Response to Invited Commentary Chen et al. Respond to “Bias in Socioeconomic Health Disparities—Comments”

We thank Dr. Talih for his commentary (1) on our paper regarding temporal comparisons of health disparities (2). Curiously, Talih agrees with our key conclusion: Changing relationships between dimensions of socioeconomic position (e.g., education and income) can result in bias when compar-ing disparities over time, especially when researchers rely on a single measured indicator of socioeconomic position. What are Talih’s criticisms? They are that we 1) “reduce” education to income and treat education as a linear variable, disregarding the importance of credentials; 2) violate causal agnosticism via our use of causal directed acyclic graphs; and 3) aver that the slope index of inequality (SII) was not intended to be used for temporal comparisons. These erroneous concerns are all easy to address. First, we concur with Talih that education cannot be reduced to income and likely influences health through pathways above and beyond its association with material resources. Nevertheless, extensive evidence exists regarding associations between income and health and dramatic changes in both educational attainment and its relationship with income (3, 4). Thus, even if education has strong independent effects on health (e.g., via literacy), estimates of educational disparities in health (as shown by our models) will reflect both the independent mech-anisms connecting education to health and the likely substan-tial effect of pathways involving income and material resources (refer to our Web Appendix 2 available a