1. Give an example of a research question for investigating racial/ethnic health disparities where: [1] SES is a confounder; [2] SES is an effect modifier; [3] SES is a mediator. Briefly discuss the interpretations/implications of each approach as it relates to understanding health disparities by race/ethnicity.
Confounder: Children of color with cancer have worse long term survival than White children in the US. In a study designed to assess racial disparities among children with cancer, SES could be a confounder by impacting comorbidities (prior history of another chronic illness, inadequate nutrition, etc.) as well as cancer survivorship (via access to care acute and long-term care, caretaker availability and healthcare literacy, environmental infectious exposure).
Effect Modifier: What is the effect of race/ethnicity on peripartum mortality? Black women have disproportionately high peripartum across different levels of socioeconomic status. However, if Black women of higher SES have access to care, they could have better outcomes than Black women of lower SES even though their peripartum mortality is higher than that of other racial/ethnic groups. In this case, SES would be an effect modifier of the relationship between experienced racism (race/ethnicity) and peripartum mortality.
Mediator: A hypothetical study of diabetes mellitus among Black Americans. In the US, Black individuals have higher prevalence of type II diabetes compared to other racial groups. SES functions as a mediator in this structure because Black individuals of lower SES are more likely to live in food deserts without access to fresh or healthy foods, whereas individuals of higher SES would be more likely to have access to fresh and healthy foods and would likely have prevalence of TIIDM similar to other racial groups. In this case, the increased prevalence of TIIDM is mediated by lower SES.
2. Describe a potential effect modifier, mediator, or contextual variable (for definition of contextual variable, see Diez-Roux reading) for an association of interest to you and relevant to health disparities. For example, for investigating the association between education and hypertension, I might be interested in evaluating whether the association between years of education and hypertension is different for Black men than for White men. Describe how you would study whether this relationship exists.
I am interested in studying how providers communicate with children with life-limiting illnesses and their families, particularly around prognosis, setting goals of care, and end of life. It would be interesting to study whether the association between parental employment and the quality of communication between providers and parents is different in different racial groups.
This sort of study could be accomplished by chart review to assess how many documented conversations exist in the chart, the depth of the discussions, the duration of the conversations when documented, and employment status of the parent(s). It would also be interesting to interview providers and families to gain understanding of their perceptions of the conversations (Did providers have differential perception of patient and family interest in the conversations or comprehension? Do patients/families report different levels of understanding of their circumstances and choices?)