Top institutions in immunology based on impact

	Institution	Papers	Citations	Citations per paper
1	DNAX Research Institute USA	248	31,313	126.26
2	Japan Science and Technology Corporation Japan	391	30,240	77.34
3	Rockefeller University USA	494	,394	55.45
4	Osaka University Japan	1,018	46,617	45.79
5	Yale University USA	1,196	51,966	43.45
6	Kyoto University Japan	600	24,171	40.28
7	Brigham and Women’s Hospital USA	809	32,407	40.06
8	Stanford University USA	1,112	44,440	39.96
9	Washington University USA	1,037	39,853	38.43
10	Scripps Research Institute USA	906	34,732	38.34
11	National Institute of Allergy and Infectious Diseases USA	2,056	76,166	37.05
12	Massachusetts General Hospital USA	571	20,738	36.32
13	Harvard University USA	3,9	135,055	34.39
14	University of Texas Southwestern Medical Center USA	649	21,998	33.90
15	National Cancer Institute USA	1,623	54,811	33.77
16	University of Oxford UK	1,110	36,116	32.54
17	University of California, San Francisco USA	1,650	51,588	31.
18	University of Washington USA	1,647	50,687	30.78
19	University of California, San Diego USA	816	24,322	29.81
20	Emory University USA	962	28,177	29.29

The data above were extracted from the Essential Science Indicators database of Thomson Reuters. This database, currently covering the period January 1998 through June 2008, 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, institutions publishing large numbers of papers have a greater likelihood of collecting more citations than those publishing fewer papers. This ranking is by citations per paper (impact), among those institutions that have collected 20,000 or more citations in immunology. For papers with multiple institutional addresses, each institution receives full, not fractional, citation credit. Essential Science Indicators lists institutions ranked in the top 1 per cent for a field over a given period, based on total citations. For the current version, 282 institutions are listed in the field of immunology, meaning that a total of 56,400 institutions were reviewed to obtain these results. Of the 282, 39 institutions collected 20,000 or more citations. The ranking by impact seeks to reveal “heavy-hitters” based on per paper influence, not mere output. Notable here is the performance of Japanese institutions, which take three places in the top ten. For more information on Thomson Reuters’ Essential Science Indicators, see http://scientific.thomsonreuters.com/products/esi.