Explaining Heterogeneous Gradients in Health: The Population Education Transition (P.E.T.) Curve

William C. Smith, Pennsylvania State University
Daniel Salinas, Pennsylvania State University
David Baker, Pennsylvania State University
Haram Jeon, Pennsylvania State University
Emily Anderson, Pennsylvania State University

The Population Education Transition (P.E.T.) curve is a new explanatory hypothesis that accounts for heterogeneity in the education-health gradient. Despite the well-known positive association between education and health, recent research finds reverse education gradients for a number of health risks and conditions. The P.E.T. curve places these seemingly contradictory results in the context of long-term population transitions, postulating that a U-inverted curve around a social vaccine point is the underlying functional form of the overall education-health association. Interactions between multiple effects of education on health risks and preventive factors and changing population contexts explain the different positioning of the social vaccine point on the P.E.T. curve. Reassessments of past epidemiological research on education’s role over the historical progression of four diseases (HIV/AIDS, obesity, smoking, and chronic disease) and associated population transitions are provided to illustrate the utility of the P.E.T. curve.