Records

Commentary on: Theobald GW (1937). Effect of calcium and vitamin A and D on incidence of pregnancy toxaemia. Lancet 2:1397-9.

Cite as: Olsen SF (1999). Theobald's trial in 1936 incorporated some aspects of randomisation. BMJ 318:1352, and Olsen SF (1998). The first clinical trial with true randomisation of individuals. BMJ.com.

Authors contact details: Sjúrður F Olsen, Danish Epidemiology Science Centre, Statens Serum Institut 5 Artillerivej, DK-2300 Copenhagen C, Denmark. E-mail: sfo@ssi.dk

Links to BMJ Commentaries: