Social Medicine Research Unit, Medical Research Council
Accepted 7 September 2007
†Read in opening a discussion at the Section of Preventive Medicine and Infectious Diseases at the Annual Meeting of the British Medical Association, Glasgow, 1954, and since expanded. First published BMJ 1955;2:395–401. Reprinted with permission.
International Journal of Epidemiology 36(6):p 1165-1172, December 2007.
