Alternative metrics (or altmetrics) are an alternative to more traditional impact metrics with an emphasis on measuring the individual article rather than the journal in which it is published. They calculate an 'attention score' by counting data such as article views, downloads, blogs, mentions in social media (such as tweets, likes, shares, subscribers, followers) and news items. These metrics are generated by a variety of audiences including those not in academia, and are considered to be representative of the level of social engagement activity based on a work. One advantage of these metrics is speed. They are more immediate than traditional metrics using public APIs to gather data in days or weeks, rather than years.

Some of the limitations of alternative metrics include:

  • Potentially, they are simply a measure of popularity. 
  • The score does not directly tell you anything about the quality or impact of the paper. Some papers with high scores may simply be controversial and therefore have been discussed more than other papers. Altmetrics cannot differentiate between negative and positive cites.
  • More recent papers may have an advantage because of the uptake of social media in recent years and because papers are generally mentioned more at the time of publication.

Some alternative metric tools

  • maintain a cluster of servers that watch social media sites, newspapers, government policy documents and other sources for mentions of scholarly articles. They bring all the attention together to compile article level metrics. They offer a number of free services for individual researchers.  
  • Impact Story is an open-source, web-based tool that helps scientists explore and share the diverse impacts of all of their research —from journal articles, to blog posts, datasets, and software.
  • PlumX Metrics brings together appropriate research metrics for all types of scholarly research output and categorises them into 5 separate categories: Citations, Usage, Captures, Mentions and Social Media.  Policy citation data are provided by Overton.  

Alternative metrics serve as a supplement to traditional metrics. It is always a good idea to use a range of metrics appropriate to your discipline and relevant to the context in which they are being used.