Austin Bradford Hill

Sir Austin Bradford Hill FRS (8 July 1897 – 18 April 1991), English epidemiologist and statistician, pioneered the randomized clinical trial and, together with Sir Richard Doll, demonstrated the connection between cigarette smoking and lung cancer.

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 * "All scientific work is incomplete – whether it be observational or experimental. All scientific work is liable to be upset or modified by advancing knowledge. That does not confer upon us a freedom to ignore the knowledge we already have, or to postpone the action that it appears to demand at a given time."
 * “The Environment and Disease: Association or Causation?,” Proceedings of the Royal Society of Medicine, 58 (1965), 295-300