The Nurses' Health Study 3 was developed in 2010 by Drs. Jorge Chavarro, Walter Willett, Janet Rich-Edwards, and Stacey Missmer. The study includes investigators from the Channing Division of Network Medicine at Brigham and Women's Hospital, Harvard Medical School, and Harvard T.H. Chan School of Public Health. The original population contained females 19-49 in age and expanded to include Canadian subjects. Unlike the predecessor studies, the NH3 includes participants of both male and female genders in 2015. Jorge Chavarro has been the principal investigator of Nurses' Health Study 3 since its 2010 inception.