Epidemiological Studies : Studies of the distribution of disease and other health issues as related to age, sex, race, ethnicity, occupation, economic status, or other factors
U.S. Environmental Protection Agency, Radiation Glossary, Office of Radiation and Indoor Air Radiation Protection Division, Washington, DC, USA 2013. http://www.epa.gov/radiation/glossary/index.html#a , (Dzstr/ Rad Emr - Amer) {823}