The Altmetric Attention Score: What Does It Mean and Why Should I Care?

You may have noticed a brightly colored donut with a central number when browsing the most cited or most read articles on our Toxicologic Pathology journal website (http://journals. sagepub.com/home/tpx, last accessed December 5, 2017) or when browsing articles associated with other websites. This measure of research impact is the Altmetric, short for alternative metrics, donut, and score. Briefly, it can provide information on web-driven scholarly interactions for the article you are interested in, including your own (Hirsch 2005; Melero 2015; Warren, Raison, and Dasgupta 2017). This score is intended to be complementary to traditional, citation-based metrics with most of the data derived from web-based social media feeds. Because it is updated in daily or real-time feeds, you can keep track of where articles are being shared and discussed among broader audiences. Compared to other measures of research impact, 2 main advantages of the Altmetric are the immediate availability of information on the reach and influence of an article and the ability to track how the attention changes over time. If you select the Altmetric icon located near the title of an article (see Elmore [2007] as example), you will see information on the title, journal, month/year of publication, digital object identifier number, PubMed ID, author(s), and abstract. The donut is located at the top of the left column of the article metrics website for any specific journal article (see https://sage .altmetric.com/details/817961 as example, last accessed December 5, 2017). It may be in one or many colors, with a central number, which is the score. Below the donut is a blue question mark that you may select with this pop-up information about the score: “the Altmetric attention score for a research output provides an indicator of the amount of attention that it has received. The score is derived from an automated algorithm and represents a weighted count of the amount of attention that is picked up for a research output.” There is also a link that will tell you how the scores are calculated (About the Altmetric and the Altmetric Attention Score). Briefly, the Altmetric score represents a weighted count of the amount of attention for a research output from a variety of sources (Table 1). The colors of the Altmetric donut each represent a different source of attention (medium blue for LinkedIn, yellow for blogs, red for mainstream media sources, purple for policy documents, etc.), and the amount of each color will change depending on which sources a research output has received attention from (Figure 1; the donut and Altmetric attention score). There are 3 main factors used to calculate the Altmetric score: volume (how many times the article is mentioned), sources (where the mentions come from), and authors (of each mention; Table 2). Information on how each factor might affect the score is provided on the Altmetric Support website (help.altmetric.com; outputs and sources) and reproduced in Table 2. Also in the left column of the article metrics website, you will see additional information if you select the “more . . . ” link such as where it ranks (in percentile) among all research outputs scored by Altmetric, how it ranks among outputs from this source, how the score ranks compared to outputs of the same age, and percentile among outputs of the same age and source. Below this information, you will see where the article has been mentioned (e.g., news outlets and blogs) and how many readers referenced the article on sites such as Mendeley and CiteULike. At the top of the article metrics website, you can see the summary information for the article as well as tabs for information on blogs, Twitter, Facebook, Wikipedia, Googleþ, and so on, depending on which websites and social media outlets the article has been mentioned on. At the bottom of the page, there are 3 selections: Twitter Demographics, Mendeley Readers, and Attention Score in Context. Below Twitter demographics and Mendeley Readers, you will see additional information on readership statistics such as geographics and demographics. The map provides a visual for the geographic information. If you choose Attention Score in Context, you will see number of all research outputs, number of outputs