It's pretty interesting to look at research on this; it's not just SES and literacy. Nor is genetics to blame in many situations. I don't have access right now

It's pretty interesting to look at research on this; it's not just SES and literacy. Nor is genetics to blame in many situations. I don't have access right now to the enormous pile of literature I have at home about this (printed on paper!!!) but as an example look at variation in wait time in emergency rooms, for kids, by race/ethnicity. To address your question about Hispanics directly in this situation, Hispanic kids waited 10.4% longer than white kids for care in the same emergency rooms. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2796312/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2796312/ ED wait times are an interesting little side branch of study because they're a proxy for how people are treated by the medical establishment; they're not genetic or based on lifestyle choices; they don't rely on educational level etc.; and they're unconscious: no one in the ED is a jerk saying "let that person wait longer because of their background!"