Altmetrics

In scholarly and scientific publishing, altmetrics (stands for "alternative metrics") are non-traditional bibliometrics proposed as an alternative or complement to more traditional citation impact metrics, such as impact factor and h-index. The term altmetrics was proposed in 2010, as a generalization of article level metrics, and has its roots in the #altmetrics hashtag. Although altmetrics are often thought of as metrics about articles, they can be applied to people, journals, books, data sets, presentations, videos, source code repositories, web pages, etc.

Altmetrics use public APIs across platforms to gather data with open scripts and algorithms. Altmetrics did not originally cover citation counts, but calculate scholar impact based on diverse online research output, such as social media, online news media, online reference managers and so on. It demonstrates both the impact and the detailed composition of the impact. Altmetrics could be applied to research filter, promotion and tenure dossiers, grant applications and for ranking newly-published articles in academic search engines.

Over time, the diversity of sources mentioning, citing, or archiving articles has gone down. This happened because services ceased to exist, like Connotea, or because changes in API availability. For example, PlumX removed Twitter metrics in August 2023.

The development of web 2.0 has changed the research publication seeking and sharing within or outside the academy, but also provides new innovative constructs to measure the broad scientific impact of scholar work. Although the traditional metrics are useful, they might be insufficient to measure immediate and uncited impacts, especially outside the peer-review realm.

Projects such as ImpactStory, and various companies, including Altmetric, Plum Analytics and Overton are calculating altmetrics. Several publishers have started providing such information to readers, including BioMed Central, Public Library of Science (PLOS), Frontiers, Nature Publishing Group, and Elsevier. The NIHR Journals Library also includes altmetric data alongside its publications.

In 2008, the Journal of Medical Internet Research started to systematically collect tweets about its articles. Starting in March 2009, the Public Library of Science also introduced article-level metrics for all articles. Funders have started showing interest in alternative metrics, including the UK Medical Research Council. Altmetrics have been used in applications for promotion review by researchers. Furthermore, several universities, including the University of Pittsburgh are experimenting with altmetrics at an institute level.

However, it is also observed that an article needs little attention to jump to the upper quartile of ranked papers, suggesting that not enough sources of altmetrics are currently available to give a balanced picture of impact for the majority of papers.

Important in determining the relative impact of a paper, a service that calculates altmetrics statistics needs a considerably sized knowledge base. The following table shows the number of artefacts, including papers, covered by services: