From impact factors to Altmetrics: What numbers are important in publishing your paper?

Abstract

The volume of published research articles has increased exponentially over the past number of years, especially since many journals have transitioned to online open (free) access journal articles only. For this reason, it is important that academics, clinicians and researchers can quantify the impact and quality of the articles they are reading and publishing.1 It can become challenging to keep up to date with all of the terminology used to capture article and journal metrics. In this editorial we will present an overview of traditional metrics and newer, alternative metrics (Altmetrics) of article success and impact. One metric commonly used is the Journal Impact Factor (JIF). The JIF is calculated by Clarivate Analytics, a company that uses intelligence to provide data to make informed decisions and plans. The formula to calculate JIF is the total number of citations received by the journal in that year for articles published over the previous 2 years divided by the total number of citable items published by the journal in that 2-year period. The JIF score is a measure of journal impact; however, it has also traditionally been considered to be the most accurate measure of an author's impact and influence. Having high-impact factor publications has been an integral component of securing academic tenure positions and promotions, as well as research funding grants.1 There are advantages and disadvantages to using JIF. Advantages include simplicity in calculating JIF and that it is widely used across the world so many researchers and funding agencies are familiar with this metric. There are limitations to be aware of with JIF, one of which is that not all journals are included with many non-English language journals being excluded, as well as the inclusion of self-citations.2 Despite these limitations, JIF is still considered to be an important metric used by researchers when deciding where to publish. Many researchers will want to publish their work in the journal with the highest JIF in their field. However, having a manuscript accepted in such a journal is influenced by many factors, including the quality of the manuscript, the reviewers’ comments and ultimately the editors’ decision. CiteScore is another metric used by academics and researchers, and this is a measure of the citation impact of an article. CiteScore is based on the number of citations received over a 3-year period and is calculated by Scopus, a citation database. For many academic researchers, the CiteScore of a journal is important because it provides a transparent way of assessing the quality and impact of journals. Editors of journals usually observe the CiteScore of their journal annually to demonstrate the performance and quality of their journal. The standardized formula of the CiteScore is accepted worldwide and can be a transparent benchmarking tool. Editors of journals can use this score to make strategic decisions to increase the quality and impact of their journals. Also, universities, academic institutions, and research funding agencies are increasingly using CiteScore as a quality indicator for individual researchers. In some countries and institutions, these metrics can make or break your career when progressing on the academic ladder. However, this does not affect everyone because the requirements and assessment of academic progression vary between countries and institutions. Thus, check out your local requirements for how and what metrics are important if you are progressing in a clinical academic career. One other traditional journal metric is the H-index. The H-index is the most widely used measure of an author's level of productivity and impact, based on the number of publications and citations they have.3, 4 H-index are therefore considered by many to be measures of quantity and quality. One point to consider with the H-index that has been highlighted is the challenge of comparing researchers during different stages of their careers. It has been suggested that there is a correlation between the age of a researcher and their H-index.5 Some researchers have suggested that early career researchers are at a disadvantage when it comes to H-index. Senior or late stage career researchers will often have a higher H-index than early-mid career researchers simply because of the fact that they have had more time to publish.6 Altmetrics, also known as alternative metrics, are often used to measure the impact of research articles and outputs. They are usually used as an adjunct to traditional journal metrics (JIF, CiteScore, and H-index). In today's data-driven world, social media has become a platform to disseminate research to the wider scientific community.7 Twitter and LinkedIn are probably the most used social media platforms to share research findings, and some researchers have demonstrated that there is a correlation between the number of tweets an article has and the number of article citations.8 Public engagement with research has traditionally been difficult to measure. However, with Altmetrics, this has become easier to determine. Altmetric allows us to quantify public engagement with research outputs.9 This is important to capture because, typically, the general public will not be citing your work, but they may be engaging with research articles online in another way through blog posts, and so forth. Altmetrics compiles data from thousands of online sources, including social media (Twitter, Facebook, etc.), traditional mainstream media (online newspaper articles), blogs, and online reference managers. The most commonly used platform to capture alternative metrics is Altmetric.com. Altmetric measures the impact of research outputs through the Altmetric Attention Score (AAS). Like traditional metrics, the higher the number, the better. In Figure 1, we present the articles with the highest AAS score published in Nursing in Critical Care. As can be seen, each article is accompanied by a donut-shaped badge comprised of different colours. Each colour signifies a different source of attention; specifically, Twitter and LinkedIn are blue, Blogs are yellow, News outlets are red, Facebook is dark blue, Pinterest is amber, Google+ is light purple, policy documents are dark purple, and so forth. When an Altmetric badge is clicked, this allows you to see who is talking about your research, where they are in the world, and what they are saying. The article with the highest AAS published in Nursing in Critical Care journal can be seen in Figure 2.10 As illustrated in Figure 2, the source of online attention and geographical location can be easily visualized. Altmetrics are becoming increasingly recognized as a reliable indicator of article reach and success. Many funding agencies are now looking at Altmetrics to provide additional information about a research article. Universities are also now including Altmetrics in their data repositories. It has been demonstrated in other areas of health care that Altmetric scores directly correlate with article citations. This suggests that the Altmetric score and conventional bibliometrics can be treated as complementary metrics.11 To conclude, Altmetrics are a useful tool that can be used to measure the impact of research outputs. Altmetrics are not designed to replace traditional journal metrics, and they should be used to complement traditional journal metrics. Traditional journal metrics have been subject to criticism for several reasons. Nonetheless, they influence where researchers publish and where students are encouraged to submit. Many PhD students, for example, are encouraged to ‘shoot for the stars’ or ‘aim high’ and generally speaking, this advice tends to refer to the submission of articles to journals with high-ranking metrics, particularly JIF. However, there is no single traditional metric that can accurately measure the impact of research outputs.12 The data that support the findings of this study are available from the corresponding author upon reasonable request.