Health Disparities: Taking on the Challenge.

The existence of significant health disparities beyond those associated with race/ethnicity, poverty, and lack of health care has drawn the attention of researchers to the "challenge of the gradient." Studies progressed from describing cross-sectional associations between disease risk and a single aspect of social disadvantage to identifying mechanisms by which these associations occur, encompassed objective and subjective measures of social status and stress processes, and used multilevel, dynamic models over the life course. The next stage is developing effective interventions targeting both the bases of disadvantage and the mediating pathways to reduce persistent disparities.