Google Scholar is the world’s largest and most-used academic search engine, yet it is increasingly becoming polluted with junk science, making it a potentially dangerous database for anyone doing serious research, from students to scientists.

The problem is that Google Scholar aims to be comprehensive, indexing articles from as many scholarly appearing journals as possible. On the surface, that goal seems noble, but a closer look reveals a major flaw in the strategy.

Because predatory publishers perform a fake or non-existent peer review, they have polluted the global scientific record with pseudo-science, a record that Google Scholar dutifully and perhaps blindly includes in its central index. Most predatory journals are included in Google Scholar. The database does not sufficiently screen for quality, in my opinion.

Google Scholar works well for known-item searches, for example, when you quickly need to locate a known article or a paper by a known author.

It performs poorly, on the other hand, at finding an article on a specific topic. It doesn’t use controlled vocabularies and includes junk science in its index. If you aren’t an expert, you are unable to separate out the junk science from the authentic science, and both are included one after another in Google Scholar search results. For those seeking the top scholarly literature on a given subject, the best resource is a focused, high-quality, curated database licensed by a library.

Junk Science

Predatory journals are also enabling the publication of much “activist science,” publishing articles that appear to be scientific but that could never pass peer review and be accepted and published in authentic journals. Activists publishing pseudo-scientific articles indexed in Google Scholar include:

Those promoting hypotheses that mainstream science has found to be false, such as claiming that vaccines are the etiology of autism, or claiming that nuclear power is more dangerous than has been shown to be true

Those denying hypotheses that mainstream science has found to be true, such as those denying that global warming is occurring

Additionally, people are using low quality scholarly journals to pursue personal theories or interests. These include:

Those claiming far-fetched cosmological discoveries or theories that are impossible to prove or disprove

Those publishing obvious pseudo-science, such as researchers documenting alien sightings

Those using predatory journals to support a business interest, such as those promoting a new, unapproved medicine

Those abusing the established taxonomy protocol to name species after themselves

The Future of Science

Science is cumulative, with new research building on findings already recorded in scholarly books and journals. When junk science is published bearing the imprimatur of science, later scientists may inadvertently use that work as the basis of their work, threatening the integrity of their results.

Google scholar does not sufficiently screen for quality and includes much junk science. To remain relevant and valuable. Google Scholar needs to limit the database to articles from authentic and respected scholarly publications and exclude articles from known publishers of junk science.