Google vs G Scholar vs PubMed vs Web of Science

Scope

Broadest

Biology, life sciences and environmental sciences, business, administration, finance and economics, chemistry and materials science, engineering, pharmacology, veterinary science, social sciences, arts and humanities

Specific: Bio-Medicine

Science, technology, social sciences, arts and humanities

Content scope

Searches billions of indexed web sites;

Includes all sorts of websites: government, organizations, commercial, individual sites, news

Indexes a wide range of scholarly (academic) literature including articles, dissertations, documents, reports, theses, court opinions, and abstracts, conference papers, court opinions, book chapters.

From: academic publishers, professional societies, online repositories, universities and other web sites

Indexes ~5400 peer-reviewed journals

Acceptable content is determined by an evaluation and selection process based on the following criteria: impact, influence, timeliness, peer review, and geographic representation

SCIE- Science Citation Index Expanded ~9200 journals

Selection

None

Content is selected by Google Scholar staff, who have been secretive about the sources included. Some publishers refuse to let Google Scholar search their web content.

Human curated: PubMed is controlled by human experts who systematically select data for inclusion in the database, and then describe and organize it.

Organized and maintained by experts

Human curated:

Source Languages

all

English abstract

English (plus 45 other languages

Search Engine

Searches:

every word seen on every webpage is indexed;
the search includes synonyms;

Plain language works fine

Advanced search

Controlled vocabulary

Filters and limits

Limited filters

Ability to focus with subject;

Sort by article type;

Different Filters

Different Filters

Ranking

Algorithm ranks relevance for you

Algorithm ranks relevance for you

Ability to sort results by date and relevance

Full text access

Free or open access

Can set up library access links

Can set up library access links

Quality

Hard to determine the credibility of sources- Must evaluate  each source for yourself

Easy to identify peer reviewed articles.

Need to learn how to use

Need to learn how to use

Citing articles

Shows number of citations

Citing articles from the indexed articles

How to search

Phrases with quotation marks.

Possible to combine terms with OR or (not).

Phrases with quotation marks.

Possible to combine terms with OR or (not).

Phrases with quotation marks.

Possible to combine terms with AND, OR, & NOT

Clinical Queries; Journal database

Display result

Possible to sort results by author, publication date, Including date, or journal.

Possible to show full abstract

Features

Register with 'My NCBI' to save searches, set up alerts & customize filters