Articulo Investigacion

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N u r s O u t l o o k 5 9 ( 2 0 1 1 ) 1 8 e2 8

www.nursingoutlook.org

Impact factors in nursing journals
Denise F. Polit, PhD, FAANa,b,*, Sally Northam, RN, PhDc
a

b

Humanalysis, Inc., Saratoga Springs, NY
Research Centre for Clinical & Community Practice Innovation, Griffith University, Gold Coast, Australia
c
The University of Texasat Tyler College of Nursing and Health Sciences, Tyler, TX

article info

abstract

Article history:
Received 28 June 2010
Revised 15 September 2010
Accepted 4 November 2010

Journal impact factors (IFs), a measure of citation frequency, are published
annually in Journal Citation Reports (JCR). Journal IFs, although controversial
because of the uses to which they have been put inacademic arenas, remain
a metric about which nurses should be informed. This paper discusses key
issues in the controversy, explains how IFs are computed, and presents
historical and 2009 IF data for nursing journals. The number of nursing journals indexed in JCR has grown from 35 in 2004 to 74 in 2009. The journals
currently indexed are diverse in terms of focus (practice vs research), specialtyareas, and country of publication. The median IF score for nursing journals
(0.91 in 2009) is similar to that for several other health care categories. Given
the controversies surrounding IFs, it may be useful for nurses to play a more
active role in furthering the debate by undertaking research relating to IFs,
including studies of how they affect nurses’ scholarly pursuits and publicationdecisions.

Key words:
Bibliometrics
Citation rate
Communication
Impact factor
Nursing journal
Professional issues
Publishing

Cite this article: Polit, D. F., & Northam, S. (2011, FEBRUARY). Impact factors in nursing journals. Nursing
Outlook, 59(1), 18-28. doi:10.1016/j.outlook.2010.11.001.

Journal impact factors (IFs) are scores based on citation
analysis that are calculatedannually through
Thomson-Reuters’ Institute of Scientific Information
(ISI) and published in the Journal Citation Reports (JCR)
each June for the preceding year.1 Journal IFs are one of
many available metrics of journal performance that
involve an analysis of citation frequencydthat is,
counts of how frequently articles in the journal are
cited by other articles in the subsequent 2-year period.Specific details about the calculation of IFs are
described later in this paper.
IFs have been criticized by many scholars and
researchers, both on conceptual and technical

grounds.2-6 Yet, IFs remain widely-used indicators that
are difficult to ignore by nurses in academia because of
their increased use by those on appointment, promotion, tenure committees,3,7,8 by funding agencies,5,9 byuniversity administrators making resource allocation
decisions to departments,3,10 and by governments
undertaking reviews of the overall impact of research
outputs, such as occurs in Australia, England, and some
Asian countries.2,9,11,12 Consequently, nurse researchers, scholars, and editors need to have a firm understanding of how this bibliometric index works, what IFs
mean, and what theirlimitations are. The purposes of
this article are to (1) explain IFs and some related
indexes; (2) describe the major concerns that have been

* Corresponding author: Dr. Denise F. Polit, Humanalysis, Inc., 75 Clinton Street, Saratoga Springs, NY 12866.
E-mail address: dpolit@rocketmail.com (D.F. Polit).
0029-6554/$ - see front matter Ó 2011 Elsevier Inc. All rights reserved.doi:10.1016/j.outlook.2010.11.001

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expressed about IFs; (3) discuss how nursing journals
have fared in the IF system, both historically and
compared with other academic disciplines; and (4)
present IFs and other metrics of nursing journals for the
journal year 2009, the most recent year available.

Background
The idea of an IF was first described by...