Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
History of the Department of Epidemiology of the Johns Hopkins Bloomberg School of Public Health. Reproduced from Celentano (Am J Epidemiol. 2016;183(5):355–361) (8) by permission of Oxford University Press. MACS, Multicenter AIDS Cohort Study.
