Author-level metrics are essentially the accumulation of output-level metrics. The H-Index, which many researchers are probably familiar with, can be retrieved in Web of Science and Google Scholar.
What is an H-Index and how is it calculated?
The H-Index is a metric based on the number of publications (productivity) and their times cited. It is where the number of papers and citations/paper would intersect on a plot.
If a researcher has 10 papers that have each been cited at least 10 times, the H-Index equals 10. If 9 of those papers were cited 25 or more times, the H-Index is still 10 if the 10th paper has only been cited 10 times. Once that article is cited 11 times, the researcher's H-Index goes up to 11.
What else do I need to know about the H-Index?
There is no single H-Index value.
Because the H-Index is based on publications and citations, Google Scholar and Web of Science will give you different values for the same researcher. If cited articles are missing from the list, or there are included articles that should not be there, these will impact the H-Index. And if the researcher does not have a Google Scholar Profile, then no H-Index.
Use caution when comparing researchers.
The H-Index is very much based on journal publications and citations, so the same caveats about comparing researchers across disciplines apply. In a discipline where books are a principal research output, fewer publications will mean lower H-Indicies. The H-Index is also a function of longevity; researchers 20 or more years in the field will have a higher H-Index than early career researchers in the same field
Where can I find an H-Index in Web of Science?
From the Web of Science search results screen, use Create Citation Report to get an H-Index for that set of papers. The H-Index here is generated from whatever.papers come up in the search, even a topic search.
To ensure that you are basing the H-Index on all of your papers (and only your papers), you can set up a ResearcherID profile through Web of Science to curate your list of publications and track the citation metrics. Again, this will still only track citing articles, conference papers, and books indexed in Web of Science.
Where can I find an H-Index in Google Scholar?
The H-Index can be found on the author's Google Scholar Profile page. It is based on what papers and other sources are included in the profile, and the citing sources covered in Google Scholar.. If there is no Profile, then no H-Index. It cannot be generated from search results like Web of Science.
You also get an i10-index, which is the number of papers that have been cited at least 10 times.