Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

The History and Meaning of the Journal Impact Factor

The History and Meaning of the Journal Impact Factor COMMENTARY The History and Meaning of the Journal Impact Factor duces the number of journals with the identical impact rank. Eugene Garfield, PhD However, it matters very little whether, for example, the im- pact of JAMA is quoted as 24.8 rather than 24.831. FIRST MENTIONED THE IDEA OF AN IMPACT FACTOR IN A journal’s impact factor is based on 2 elements: the nu- Science in 1955. With support from the National merator, which is the number of citations in the current year Institutes of Health, the experimental Genetics Citation to items published in the previous 2 years, and the denomi- IIndex was published, and that led to the 1961 publica- nator, which is the number of substantive articles and re- tion of the Science Citation Index. Irving H. Sher and I cre- views published in the same 2 years. The impact factor could ated the journal impact factor to help select additional just as easily be based on the previous year’s articles alone, source journals. To do this we simply re-sorted the author which would give even greater weight to rapidly changing citation index into the journal citation index. From this fields. An impact factor could also take into http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png JAMA American Medical Association

The History and Meaning of the Journal Impact Factor

JAMA , Volume 295 (1) – Jan 4, 2006

Loading next page...
 
/lp/american-medical-association/the-history-and-meaning-of-the-journal-impact-factor-6ZVj7wQfhb
Publisher
American Medical Association
Copyright
Copyright 2006 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.
ISSN
0098-7484
eISSN
1538-3598
DOI
10.1001/jama.295.1.90
pmid
16391221
Publisher site
See Article on Publisher Site

Abstract

COMMENTARY The History and Meaning of the Journal Impact Factor duces the number of journals with the identical impact rank. Eugene Garfield, PhD However, it matters very little whether, for example, the im- pact of JAMA is quoted as 24.8 rather than 24.831. FIRST MENTIONED THE IDEA OF AN IMPACT FACTOR IN A journal’s impact factor is based on 2 elements: the nu- Science in 1955. With support from the National merator, which is the number of citations in the current year Institutes of Health, the experimental Genetics Citation to items published in the previous 2 years, and the denomi- IIndex was published, and that led to the 1961 publica- nator, which is the number of substantive articles and re- tion of the Science Citation Index. Irving H. Sher and I cre- views published in the same 2 years. The impact factor could ated the journal impact factor to help select additional just as easily be based on the previous year’s articles alone, source journals. To do this we simply re-sorted the author which would give even greater weight to rapidly changing citation index into the journal citation index. From this fields. An impact factor could also take into

Journal

JAMAAmerican Medical Association

Published: Jan 4, 2006

References