Underestimating health disparities based on self-reported data

Queen Mary University of LondonSep 18 2024

A first-of-its kind analysis of data collected from England's annual health survey found that of the people who reported their health as 'poor', those living in areas of high deprivation are likely to have worse health than those living in the least deprived areas. 

This could mean that we are underestimating health inequalities across England, and could have implications for public health practice and policy informed by self-reported health data. 

Researchers from Queen Mary University of London and the University of Warwick analysed data collected from over 14,000 participants of the 2017 and 2018 waves of the Health Survey for England. They compared participants' simple self-reported health (SRH) statements with a more detailed health-related quality of life measure, EQ-5D, which was collected at the same time. The analysis assessed differences in the relationship between SRH and EQ-5D by Index of Multiple Deprivation (IMD) quintile, a widely-used measure of deprivation. 

The study found that self-reported good health declined with increasing deprivation, from 82.9% in the least deprived quintile to 63.9% in the most deprived quintile. Analysis also found that participants living in the most deprived two quintiles of areas in England who report poor health have lower EQ-5D scores – and therefore worse health – than would be expected based on their deprivation quintile and SRH status. 

While additional research is needed to explore this further and quantify any impact on measures such as healthy life expectancy that incorporate SRH data, this study suggests that basing public health funding and interventions on SRH alone could result in an underestimation of health inequalities based on deprivation. 

Self-reported health is a widely used measure of health, most importantly in England we use it to calculate healthy life expectancy. Our analysis suggests that using self-reported health might underestimate socio-economic health inequalities, which may mean that resources and interventions are not appropriately targeted to the most vulnerable neighborhoods or people." 

Oyinlola Oyebode, Professor of Public Health, Queen Mary University of London

Rosanna Fforde, Honorary Research Fellow at the University of Warwick and Consultant in Public Health at Sandwell Council, said: "Understanding any systematic variation in how people self-report their health is important because this single question measure of health is so widely used, including in large surveys and the Census. The resultant large number of responses provides us with valuable granular insights into patterns of health, but this also means that it is important to explore whether 'good' health means the same thing to everyone."