By H. Gilbert Welch, M.D., M.P.H. (who gave the Pease Symposium presentation in Bend in 2014) and Elliott S. Fisher, M.D., M.P.H.
The authors found that high-income counties have experienced markedly greater increases than low-income counties breast, prostate and thyroid cancer, and melanoma. What explains this pattern? They hypothesize that the proximal cause is that wealthier people are exposed to increased observational intensity: they are likely to be screened more often and by means of tests (such as magnetic resonance imaging) that can detect smaller abnormalities, undergo more follow-up testing, and undergo more biopsies, and they may be served by health systems that have a lower threshold for labeling results as abnormal. More cancers are therefore found. Thus overdiagnosis is more problematic in higher income communities, like Bend.