PHILADELPHIA and LONDON - The Healthcare and Science business of Thomson Reuters announced yesterday the results of a study assessing influential research in bioterrorism from 1999 to 2008. The findings appear in the May/June issue of Science Watch (www.sciencewatch.com) and are based on more than 12,000 bioterrorism-related papers published in Thomson Reuters-indexed journals during this time period.

Science Watch ranked the top 25 institutions by both total citations and citation impact (average citations per paper). The United States accounts for 23 of the top 25 institutions in both total citations and citation impact. The U. S. Army took the top spot in total citations with an impressive 9,637 citations to its researchers' work. The U. S. Centers for Disease Control and Prevention ranked second with 6,912 citations, and Johns Hopkins University with 5,006 citations ranked third.

U. S. institutions also led the pack in citation impact, a measure of average citations per published paper. The Institute for Genomic Research had an impact of 62.64 and the New York City Department of Health had an impact of 57.06. Claiming the third spot was the Imperial College of London with an impact of 31.55.

The most cited bioterrorism paper was published in 2001, regarding the causative agent of plague, Yersinia pestis; this paper has been cited nearly 500 times. The second most cited paper, entitled "Anthrax," was published two years before anthrax-tainted mail killed five people in 2001; this paper has now been cited more than 400 times. The third most-cited paper, published in 1999 and garnering more than 375 citations, discusses the use of smallpox as a biological weapon.

For the complete rankings of total citations and citation impact in the bioterrorism field, as well as a rundown of the most cited individual bioterrorism researchers during the time period, visit ScienceWatch.com.