CiteScore and Nursing Journals
Marilyn H. Oermann and Jamie L. Conklin
Nurse Author & Editor, 2017, 27(2), 3
The journal impact factor (IF) has been a leading metric in determining the quality of academic journals. The IF of a journal is used by authors for selecting a journal for their manuscript and by editors, publishers, and others to indicate the quality of a journal. Impact factors, however, were never intended for choosing a journal in which to publish or as a metric for determining journal quality. The IF was designed originally as a measure to help librarians make decisions about journal collections (Polit & Northam, 2011).
The IF of a journal is a measure of how many times articles in a journal indexed in the Web of Science database are cited within a 2-year period in other journals in this same database. Only a limited number of nursing journals, however, are indexed in this database to have an IF. Impact factors are reported in the Journal Citation Reports, and nursing journals are included in both the Science Citation Index Expanded (SCIE) and the Social Sciences Citation Index (SSCI). There are only 116 nursing journals in the SCIE and 114 in the SSCI, but there are dozens of other nursing journals. More importantly, many nursing journals target clinicians, educators, managers, and nurses in other roles who use the nursing literature to keep up-to-date with new ideas and gain new knowledge to improve their practice. These readers are not inclined to then write manuscripts that cite the articles they read. As a result, many nursing journals have low IFs, which is not an indicator of their quality but reflects the journal mission and readers, and types of articles published in the journal.
In determining the IF, only citable items are considered. Citable items are research reports, scholarly articles, and other types of original manuscripts in the journal. Editorials, letters to the editor, news items, and similar types of short papers are not citable items. The IF is a ratio of the number of times articles in a journal are cited in other indexed journals within a 2-year period based on the total number of citable items within that same time period. The number of times articles in a journal are cited is the numerator, and the denominator is number of citable items.
In December 2016, Elsevier introduced a new metric to compete with IF: CiteScore (CS). CiteScore is the average number of citations to a journal over a 3-year period compared to a 2-year time frame with IF. CiteScore provides a longer period of time for citations to accumulate. The CS of a journal in 2015 is the number of citations the journal received in 2015 divided by the number of documents published in journals indexed in the Scopus database in the prior 3 years (Zijlstra & McCullough, 2016). CiteScore is based on journals in Scopus whereas IF is based on journals in Web of Science. The Scopus database includes twice as many journals as Web of Science.
A second major difference is that CS includes all types of documents, not only research reports, scholarly articles, and other types of substantive articles. CiteScore also includes editorials, letters to the editor, news items, notes, and conference papers, among others (Zijlstra & McCullough, 2016). This is a significant difference between the two metrics, and it can lead to much different scores. Some high impact journals such as The New England Journal of Medicine, Nature, and Science have a lower CS because it counts all of the documents in the journal as citable (Van Noorden, 2016). Editorials, letters to the editor, news items, and so on are not as frequently cited as substantive articles, resulting in a lower CS.
Esposito (2017) pointed out another difference between these two scores: the possibility of a conflict of interest with CS that is not present with IF. The IF is produced by Clarivate Analytics (formerly Thompson Reuters), which is not a publisher. In contrast, CS is produced by Elsevier, and the metric is calculated based on journals in Elsevier’s Scopus database. Web of Science has a clear vetting process for journals to be included in the database, but CS indexes all journals in Scopus. The Table lists other differences between IF and CS.
Table. Comparison between Journal Impact Factor and CiteScore
One advantage of CS is that it is freely available in Scopus. It also is easy to access. There are two main places to access CS metrics (Elsevier, 2016). You can go to the Sources page on Scopus.com. Once there, click title and enter the name of the journal under Search. You also can go to Journal Metrics. You can search by subject areas. Nursing as a subject area includes 627 titles divided into 24 subcategories. These subject areas and subcategories are based on the Scopus journal classification system, which has been shown to be too lenient in its category assignments (Wang & Waltman, 2016). For example, the first 25 journals listed within the Nursing subject area are mainly nutrition journals and do not include any nursing journals. The 24 subcategories are not the typical ways in which nursing journals are organized. For example, one subject area is called Assessment and Diagnosis, and the list of nursing journals includes the Journal of Hospital Medicine and Blood Pressure Monitoring, and some nursing journals. There is an LVN and LPN category that includes speech and language journals and a few nursing journals such as Nursing Made Incredibly Easy and Clinical Nurse Specialist.
There are 91 journals in the General Nursing subject area, and this category includes a more typical list of nursing journals such as the International Journal of Nursing Studies, Journal of Nursing Scholarship, and Journal of Advanced Nursing. However, the top “nursing journal” in General Nursing is the Journal of the American Medical Directors Association, and there are other non-nursing journals in this group. Davis (2016) commented that some high profile journals are miscategorized, such as the Annual Review of Plant Biology being ranked fourth in General Medicine Journals.
We searched for nursing journals in different categories and found some unusual classifications. Nurse Educator, for example, is listed in the Review and Exam Preparation subject area, not in General Nursing with the other nursing education journals.
Another Metric but the Same Issue
The issue remains the same: citations are not a measure of journal quality regardless of whether only substantive articles are counted or if all documents are counted in the metric. We do not need a new measure of journal impact that relies on citations. Journal metrics tell us nothing about the quality of a research study published in a journal or quality of a non-databased article that improves the quality of care. Fenner (2013) suggested that citation based journal metrics do not capture impact in fields that apply research such as clinical medicine. The same is true for nursing. We should focus on the quality and impact of articles, not journals. Who reads our articles, cites them in other papers, and uses them to guide their research, clinical practice, and teaching? Other article-level metrics such as number of downloads or views of an article can tell us more about quality and impact than citations of a journal.
- Davis, P. (2016, Dec 12). CiteScore–Flawed but still a game changer. The Scholarly Kitchen. https://scholarlykitchen.sspnet.org/2016/12/12/citescore-flawed-but-still-a-game-changer/
- Elsevier. (2016). Scopus. Available at https://blog.scopus.com/posts/how-to-explore-compare-and-track-journal-citation-impact-with-citescore-metrics. Retrieved March 10, 2017.
- Esposito, J. (2017, Jan 11). The measure of all things: Some notes on CiteScore. The Scholarly Kitchen. https://scholarlykitchen.sspnet.org/2017/01/11/the-measure-of-all-things-some-notes-on-citescore/.
- Fenner, M. (2013). What can article-level metrics do for you? PLoS Biology, 11(10), e1001687. http://doi.org/10.1371/journal.pbio.1001687
- Polit, D. F., & Northam, S. (2011). Impact factors in nursing journals. Nursing Outlook, 59(1), 18–28. https://doi.org/10.1016/j.outlook.2010.11.001
- Van Noorden, R. (2016). Controversial impact factor gets a heavyweight rival. Nature, 540, 325-326. doi:10.1038/nature.2016.21131
- Wang, Q., & Waltman, L. (2016). Large-scale analysis of the accuracy of the journal classification systems of Web of Science and Scopus. Journal of Informetrics, 10(2), 347-364. doi:10.1016/j.joi.2016.02.003
- Zijlstra, H., & McCullough, R. (2016). CiteScore: a new metric to help you track journal performance and make decisions. Available at https://www.elsevier.com/editors-update/story/journal-metrics/citescore-a-new-metric-to-help-you-choose-the-right-journal. Retrieved March 10, 2017.
About the Authors
Marilyn H. Oermann, PhD, RN, ANEF, FAAN, is Thelma M. Ingles Professor of Nursing, Duke University School of Nursing, Durham, North Carolina, USA. She is Editor of Nurse Educator and the Journal of Nursing Care Quality. Email: firstname.lastname@example.org
Jamie L. Conklin, MSLIS, is Research & Education Librarian and Liaison to the School of Nursing, Duke University Medical Center Library & Archives, Durham, North Carolina, USA. Email: email@example.com
Copyright 2017: The Authors. May not be reproduced without permission.
Journal Complication Copyright 2017: John Wiley and Son Ltd