Michels KB, Rothman KJ. Update on unethical use of placebos in randomised trials. Bioethics. 2003 Apr;17(2):188-204.
Espaulella J, Guyer H, Diaz-Escriu F, Mellado-Navas JA, Castells M, Pladevall-Vila M. Nutritional supplementation of elderly hip fracture patients. A randomized, double-blind, placebo-controlled trial. Age Ageing. 2000 Sep;29(5):425-31.
Sorensen HT, Sabroe S, Olsen J, Rothman KJ, Gillman MW, Fisher P. Birth weight as a predictor of young men's intelligence. A historical cohort study. Ugeskr Laeger. 1999 Feb 8;161(6):791-3.