Does EQ-5D Tell the Whole Story? Statistical Methods for Comparing the Thematic Coverage of Clinical and Generic Outcome Measures, With Application to Breast Cancer.

OBJECTIVES: This study aimed to develop the following: (1) methods for assessing claims in any specific application that a generic outcome measure, such as EQ-5D is deficient in its coverage of 1 or more specified domains, and (2) a simple method of judging whether any such deficiency is likely to be quantitatively important enough to call into question evaluations based on the generic instrument. Also to demonstrate the applicability of the methods in the important area of breast cancer. METHODS: The methodology requires a data set with observations from a generic instrument (eg, EQ-5D) and also a more comprehensive clinical instrument (eg, FACT-B [Functional Assessment of Cancer Therapy - Breast]). A standardized 3-component statistical analysis is proposed for investigating the claim that the generic measure inadequately captures some specified dimension covered by the latter instrument. A theoretically based upper bound on the bias induced by deficient coverage is derived based on the assumption that the designers of the (k-dimensional) generic instrument did succeed in identifying the k most important domains. RESULTS: Data from the MARIANNE breast cancer trial were analyzed and results suggested that impacts on personal appearance and relationships may be inadequately represented by EQ-5D. Nevertheless, the indications are that the bias in quality-adjusted life-year differences from deficient coverage by EQ-5D is likely to be modest. CONCLUSIONS: The methodology offers a systematic approach to determining whether there is clear evidence consistent with any claim that a generic outcome measure such as EQ-5D misses an important specific domain. The approach is readily implementable using data sets that are available in many randomized controlled trials.

Economic gradients in loneliness, social isolation and social support: Evidence from the UK Biobank.

Despite the substantial literature on how loneliness is associated with poor health and premature mortality, there is little detailed research on the extent of its economic gradients. We provide this evidence using a sample of around 400,000 respondents aged 40-70 years from the UK Biobank, who were assessed between 2006 and 2010. We focus on differences in loneliness, as well as social isolation and a lack of social support, across educational attainment, household income, local area deprivation, and recent experience of financial stress. We employ two statistical approaches, the first exploiting the large sample size and detailed geographical information about where respondents live, so we compare individuals who differ in their economic status but reside within the same postcode district. The second approach exploits the fact that for around 36,000 respondents we observe their social health and economic circumstances at two points in time (second wave of assessment conducted between 2014 and 2020), so we conduct a panel analysis that accounts for intercorrelations between the social health measures, and controls for incomplete follow-up of panel members. Across both approaches, we find a substantially higher probability of reporting loneliness, social isolation and a lack of social support, for men and women with lower economic status. Together with the existing health-loneliness literature, these findings establish a 'loneliness pathway' contributing to health inequalities, and consequently a need for effective interventions that might address loneliness and social isolation as part of a broad policy initiative on health inequalities.

Birth-cohort trends in older-age functional disability and their relationship with socio-economic status: Evidence from a pooling of repeated cross-sectional population-based studies for the UK.

We examine birth-cohort trends behind recent changes in the prevalence of functional disability in the older population living in private households in the United Kingdom (UK). By using three different socio-economic indicators available in the nationally representative cross-sectional data on older individuals interviewed between 2002 and 2012 in the Family Resource Survey (FRS) (96,733 respondents), we investigate the extent to which the overall trends have been more favourable among more advantaged than disadvantaged socioeconomic groups. Compared to the cohort of people born in 1924, successive cohorts of older men have lower odds of having at least one functional difficulty (FD), whereas no significant trend was found for women. Among people with at least one FD, however, the number of disabilities increases for each successive cohort of older women (incidence rate ratio 1.027, 95% confidence interval 1.023 to 1.031, P < 0.001) and men (incidence rate ratio 1.028, 95% confidence interval 1.024 to 1.033, P < 0.001). By allowing interactions between birth cohort and SES indicators, a significant increasing cohort trend in the number of reported FDs was found among older men and women at lower SES, whereas an almost stable pattern was observed at high SES. Our results suggest that the overall slightly increasing birth-cohort trend in functional difficulties observed among current cohorts of older people in the UK hides underlying increases among low SES individuals and a relative small reduction among high SES individuals. Further studies are needed to understand the causes of such trends and to propose appropriate interventions. However, if the SES differentials in trends in FDs observed in the past continue, this could have important implications for the future costs of the public system of care and support for people with care needs.