Major Greenwood junior was born in Shoreditch in London's East End, the only child of a doctor in general practice there. ("Major" was his forename, not a military rank.) He was educated on the classical side at Merchant Taylors' School and went on to study medicine at University College London and the London Hospital. On qualifying in 1904 he worked for a time as assistant to his father but after a few months he gave up clinical practice for good. He went to work as a demonstrator for the physiologist Leonard Hill (father of the future statistician Austin Bradford Hill) at the London Hospital Medical College. Leonard Hill recalled, "By recognising the ability of a student with nothing behind him to show his worth and by appointing him my assistant I may claim to have started Greenwood on his career." While Greenwood made a good start in physiological research he was already drawn to statistics; his first paper in Biometrika appeared in 1904. After a period of study with Karl Pearson he was appointed statistician to the Lister Institute in 1910. There he worked on a wide range of problems, including a study of the effectiveness of inoculation with the statistician Udny Yule. In the First World War Greenwood first served in the Royal Army Medical Corps but then was put in charge of a medical research unit at the Ministry of Munitions. There he investigated the health problems associated with factory work, one result of which was an influential study of accidents which he produced with Yule. In 1919 Greenwood joined the newly created Ministry of Health with responsibility for medical statistics. In 1928 he became the first professor of Epidemiology and Vital Statistics at the London School of Hygiene and Tropical Medicine where he stayed until he retired in 1945. He established a group of researchers, of whom the most important was Austin Bradford Hill. Greenwood played the same role in A. B. Hill’s career as Hill’s father had played in his.
Engaged in medical research. Has applied the statistical method to the elucidation of many problems of physiology, pathology, hygiene and epidemiology. Is the author, or joint author, of more than sixty papers dealing with these applications, including important contributions to the experimental study of epidemiology (Journ Hyg, 24, 1925, Greenwood and Topley; ibid, 25, 1926, Greenwood, Newbold, Topley and Wilson). Has done much to encourage and develop the use of modern statistical methods by medical laboratory investigators, and, as Chairman of the Medical Research Council's Statistical Committee, to secure the adequate planning and execution of field investigations.
Greenwood produced a large body of research, was the first holder of important positions in modern medical statistics and wrote extensively on the history of his subject, but as Austin Bradford Hill wrote in his obituary, "in the future, it may well indeed seem that one of his greatest contributions, if not the greatest, lay merely in his outlook, in his statistical approach to medicine, then a new approach and one long regarded with suspicion. And he fought this fight continuously and honestly—for logic for accuracy, for ‘little sums.’"
A statistical method invented by Major Greenwood in a statistical study of infectious diseases is still used in present day research. The Greenwood statistic was used to discover that there is some kind of order in the placement of genes on the chromosomes of living things and this inspired a new look at epigenetics, which is now considered to be equally as important as genetics in how living organisms develop and evolve.
- Greenwood, M. (1904). "A First Study of the Weight, Variability, and Correlation of the Human Viscera, with Special Reference to the Healthy and Diseased Heart". Biometrika 3: 63. doi:10.1093/biomet/3.1.63.
- Greenwood, M; Yule, G. U. (1915). "The Statistics of Anti-typhoid and Anti-cholera Inoculations, and the Interpretation of such Statistics in general". Proceedings of the Royal Society of Medicine 8 (Sect Epidemiol State Med): 113–94. PMC 2004181. PMID 19978918.
- Greenwood, Major and Udny Yule, G. (1920). "An Inquiry into the Nature of Frequency Distributions Representative of Multiple Happenings with Particular Reference to the Occurrence of Multiple Attacks of Disease or of Repeated Accidents". Journal of the Royal Statistical Society 83: 255–279. JSTOR 2341080.
- Edgar L. Collis and Major Greenwood The health of the industrial worker. 1921
- Major Greenwood The natural duration of cancer. London, England: His Majesty’s Stationery Office, Reports on Public Health and Medical Subjects, No. 33. 1926
- Major Greenwood Epidemics and crowd-diseases: an introduction to the study of epidemiology. 1935
- Major Greenwood Medical statistics from Graunt to Farr: the Fitzpatrick lectures for the years 1941 and 1943. 1948
- Hogben, L. (1950). "Major Greenwood. 1880-1949". Obituary Notices of Fellows of the Royal Society 7 (19): 138. doi:10.1098/rsbm.1950.0010.
- "Buchanan archive winners 1957 – 1897". The Royal Society. Retrieved 22 March 2011.
- "Royal Statistical Society Presidents". Royal Statistical Society. Retrieved 6 August 2010.
- Greenwood, Major (1926). "The natural duration of cancer". Reports on Public Health and Medical Subjects (London: Her Majesty's Stationery Office) 33: 1–26.
- Kaplan, Edward L.; Meier, Paul (1958). "Nonparametric estimation from incomplete observations". J. Amer. Statist. Assn. 53 (282): 457–481. JSTOR 2281868.
- Kaplan, Edward L. in a retrospective on the seminal paper in "This week's citation classic". Current Contents 24, 14 (1983). Available from UPenn as PDF.
- Greenwood, Major (1946). "The Statistical Study of Infectious Diseases". Journal of the Royal Statistical Society 109 (2): 85–110. doi:10.2307/2981176.
- Riley, M. C.; Clare, A.; King, R. D. (2007). "Locational distribution of gene functional classes in Arabidopsis thaliana". BMC Bioinformatics 8: 112. doi:10.1186/1471-2105-8-112.
- Royal Society Certificate of Election and Candidature
- A. B. H.; William Butler (1949) "Obituary: Major Greenwood", Journal of the Royal Statistical Society. Series A (General), 112, 487–489.
- McKinlay, P. L. (1951). "Major Greenwood, 1880-1949". Biometrika 38 (1–2): 1–3. PMID 14848107.
- Anne Hardy; Eileen Magnello (2002) "Statistical methods in epidemiology: Karl Pearson, Ronald Ross, Major Greenwood and Austin Bradford Hill", 1900–1945 Soz Praventiv Med; 47(2): 80–89.
- Farewell, V.; Johnson, T.; Armitage, P. (2006). "'A memorandum on the Present Position and Prospects of Medical Statistics and Epidemiology' by Major Greenwood". Statistics in Medicine 25 (13): 2161–77. doi:10.1002/sim.2608. PMID 16755605.
- J. Rosser Matthews (1995) Quantification and the Quest for Medical Certainty, Princeton, Princeton University Press.
- "Greenwood, Major". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/51797. (Subscription or UK public library membership required.)