Cited Reference Searching: What About Google Scholar?

Identifying publications that have cited an article of interest.

Google Scholar for Cited Reference Searching: Pros and Cons

Question: Who has cited this 2012 study on the effects of nighttime sleep duration on obesity gene expression?

Results: What did I find in Google Scholar that I didn't find in the other databases?

Pros: Access to Preprints of Scholarly Articles, Dissertations, and Reports

Google Scholar returned an "article ahead of print" in Advances in Nutrition. Because it wasn't yet published as part of a formal journal issue, it had not yet been indexed by Web of Science or PubMedCentral. When the article is formally published, it will be indexed by those databases. [It will be included in PubMedCentral because the research depended on NIH funding.] Google Scholar also returned a dissertation that wasn't in the other databases, reports from Robert Wood Johnson, a blog post, and several non-English language articles.

Cons: Inaccurate Results

Google Scholar also returned a 2008 report on obesity titled "F is for Fat: How Obesity Policies are Failing " from the Robert Wood Johnson Foundation. This could be interesting, but it does not in fact cite my article. The obesity report was written before my article was even published.

Resource	Number of citing publications	Type of citing publications	Accurate?	Complete?	Timeliness Rank

Web of Science	37	Articles, book chapter	Yes	No	2
PubMed Central	23	Articles	Yes	No	2
Google Scholar	80	Articles, book chapters, dissertations, preprints, reports, & blog posts.	No	No	1

[Searches conducted July 17, 2020.]

Bottom Line

1. Google Scholar is great for finding citing references that may not be available in literature databases.

2. Google Scholar might not be an acceptable source for citation metrics and author impact factors for scholarly purposes, such as promotion & tenure.

Google Is Not a Database

Unlike the other sources for cited reference searching,

Google Scholar is an internet search engine, not an organized database.
The scope of Google Scholar is not limited to scholarly publications.
The journal titles and time frame of coverage are not specified in Google Scholar.
Google Scholar has not been structured and indexed by humans.
Google Scholar retrieves publications that are not included in standard bibliographic databases.
Google Scholar may retrieve the same publication in multiple locations: on research lab websites, in patents, in PowerPoint presentations, etc.

No citation metric tool offers an exact measure of research impact. Still, it's important to remember that the number of citing publications listed by Google Scholar is likely to be an inflated number. If you're documenting the citation count of an article or h-index of an author, it's important to specify that the source of those metrics is Google Scholar.