Generalizability of Epidemiological Findings and Public Health Decisions: An Illustration From the Rochester Epidemiology Project

Abstract

Objective: To illustrate the problem of generalizability of epidemiological findings derived from a single population using data from the Rochester Epidemiology Project and from the US Census. Methods: We compared the characteristics of the Olmsted County, Minnesota, population with the characteristics of populations residing in the state of Minnesota, the Upper Midwest, and the entire United States. Results: Age, sex, and ethnic characteristics of Olmsted County were similar to those of the state of Minnesota and the Upper Midwest from 1970 to 2000. However, Olmsted County was less ethnically diverse than the entire US population (90.3% vs 75.1% white), more highly educated (91.1% vs 80.4% high school graduates), and wealthier ($51,316 vs $41,994 median household income; 2000 US Census data). Age-and sex-specific mortality rates were similar for Olmsted County, the state of Minnesota, and the entire United States. Conclusion: We provide an example of analyses and comparisons that may guide the generalization of epidemiological findings from a single population to other populations or to the entire United States.

The Impact of Subclinical Disease and Mechanism of Detection on the Rise in Thyroid Cancer Incidence: A Population-Based Study in Olmsted County, Minnesota During 1935 Through 2012

“…A study comparing the characteristics of the Olmsted County, Minnesota population with the characteristics of other populations revealed that age, sex, and ethnic characteristics of Olmsted County were similar to those of the state of Minnesota and the Upper Midwest from 1970 to 2000. However, Olmsted County was less ethnically diverse than the entire U.S. population (15). Thus, it is possible that the relationship of the mechanism of detection and the incidence of thyroid cancer varies depending on the source of data; however, the similarities between our thyroid cancer incidence rate in 2000-2012 and the nationally representative SEER cancer incidence rate incidence rate in 2009 suggest that the variation may be minimal.…”

Association Between Adiposity and Lean Mass With Long‐Term Cardiovascular Events in Patients With Coronary Artery Disease: No Paradox

“…Another limitation is the limited diversity of those living in Olmsted County, a population that is mostly non‐Hispanic white. However, the epidemiological characteristics of Olmsted County for age, sex, morbidity, and mortality are comparable to those of the state of Minnesota and the entire United States 40. Last, misclassification bias could potentially affect our sample; our estimates are based on a single measure of body composition as the exposure variable, assuming that body composition will not change through follow‐up.…”

Prevalence of Total Hip and Knee Replacement in the United States

“…Regarding relative mortality data post-total hip and knee replacement, our estimates are almost identical to patterns observed for other large cohorts or national data. Although the local population is less ethnically diverse than the entire U.S. population, mortality rates are similar 25,26 . Similarly, the contralateral procedure estimates are consistent with those in the published literature 27 .…”