Combining education and income into a socioeconomic position score for use in studies of health inequalities

Abstract

Background In studies of social inequalities in health, there is no consensus on the best measure of socioeconomic position (SEP). Moreover, subjective indicators are increasingly used to measure SEP. The aim of this paper was to develop a composite score for SEP based on weighted combinations of education and income in estimating subjective SEP, and examine how this score performs in predicting inequalities in health-related quality of life (HRQoL). Methods We used data from a comprehensive health survey from Northern Norway, conducted in 2015/16 (N = 21,083). A composite SEP score was developed using adjacent-category logistic regression of subjective SEP as a function of four education and four household income levels. Weights were derived based on these indicators’ coefficients in explaining variations in respondents’ subjective SEP. The composite SEP score was further applied to predict inequalities in HRQoL, measured by the EQ-5D and a visual analogue scale. Results Education seemed to influence SEP the most, while income added weight primarily for the highest income category. The weights demonstrated clear non-linearities, with large jumps from the middle to the higher SEP score levels. Analyses of the composite SEP score indicated a clear social gradient in both HRQoL measures. Conclusions We provide new insights into the relative contribution of education and income as sources of SEP, both separately and in combination. Combining education and income into a composite SEP score produces more comprehensive estimates of the social gradient in health. A similar approach can be applied in any cohort study that includes education and income data.

Depression, Brain Structure and Socioeconomic Status: A UK Biobank Study

“…They have also both been associated with depression in previous studies (Rai et al, 2013; Akhtar-Danesh et al, 2007; Romans et al, 2011). It has also been demonstrated that combining education and income into a composite measure of socioeconomic position creates a more robust estimate of the social gradient of health than considering them separately (Lindberg et al, 2022).…”

Mediation Analyses of the Mechanisms by Which Socioeconomic Status, Comorbidity, Stroke Severity, and Acute Care Influence Stroke Outcome

“…The combination of education and income into a composite measure has been shown to produce more comprehensive estimates of social inequalities in health. 50…”

“…The combination of education and income into a composite measure has been shown to produce more comprehensive estimates of social inequalities in health. 50 A limitation of our study is that no data on occupation were available, and hence, we could not capture, for example, aspects related to work-based psychosocial processes and environmental exposures. 48 However, most of the patients were elderly individuals and likely to be retired, making occupation less important as a determinant of SES in our cohort.…”

Stronger association of perceived health with socio-economic inequality during COVID-19 pandemic than pre-pandemic era

“…Higher level of educational attainment facilitates social contact of elderly population (in their mid-60s) during the COVID-19 pandemic [56]. In addition to the availability of charitable assistance [57], educational attainment [13,58] and monthly household income [13,[57][58][59] could affect treatment seeking intention, perceived physical health, and health-related quality of life in patients diagnosed with physical disease (such as pain disorder, stroke, or congenital heart disease). Moreover, college education could facilitate navigation and utilization of a complex healthcare system [60].…”