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1 correction found
A full index of the entire scientific literature.
Google Scholar is not a complete index of all scientific literature. Google itself says coverage is not guaranteed and some content may be excluded, and research has found important literature that Google Scholar misses.
Full reasoning
This overstates Google Scholar’s coverage.
Google Scholar’s own help page says that while it tries to be comprehensive, it “isn't possible to guarantee uninterrupted coverage of any particular source.” It also says some material “may or may not be included,” and that documents on sites unavailable to Google’s crawlers or behind certain access barriers are not included.
That directly contradicts the idea that Google Scholar is a full index of the entire scientific literature.
Independent research also finds that Google Scholar is incomplete in practice. A 2015 study in PLOS ONE concluded that Google Scholar “should not be used alone for systematic review searches” and reported that it missed some important literature in five of six case studies.
So Google Scholar is broad and useful, but it is not a complete index of all scientific literature.
2 sources
- Google Scholar Search Help
While we try to be comprehensive, it isn't possible to guarantee uninterrupted coverage of any particular source... Shorter articles, such as book reviews, news sections, editorials, announcements and letters, may or may not be included... Website URLs that aren't available to our search robots... are, obviously, not included either.
- The Role of Google Scholar in Evidence Reviews and Its Applicability to Grey Literature Searching
Our findings showed moderate/poor overlap... and that GS missed some important literature in five of six case studies... We conclude that whilst Google Scholar can find much grey literature and specific, known studies, it should not be used alone for systematic review searches.