How to know if a journal is indexed in PubMed or Google Scholar? What's the difference?
What does indexing a journal means?
- It means the journal's bibliographic information, abstracts, and sometimes full texts have been added to the database, and by searching the databases, you will be able to find them.
- It also means some level of light quality check has happened for a journal to meet the criteria for being indexed in the database.
- Indexing on some databases also means human/machine/both have extracted/assigned or will extract/assign controlled vocabulary to each article to improve their retrieval/findability.
Why is it important for a journal to be indexed or for researchers to publish in these journals?
One word, visibility. The main and probably the only benefit of indexing journal or publishing in indexed journals is making your work visible. So if you can make your work publicly available and visible (indexed), you won’t need journals at all.
Of course, peer review is another process that is part of publishing in journals, but you don't need to publish in journals to have peers review your work! Some of the greatest academic works (including dissertations are peer-reviewed outside the commercial publishing ecosystem.
How does Google Scholar index the journal articles?
Google Scholar's indexing takes place automatically based on the meta-tags or meta-data from the webpage of each article or metadata in files (PDF, DOC, DOCX, PPT, etc.). It also indexed the main free and public sources of articles such as PubMed, preprint databases, etc. For full details on its indexing guides, please see here: https://scholar.google.co.uk/intl/en/scholar/inclusion.html
About 15 years ago, I followed these guidelines to index about 23 journals in Google Scholar.
As I mentioned “search engines such as Google Scholar do not provide the list of journals they index” mainly because such a list would require human curation and is costly and also because of web and search engine dynamics.