Christensen T, Riis AH, Hatch EE, Wise LA, Nielsen MG, Rothman KJ, Toft Sorensen H, Mikkelsen EM. Costs and efficiency of online and offline recruitment methods: a web-based cohort study. J Med Internet Res. 2017 Mar 1;19(3):e58. doi: 10.2196/jmir.6716
Hutchison RW, Anastassopoulos K, Vallow S, Mordin M, Olson W, Hewitt D, Sikirica V. Intravenous patient-controlled analgesia pump and reservoir logistics: results from a multicenter questionnaire. Hosp Pharm. 2007 Nov 1;42(11):1036-44.
Milunsky A, Morris JS, Jick H, Rothman KJ, Ulcickas M, Jick SS, Shoukimas P, Willett W. Maternal zinc and fetal neural tube defects. Teratology. 1992 Oct 1;46(4):341-8.
Rothman KJ, Fyler DC. Association of congenital heart defects with season and population density. Teratology. 1976 Feb;13(1):29-34.