Altmetrics are alternative metrics to the more traditional methods of measuring research impact, like h-index and journal impact factor. Altmetrics are often metrics about articles but also include metrics for other types of research products, like presentations and data sets.
Limitations of bibliometrics can include:
- Quality: high citation counts may not indicate quality. An article may be cited frequently because other authors are refuting its findings.
- Discipline variation: some research fields cite papers more than others. For example, in medicine and health there is a strong culture of citing and using other studies to validate findings.
- Level of researcher experience: some metrics give experienced researchers an advantage over early career researchers. It is important not to compare researchers who are at different stages of their career.
- Incomplete data: the tools used to gather bibliometric data do not cover all research areas or index all publications. The results will vary depending on the tool you use.
The Leiden Manifesto, published in Nature on April 23, 2015, was developed by Diana Hicks, professor of public policy at the Georgia Institute of Technology, Atlanta, Georgia, USA; Peter Wouters, professor of scientometrics; Ludo Waltman, researcher; Sarah de Rijcke, assistant professor at the Centre for Science and Technology Studies, Leiden University, the Netherlands; and Ismael Rafols, science-policy researcher at the Spanish National Research Council and the Polytechnic University of Valencia, Spain.
The 10 principles of the Leiden Manifesto about evaluating research are: