

Conclusions

Both EQ-5D versions demonstrated good construct validity and had consistent redistribution. The EQ-5D-5L system may be preferable to the EQ-5D-3L, as it exhibited superior performance in terms of lower ceiling effects, higher absolute and relative informativity, and improved convergent and known-groups validity efficiency.

     

Retrospectively Collected EQ-5D-5L Data as Valid Proxies for Imputing Missing Information in Longitudinal Studies

ObjectivesStudies face challenges with missing 5-level EQ-5D (EQ-5D-5L) data, often because of the need for longitudinal EQ-5D-5L data collection. There is a dearth of validated methodologies for dealing with missing EQ-5D-5L data in the literature. This study, for the first time, examined the possibility of using retrospectively collected EQ-5D-5L data as proxies for the missing data.MethodsParticipants who had prospectively completed a 3rd month postdischarge EQ-5D-5L instrument (in-the-moment collection) were randomly interviewed to respond to a 2nd “retrospective collection” of their 3rd month EQ-5D-5L at 6th, 9th, or 12th month after hospital discharge. A longitudinal single imputation was also used to assess the relative performance of retrospective collection compared with the longitudinal single imputation. Concordances between the in-the-moment, retrospective, and imputed measures were assessed using intraclass correlation coefficients and weighted kappa statistics.ResultsConsiderable agreement was observed on the basis of weighted kappa (range 0.72-0.95) between the mobility, self-care, and usual activities dimensions of EQ-5D-5L collected in-the-moment and retrospectively. Concordance based on intraclass correlation coefficients was good to excellent (range 0.79-0.81) for utility indices computed, and excellent (range 0.93-0.96) for quality-adjusted life-years computed using in-the-moment compared with retrospective EQ-5D-5L. The longitudinal single imputation did not perform as well as the retrospective collection method.ConclusionsThis study demonstrates that retrospective collection of EQ-5D-5L has high concordance with “in-the-moment” EQ-5D-5L and could be a valid and attractive alternative for data imputation when longitudinally collected EQ-5D-5L data are missing. Future studies examining this method for other disease areas and populations are required to provide more generalizable evidence.     

Comparison of the Psychometric Properties of the EQ-5D-3L-Y and EQ-5D-5L-Y Instruments in Spanish Children and Adolescents

ObjectivesThe study aimed to assess the reliability and validity of EQ-5D-5L-Y and to compare the performance of EQ-5D-5L-Y with EQ-5D-3L-Y in children and adolescents.MethodsThe Spanish versions of the 3L and 5L of EQ-5D for youths, were administered to children and adolescents from the general population. Feasibility and reliability were determined for the EQ-5D-5L-Y. The EQ-5D-5L-Y and EQ-5D-3L-Y were evaluated in terms of ceiling effects, informativity, and correlations with other generic measurements of health-related quality of life.ResultsA total of 714 healthy children and adolescents (10.7 ± 2.1 years old) from the general population participated in the study. Most of the sample reported full health status. The feasibility and reliability for the EQ-5D-5L-Y were acceptable, but the questionnaire showed a low convergent validity. Absolute informativity (Shannon index) showed a slight increase in all dimensions of the 5L compared with the 3L; nevertheless, there were only statistically significant differences between 5L and 3L in the dimension “feeling worried, sad, or unhappy” and also on the overall system. Relative informativity (Shannon evenness index) showed a decrease in the 5L compared with 3L for all dimensions, except for “looking after myself.” Correlations with other health measurements, in both 3L and 5L, showed similar results to those observed in the international EQ-5D-3L-Y validation study.ConclusionThe results show that EQ-5D-5L-Y is feasible, consistent, and reliable, but there are minor differences in the ceiling effect and informativity between the EQ-5D-5L-Y and EQ-5D-3L-Y versions in the general population.     

Comparing the psychometric properties of the EQ-5D-3L and EQ-5D-5L descriptive systems and utilities in atopic dermatitis

Background

Atopic dermatitis (AD) is a common chronic inflammatory skin disorder affecting up to 10% of adults. The EQ-5D is the most commonly used generic preference-accompanied measure to generate quality-adjusted life years (QALYs) for economic evaluations.

Objectives

We aimed to compare psychometric properties of the three-level and five-level EQ-5D (EQ-5D-3L and EQ-5D-5L) in adult patients with AD.

Methods

In a multicentre cross-sectional study, 218 AD patients with a broad range of severity completed the EQ-5D-3L, EQ-5D-5L, Dermatology Life Quality Index (DLQI) and Skindex-16. Disease severity outcomes included the Investigator Global Assessment, Eczema Area and Severity Index and the objective SCORing Atopic Dermatitis.

Results

A good agreement was established between the two EQ-5D versions with an intraclass correlation coefficient of 0.815 (95% CI 0.758–0.859, p < 0.001). Overall, 33 different health state profiles occurred in the EQ-5D-3L and 84 in the EQ-5D-5L. Compared to the EQ-5D-3L, ceiling effect was reduced for the mobility, self-care, usual activities and pain/discomfort dimensions by 4.6–11.5%. EQ-5D-5L showed higher average relative informativity (Shannon’s evenness index: 0.64 vs. 0.59). EQ-5D-5L demonstrated better convergent validity with EQ VAS, DLQI and Skindex-16. The two measures were similar in distinguishing between groups of patients based on disease severity and skin-specific quality of life with a moderate or large effect size (η² = 0.083–0.489).

Conclusion

Both instruments exhibited good psychometric properties in AD; however, the EQ-5D-5L was superior in terms of ceiling effects, informativity and convergent validity. We recommend the use of the EQ-5D-5L to measure health outcomes in clinical settings and for QALY calculations in AD.

     

Comparing EQ-5D-3L and EQ-5D-5L performance in common cancers: suggestions for instrument choosing

Purpose

To compare the performance of three-level EuroQol five-dimensions (EQ-5D-3L) and five-level EuroQol five-dimensions (EQ-5D-5L) among common cancer patients in urban China.

Methods

A hospital-based cross-sectional survey was conducted in three provinces from 2016 to 2018 in urban China. Patients with breast cancer, colorectal cancer, or lung cancer were recruited to complete the EQ-5D-3L and EQ-5D-5L questionnaires. Response distribution, discriminatory power (indicator: Shannon index [H′] and Shannon evenness index [J′]), ceiling effect (the proportion of full health state), convergent validity, and health-related quality of life (HRQoL) were compared between the two instruments.

Results

A total of 1802 cancer patients (breast cancer: 601, colorectal cancer: 601, lung cancer: 600) were included, with the mean age of 55.6 years. The average inconsistency rate was 4.4%. Compared with EQ-5D-3L (average: H′?=?1.100, J′?=?0.696), an improved discriminatory power was observed in EQ-5D-5L (H′?=?1.473, J′?=?0.932), especially contributing to anxiety/depression dimensions. The ceiling effect was diminished in EQ-5D-5L (26.5%) in comparison with EQ-5D-3L (34.5%) (p?<?0.001), mainly reflected in the pain/discomfort and anxiety/depression dimensions. The overall utility score was 0.790 (95% CI 0.778–0.801) for EQ-5D-3L and 0.803 (0.790–0.816) for EQ-5D-5L (p?<?0.001). A similar pattern was also observed in the detailed cancer-specific analysis.

Conclusions

With greater discriminatory power, convergent validity and lower ceiling, EQ-5D-5L may be preferable to EQ-5D-3L for the assessment of HRQoL among cancer patients. However, higher utility scores derived form EQ-5D-5L may also lead to lower QALY gains than those of 3L potentially in cost-utility studies and underestimation in the burden of disease.

     

Valuation of EuroQol Five-Dimensional Questionnaire,Youth Version (EQ-5D-Y) and EuroQol Five-Dimensional Questionnaire,Three-Level Version (EQ-5D-3L) Health States: The Impact of Wording and Perspective

Background

Valuations of health states were affected by the wording of the two instruments (EQ-5D-3L and EQ-5D-Y) and by the perspective taken (child or adult).

构建EQ-5D-5L量表效用积分体系的国际研究现状分析

为降低天花板效应,增强对较轻健康状态的区分能力,欧洲生命质量小组在EQ-5D-3L量表的基础上开发出新的EQ-5D-5L量表。EQ-5D量表的测量结果需通过效用积分体系转化成健康效用值,目前,加拿大、西班牙、英国、乌拉圭、韩国及荷兰已构建起基于本国人群健康偏好的EQ-5D-5L效用积分体系。通过对上述国家构建的研究方案、测量方法、健康状态选取、样本估计、数据处理及模型结果等进行介绍和比较,以此为中国EQ-5D-5L积分体系的构建提供参考。     

Peruvian Valuation of the EQ-5D-5L: A Direct Comparison of Time Trade-Off and Discrete Choice Experiments

Objectives(1) To produce Peruvian general population EQ-5D-5L value sets on a quality-adjusted life-year scale, (2) to investigate the feasibility of a “Lite” protocol less reliant on the composite time trade-off (cTTO), and (3) to compare cTTO and discrete choice experiment (DCE) value sets.MethodsA random sample of adults (N = 1000) in Lima, Arequipa, and Iquitos did a home interview; 300 were randomly selected to complete 11 cTTOs first. All respondents completed a DCE, including 10 latent-scale pairs (A/B) with 5 EQ-5D-5L attributes, and 12 matched pairs (A/B and B/C) with 5 EQ-5D-5L and one lifespan attributes. We estimated a cTTO heteroscedastic tobit (N = 300) model and 3 DCE Zermelo-Bradley-Terry models (N = 300, 700, and 1000).ResultsEach model produced a consistent value set (20 positive incremental parameters). Nevertheless, their lowest quality-adjusted life-year values differed greatly (cTTO: –1.076 [N = 300]; DCE: –0.984 [300], 0.048 [700], –0.213 [1000]). Compared with the cTTO, the DCE (N = 300) produced different parameters (Pearson’s correlation = 0.541), fewer insignificant parameters (0 vs 8), and fewer values less than 0 (26% vs 44%). Compared with the DCE (N = 300), the DCE (N = 700) produced higher values but similar parameters (Pearson’s correlation = 0.800).ConclusionsBesides producing EQ-5D-5L value sets for Peru, the results casts doubt about the feasibility of a Lite protocol like the one in this study. Additionally, fundamental differences between cTTO and DCE—without the existence of a gold standard—need further clarification. The choice between the two rational value sets produced in the current study is a matter of judgment and may have substantial policy implications.     

Comparing the measurement properties of the EQ-5D-5L and the EQ-5D-3L in hypertensive patients living in rural China

Purpose

The purpose of this study was to compare the measurement properties of two versions of EQ-5D (i.e.EQ-5D-3L and EQ-5D-5L) in hypertensive patients in rural China.

Methods

A cross-sectional survey was carried out in hypertensive patients in rural China. We compared the ceiling effects, redistribution properties, informativity, known-groups validity, and relative efficiency of the 3L and 5L and examined their agreement.

Results

A total of 11,412 patients were enrolled in our study. The mean EQ-5D index score was 0.84 (SD 0.21) according to the 5L and 0.86 (SD 0.17) according to the 3L. A good agreement was observed between the 3L and 5L. The overall ceiling effect decreased from 46.4% (3L) to 29.4% (5L). The Shannon index, H′ improved in all dimensions when used 5L. When used 3L, the median responses of all groups were consistent with 5L across the three dimensions of ‘mobility’, ‘self-care’, ‘usual activities’, while the median responses were inconsistent for the ‘pain/discomfort’ and ‘anxiety/depression’ dimensions. The 3L performed better in eight comorbidities in terms of F-statistics and six comorbidities in terms of the area under the receiver operating characteristic curves (AUROCs). The 5L performed better both in terms of the F-statistics and AUROCs in age, education level, anti-hypertensive medication use.

Conclusion

Taking all comparisons into account, we recommend the EQ-5D-5L for use in patients with hypertension in rural China.

     

Eliciting preferences to the EQ-5D-5L health states: discrete choice experiment or multiprofile case of best–worst scaling?

Choice-based methods have been used widely in assessing healthcare programs. This study compared the binary discrete choice experiment (DCE) and the multiprofile case of best–worst scaling (BWS) in eliciting preferences for the EQ-5D-5L. Forty-eight EQ-5D-5L health states were selected using a Bayesian efficient design and grouped into 24 pairs for the DCE tasks and 8 sets for the BWS tasks (each set has three health states). A total of 100 participants completed 12 pairs and 8 sets in a random order. A probit regression model and ranked order logistic regression model were used to estimate the latent utilities from the DCE and BWS, respectively. Both tasks were well understood by the majority of participants. The DCE tasks were relatively easier and took a shorter time to complete. The intraclass correlation coefficient (ICC) of the DCE was higher than that of the BWS. The variances associated with the latent utilities estimated from the DCE were larger than those from the BWS. The DCE is more feasible and reliable than the BWS in valuing the EQ-5D-5L. Future studies could focus on comparing the consistency and accuracy of these techniques in predicting the health utilities of the EQ-5D-5L.     

Comparing the psychometric properties of the EQ-5D-3L and EQ-5D-5L in cancer patients in Korea

Purpose

This study was conducted to assess the redistribution properties of the EQ-5D-3L when using the EQ-5D-5L and to compare the validity, informativity, and reliability of both EQ-5D-3L and EQ-5D-5L in Korean cancer patients.

Methods

Patients visiting one ambulatory cancer center self-administered the two versions of the EQ-5D and the EORTC QLQ-C30 questionnaire. Redistribution properties in each dimension of EQ-5D were analyzed between EQ-5D-3L and EQ-5D-5L. Informativity was evaluated using the Shannon entropy and ceiling effect. Convergent validity was evaluated by comparing the EQ-VAS, ECOG performance status, and EORTC QLQ-C30 subscales. Reliability was also evaluated in terms of test?Cretest reliability.

Results

All levels of the EQ-5D-3L substantially partitioned into associated levels of the EQ-5D-5L. The average inconsistency rate of the two versions was 3.5%. Absolute informativity was higher for the EQ-5D-5L than for the EQ-5D-3L, but their informative efficiency tended to be similar. The proportion of ??perfect health?? (11111) decreased from 16.8% in the EQ-5D-3L to 9.7% in the EQ-5D-5L. EQ-5D-5L demonstrated similar or higher correlations with the EQ-VAS, ECOG performance status, and EORTC QLQ-C30, than the EQ-5D-3L. The intraclass correlation coefficient of the EQ-5D-5L index was 0.77.

Conclusions

The EQ-5D-5L had greater informativity and lower rate in the ceiling effect than those values of the EQ-5D-3L. The EQ-5D-5L showed good construct validity and reasonable reliability. Therefore, considering these findings, the EQ-5D-5L may be preferable to the EQ-5D-3L.     

Measuring the acceptability of EQ-5D-3L health states for different ages: a new adaptive survey methodology

Background

Acceptable health and sufficientarianism are emerging concepts in health resource allocation. We defined acceptability as the proportion of the general population who consider a health state acceptable for a given age. Previous studies surveyed the acceptability of health problems separately per EQ-5D-3L domain, while the acceptability of health states with co-occurring problems was barely explored.

Objective

To quantify the acceptability of 243 EQ-5D-3L health states for six ages from 30 to 80 years: 1458 health state–age combinations (HAcs), denoted as the acceptability set of EQ-5D-3L.

Methods

In 2019, an online representative survey was conducted in the Hungarian general population. We developed a novel adaptive survey algorithm and a matching statistical measurement model. The acceptability of problems was evaluated separately per EQ-5D-3L domain, followed by joint evaluation of up to 15 HAcs. The selection of HAcs depended on respondents’ previous responses. We used an empirical Bayes measurement model to estimate the full acceptability set.

Results

1375 respondents (female: 50.7%) were included with mean (SD) age of 46.7 (14.6) years. We demonstrated that single problems that were acceptable separately for a given age were less acceptable when co-occurring jointly (p < 0.001). For 30 years of age, EQ-5D-3L health states of ‘11112’ (11.9%) and ‘33333’ (1%), while for 80 years of age ‘21111’ (93.3%) and ‘33333’ (7.4%) had highest and lowest acceptability (% of population), respectively.

Conclusion

The acceptability set of EQ-5D-3L quantifies societal preferences concerning age and disease severity. Its measurement profiles and potential role in health resource allocation needs further exploration.

     

The quality of life questionnaire EQ-5D-5L: psychometric properties and normative values for the general German population

Purpose

The health state classifier EQ-5D of the EuroQoL group has been expanded to a 5-level instrument (EQ-5D-5L), but studies on psychometric properties of this new instrument, applied to the general population, are rare.

Methods

A sample of 2,469 subjects, representatively selected from the German general population, was asked to fill in the EQ-5D-5L and several other questionnaires. Crude sum scores of the EQ-5D-5L were calculated and compared with scores derived from two sets of utilities, one from a German and one from a UK sample.

Results

The mean sum score (0–100 scale) was 91.5. Males reported better health states than females, and there was a nearly linear age trend. The list of the 45 most frequent health patterns (those with at least 0.2 % of the respondents) showed that almost half of the participants (47.5 %) responded being in the optimal health state, indicating a ceiling effect. Correlations between EQ-5D-5L scores and other questionnaires were very similar for all three scoring systems of the EQ-5D-5L. Finally, normative scores are given on the basis of sum scores.

Conclusions

The applicability of the EQ-5D-5L in the general population is limited because of the skewness. Sum scores are useful because of their simplicity, international generalizability, and construct validity.     

Less Is More: Cross-Validation Testing of Simplified Nonlinear Regression Model Specifications for EQ-5D-5L Health State Values

Background

The conventional method for modeling of the five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) health state values in national valuation studies is an additive 20-parameter main-effects regression model. Statistical models with many parameters are at increased risk of overfitting—fitting to noise and measurement error, rather than the underlying relationship.

Head-to-head comparison between the EQ-5D-5L and the EQ-5D-3L in general population health surveys

Background

The EQ-5D has been frequently used in national health surveys. This study is a head-to-head comparison to assess how expanding the number of levels from three (EQ-5D-3L) to five in the new EQ-5D-5L version has improved its distribution, discriminatory power, and validity in the general population.

Methods

A representative sample (N?=?7554) from the Catalan Health Interview Survey 2011–2012, aged ≥18, answered both EQ-5D versions, and we evaluated the response redistribution and inconsistencies between them. To assess validity of this redistribution, we calculated the mean of the Visual Analogue Scale (VAS), which measures perceived health. The discriminatory power was examined with Shannon Indices, calculated for each dimension separately. Spanish preference value sets were applied to obtain utility indices, examining their distribution with statistics of central tendency and dispersion. We estimated the proportion of individuals reporting the best health state in EQ-5D-5L and EQ-5D-3L within groups of specific chronic conditions and their VAS mean.

Results

A very small reduction in the percentage of individuals with the best health state was observed, from 61.8% in EQ-5D-3L to 60.8% in EQ-5D-5L. In contrast, a large proportion of individuals reporting extreme problems in the 3 L version moved to severe problems (level 4) in the 5 L version, particularly for pain/discomfort (75.5%) and anxiety/depression (66.4%). The average proportion of inconsistencies was 0.9%. The pattern of the perceived health VAS mean confirmed the hypothesis established a priori, supporting the validity of the observed redistribution. Shannon index showed that absolute informativity was higher in the 5 L version for all dimensions. The means (SD) of the Spanish EQ-5D-3L and EQ-5D-5L indices were 0.87 (0.25) and 0.89 (0.22). The proportion of individuals with the best health state within each specific chronic condition was very similar, regardless of the EQ-5D version (≤?30% in half of the 28 chronic conditions).

Conclusion

Although the proportion of individuals with the best possible health state is still very high, our findings support that the increase of levels provided by the EQ-5D-5L contributed to the validity and discriminatory power of this new version to measure health in general population, as in the national health surveys.

     

Cost-Utility Analysis Using EQ-5D-5L Data: Does How the Utilities Are Derived Matter?

Objectives

To explore how the use of EQ-5D-5L value set and crosswalk from EQ-5D-5L to EQ-5D-3L (and use of 3L value set) would affect cost-effectiveness analysis results for England and six other countries (Canada, the Netherlands, China, Japan, South Korea, and Singapore).