We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleEpidemiology. When an entire country is a cohort.AuthorsFrank LPublicationScience (New York, N.Y.), 2000, Vol 287, Issue 5462, p2398ISSN0036-8075Publication typearticleDOI10.1126/science.287.5462.2398