Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2013 Sep 12:2:74.
doi: 10.1186/2046-4053-2-74.

Bibliometrics of systematic reviews: analysis of citation rates and journal impact factors

Pamela Royle  1 , Ngianga-Bakwin Kandala, Katharine Barnard, Norman Waugh
Affiliations

Bibliometrics of systematic reviews: analysis of citation rates and journal impact factors

Pamela Royle et al. Syst Rev. .

Abstract

Background: Systematic reviews are important for informing clinical practice and health policy. The aim of this study was to examine the bibliometrics of systematic reviews and to determine the amount of variance in citations predicted by the journal impact factor (JIF) alone and combined with several other characteristics.

Methods: We conducted a bibliometric analysis of 1,261 systematic reviews published in 2008 and the citations to them in the Scopus database from 2008 to June 2012. Potential predictors of the citation impact of the reviews were examined using descriptive, univariate and multiple regression analysis.

Results: The mean number of citations per review over four years was 26.5 (SD ± 29.9) or 6.6 citations per review per year. The mean JIF of the journals in which the reviews were published was 4.3 (SD ± 4.2). We found that 17% of the reviews accounted for 50% of the total citations and 1.6% of the reviews were not cited. The number of authors was correlated with the number of citations (r = 0.215, P < 0.001). Higher numbers of citations were associated with the following characteristics: first author from the United States (36.5 citations), an ICD-10 chapter heading of Neoplasms (31.8 citations), type of intervention classified as Investigation, Diagnostics or Screening (34.7 citations) and having an international collaboration (32.1 citations). The JIF alone explained more than half of the variation in citations (R(2) = 0.59) in univariate analysis. Adjusting for both JIF and type of intervention increased the R2 value to 0.81. Fourteen percent of reviews published in the top quartile of JIFs (≥ 5.16) received citations in the bottom quartile (eight or fewer), whereas 9% of reviews published in the lowest JIF quartile (≤ 2.06) received citations in the top quartile (34 or more). Six percent of reviews in journals with no JIF were also in the first quartile of citations.

Conclusions: The JIF predicted over half of the variation in citations to the systematic reviews. However, the distribution of citations was markedly skewed. Some reviews in journals with low JIFs were well-cited and others in higher JIF journals received relatively few citations; hence the JIF did not accurately represent the number of citations to individual systematic reviews.

PubMed Disclaimer

References

    1. Bastian H, Glasziou P, Chalmers I. Seventy-five trials and eleven systematic reviews a day: How will we ever keep up? PLoS Med. 2010;7:e1000326. doi: 10.1371/journal.pmed.1000326. - DOI - PMC - PubMed
    1. The Thomson Reuters impact factor. [ http://wokinfo.com/essays/impact-factor/]
    1. Colledge L, de Moya-Anegón F, Guerrero-Bote V, López-Illescas C, El Aisati M, Moed HF. SJR and SNIP: two new journal metrics in Elsevier’s Scopus. Serials. 2010;23:215–221. doi: 10.1629/23215. - DOI
    1. JournalM3trics: research analytics redefined. Frequently asked questions. Amsterdam: Elsevier; 2011. [ http://www.journalmetrics.com/FAQs.pdf]
    1. Moed HF. Measuring contextual citation impact of scientific journals. J Informetr. 2010;4:265–277. doi: 10.1016/j.joi.2010.01.002. - DOI

LinkOut - more resources