[1] NYU, Dept Populat Hlth, Div Comparat Effect & Decis Sci, Grossman Sch Med, New York, NY USA
[2] NYU, Dept Populat Hlth, Div Epidemiol, Grossman Sch Med, 227 East 30th St,Off 624, New York, NY 10016 USA
[3] Univ Maryland, Sch Publ Hlth, Dept Epidemiol & Biostat, College Pk, MD 20742 USA
[4] Univ N Carolina, Dept Obstet & Gynecol, Chapel Hill, NC 27515 USA
[5] Univ Connecticut, Dept Psychol Sci, Storrs, CT USA