Top 10 scientists in clinical medicine based on total citations

	Scientist	Papers	Citations	Citations per paper
1	Walter C. Willett (epidemiology) Harvard University, Boston, MA	553	28,393	51.34
2	Meir J. Stampfer (epidemiology) Harvard University, Boston, MA	338	24,494	72.47
3	Paul M. Ridker (epidemiology) Harvard University, Boston, MA	237	24,072	101.57
4	Salim Yusuf (cardiology) McMaster University, Hamilton, Canada	7	23,280	84.04
5	Daniel Levy (cardiology) NHLBI and Boston University, MA	259	22,644	87.43
6	Rory Collins (epidemiology) University of Oxford	141	22,596	160.26
7	Richard Peto (epidemiology) University of Oxford	91	20,394	224.11
8	Bert Vogelstein (oncology) Johns Hopkins University, Baltimore, MD	99	20,319	205.24
9	JoAnn E. Manson (epidemiology) Harvard University, Boston, MA	316	20,098	63.60
10	Eric J. Topol (cardiology) The Scripps Research Institute, La Jolla, CA	429	20,083	46.81

The data above were extracted from the Essential Science Indicators database of Thomson Reuters covering the period 1 January 1998 through 30 June 2008. This database surveys only journal articles (original research reports and review articles) indexed by Thomson Reuters. Articles are assigned to a category based on the journals in which they were published and Thomson Reuters’ journal-to-category field-definition scheme. Both articles tabulated and citation counts to those articles are for the period indicated. Naturally, scientists publishing large numbers of papers have a greater likelihood of collecting more citations than scientists publishing fewer papers. This ranking is by total citations. For articles with multiple authors, each author receives full, not fractional, citation credit. Another ranking could be based on citations per paper, which reveals weighted impact. Essential Science Indicators lists authors ranked in the top 1 per cent for a field over a given period, based on total citations.

For these data, 15,858 authors are listed in the field of clinical medicine, meaning that a total of approximately 1,585,800 authors’ records were reviewed to obtain these results. As the data show, large-scale clinical studies, including the use of meta-analysis, were very influential in the past decade, represented by the work of nine of the ten authors listed, several specialising in epidemiology.

Exceptional is the research of Bert Vogelstein, whose studies of the molecular genetics of colon and other cancers have had a profound influence for many years. Note also his high citations per paper score. In fact, Professor Vogelstein has long been a chief pick of Thomson Reuters for a Nobel Prize in Physiology or Medicine.

For more information on Thomson Reuters’ Essential Science Indicators, see http://scientific.thomsonreuters.com/products/esi.