James Lind was a Scottish physician. He was a pioneer of naval hygiene in the Royal Navy. By conducting one of the first ever clinical trials, he developed the theory that citrus fruits cured scurvy. He argued for the health benefits of better ventilation aboard naval ships, the improved cleanliness of sailors' bodies, clothing and bedding, and below-deck fumigation with sulphur and arsenic. He also proposed that fresh water could be obtained by distilling sea water. His work advanced the practice of preventive medicine and improved nutrition. Scurvy is a disease now known to be caused by a Vitamin C deficiency, but in Lind's day, the concept of vitamins was unknown. Vitamin C is necessary for the maintenance of healthy connective tissue. In 1740 the catastrophic result of Anson's circumnavigation attracted much attention in Europe; out of 1900 men, 1400 had died, most of them allegedly from having contracted scurvy. According to Lind, scurvy caused more deaths in the British fleets than French and Spanish arms.

Austin Bradford Hill – Pivotal figure in the modern development of clinical trials English epidemiologist and statistician, pioneered the randomized clinical trial and, together with Richard Doll, demonstrated the connection between cigarette smoking and lung cancer. Hill is widely known for pioneering the "Bradford Hill" criteria for determining a causal association. In 1922 Hill went to work for the Industry Fatigue Research Board. He was associated with the medical statistician Major Greenwood and, to improve his statistical knowledge, Hill attended lectures by Karl Pearson. When Greenwood accepted a chair at the newly formed London School of Hygiene and Tropical Medicine, Hill moved with him, becoming Reader in Epidemiology and Vital Statistics in 1933 and Professor of Medical Statistics in 1947.