Skip to Main Content

Impact Metrics : Altmetrics

How are altmetrics typically used?

Image of article with a ribbon

Altmetrics (aka alternative metrics) attempt to measure the social attention an individual publication receives. They are typically used to supplement traditional impact metrics (e.g., citation counts), and are particularly useful in attempting to quantify the impact of works that have the goal of public engagement or outreach.

Altmetrics are an article level metric.

How are altmetrics calculated?

The term "altmetrics" encompasses many different metrics types, which differ depending on which source you use. The two most common sources of altmetrics data are Altmetric and PlumX Metrics. Some of the different altmetrics types from these platforms and their calculations are included below.

Altmetrics types in the Altmetric platform Altmetric logo

  • Attention Score: This score indicates the total attention received by a publication. Attention scores are calculated by an algorithm, which quantifies a publication's mentions on sources such as social media sites (e.,g., Facebook or Twitter), blogs, news outlets, policy sources, and Wikipedia pages (in addition to other sources). It also factors in citation counts (via Dimensions and Web of Science), and readers in Mendeley and CiteULike. The sources of the publication's mentions are weighted, meaning that some source mentions are of "higher value" than other sources (e.g., a publication's mention in a news article will be weighted higher than a Twitter mention). For additional information on how Attention Scores are calculated, see Altmetric's information page on Attention Scores.

  • Output Rankings (Attention Score in Context): These metrics, which include both numbered rankings and percentages, rank the article's attention score (see above) in relation to all research outputs in the Altmetric platform, all outputs from the journal in which the article was published, all outputs of a similar age to the article, and all outputs of similar age from the journal in which the article was published.

  • Mentioned by: These provide counts of the number of times an article has been mentioned in sources such as news outlets, blogs, policy sources, social media outlets (e.g., Twitter), and Wikipedia (among other sources).

  • Citations: This is the number of times an article has been cited according to Dimensions and Web of Science data.

  • Readers on: These provide counts of the number of Mendeley and CiteULike users who have the article saved on Mendeley or CiteULike.

Note: For the full list of the Altmetric platform's data sources, see Altmetric's Sources of Attention page.

Altmetrics types in the PlumX Metrics platform Plum Analytics Logo

  • Citations: This is the number of times an article has been cited according to various sources, including both traditional indexes (e.g., Scopus) and sources that indicate societal impact. For a full list of citation sources, see PlumX Metrics' Citation Metrics page.

  • Usage: This number indicates the number of clicks, downloads, views, library holdings, video plays, and other indications of usage an article has received. For all usage types, see PlumX Metrics' Usage page.

  • Captures: This includes the number of times an article has been bookmarked, times an article has been added to someone's favorites, readers (e.g., Mendeley users that have saved the article in Mendeley), subscribers, and other indications of intentions to return to the article. For all capture types, see PlumX Metric's Captures page.

  • Mentions: This number includes the number of times an article has been mentioned in sources such as blog posts, comments, reviews, Wikipedia references, news media, and other mentions that indicate public engagement. For all mention types, see PlumX Metric's Mentions page.

  • Social Media: This number includes Facebook likes, comments, shares, and other indicators of social media attention for an article. For all social media metrics types, see PlumX Metric's Social Media page.

Note: In the upper-right hand side of every PlumX Metrics page you will see "Metric Options" with the option for 1 year or 3 year. If you click the 1 year or 3 year option, the page will show the metrics as percentiles of how the article compares to other articles published by the same journal within the selected time period.

Where can I find an article's altmetrics?

You can find an article's altmetrics from Altmetric by using the Altmetric Bookmarklet tool, and you can find an article's altmetrics from PlumX Metrics by searching for an article in Scopus.

Finding an article's altmetrics using the Altmetric Bookmarklet tool Altmetric logo

  1. Click here to sign up for the Altmetric Bookmarklet tool
  2. After signing up, follow the instructions to add the Altmetric Bookmarklet to your bookmarks
  3. Once you have the tool added to your bookmarks, search for the article in a database (e.g., PubMed or Scopus) or on the journal's website
  4. Click the title of the article from your results page
  5. Click the Altmetric Bookmarklet
  6. You should see the Altmetric menu appear in the upper right-hand corner of your screen. Click "Click for more details" to go to the Altmetric page for the article

Note: The Altmetric Bookmarklet tool may not work on all journal websites or databases.

Finding an article's altmetrics using Scopus Scopus logo Plum Analytics Logo

  1. Go to Scopus
  2. Enter the title of the article into the search bar
  3. Look for your article in the results list
  4. Scroll down until you see "Metrics" towards the middle of the page
  5. Click "Metrics"
  6. This should display Scopus impact metrics as well as PlumX Metrics. Click "View PlumX details" to go to the article's PlumX Metrics page

What are some limitations of altmetrics as a metric?

Like any impact metric, altmetrics have their limitations. Some of the these limitations include:

  • Inconsistencies between data sources (e.g., an article's "Mentioned by" and "Mentions" may be different in Altmetric vs PlumX Metrics, respectively)
  • Lack of transparency in metric calculations
  • Algorithms may be subject to error
  • Not all attention is "good" attention
  • Does not take into account the quality of the article (e.g., a poorly conducted study may go viral on social media)
  • What qualifies as "good" altmetric values will differ by field.
  • Bias favoring newer articles, especially those published after Altmetric and PlumX Metrics were created (2011 and 2015, respectively)
  • Bias favoring controversial topics
  • Lack of standardization between data sources
  • Like all impact metrics, vulnerable to gamification

Where can I learn more?

For a general overview of altmetrics, see:

  • Priem J, Taraborelli P, Groth P, Neylon C. Altmetrics: A manifesto. Altmetrics. 2010. Accessed April 8, 2022.

For an overview of the Altmetric and PlumX Metrics platforms, respectively, see:

  • What are altmetrics? Altmetric. Accessed April 8, 2022.

  • About PlumX Metrics. Plum Analytics. Accessed April 8, 2022.

For an overview of different metrics types, including altmetrics, see:

For a review into the association between Altmetric's Attention Score and citation counts, see:

For a look into how altmetrics can be gamed, see:

For examples of how altmetrics can be used, see:

  • Altmetrics (subject guide). University of Pittsburgh Library System. Accessed April 8, 2022.