Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 Feb;87(2):151-60.
doi: 10.1016/j.mayocp.2011.11.009.

Generalizability of epidemiological findings and public health decisions: an illustration from the Rochester Epidemiology Project

Jennifer L St Sauver  1 , Brandon R Grossardt, Cynthia L Leibson, Barbara P Yawn, L Joseph Melton 3rd, Walter A Rocca
Affiliations

Generalizability of epidemiological findings and public health decisions: an illustration from the Rochester Epidemiology Project

Jennifer L St Sauver et al. Mayo Clin Proc. 2012 Feb.

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.

PubMed Disclaimer

Figures

FIGURE 1
FIGURE 1
Population pyramids for Olmsted County, Minnesota, from 1970 to 2008. This figure is based on publicly available US Census data.
FIGURE 2
FIGURE 2
Top, a geographic map of the 4 regions that were compared in this study: Olmsted County, the state of Minnesota, the Upper Midwest, and the entire US. At the 2000 US Census, the Olmsted County population of 124,277 persons represented 2.5% of the total Minnesota population (4,919,479 persons) and 0.9% of the Upper Midwest population (14,606,522 persons). In turn, the Upper Midwest population of 14,606,522 persons represented 5.2% of the total US population (281,421,906 persons). Bottom, 3 population pyramids comparing Olmsted County (red-cross profile) with the population of Minnesota, the Upper Midwest, and the entire United States. For the pyramids, we used 5-year age groups (see also Figure 1). The bar graphs compare the 4 study populations for ethnicity and socioeconomic indicators (bars are color-coded as per the top geographic map). This figure is based on publicly available US Census data.
FIGURE 3
FIGURE 3
Age- and sex-specific mortality rates for Olmsted County, the state of Minnesota, and the entire United States in 2000 displayed using a logarithmic scale. Mortality rates were computed as the probability of dying within 1 year of a given reference age (qx in standard life tables notation). This figure is based on published data from the National Center for Health Statistics (United States), the Minnesota State Demographic Center (Minnesota), and the Minnesota Center for Health Statistics (Olmsted County).
See this image and copyright information in PMC

References

    1. Anderson D.W., Mantel N. On epidemiologic surveys. Am J Epidemiol. 1983;118(5):613–619. - PubMed
    1. Deming W.E. On the use of judgment-samples. Rep Statist Applications. 1976;23:25–31.
    1. Weiss N.S., Koepsell T.D., Psaty B.M. Generalizability of the results of randomized trials. Arch Intern Med. 2008;168(2):133–135. - PubMed
    1. Plan and operation of the Third National Health and Nutrition Examination Survey, 1988-94: Series 1: Programs and collection procedures. Vital Health Stat 1. 1994;(32):1–407. - PubMed
    1. Melton L.J., III History of the Rochester Epidemiology Project. Mayo Clin Proc. 1996;71(3):266–274. - PubMed

Publication types