Can I use NOT to remove articles that are not relevant from my search?
Answer
You can do so, but it is not recommended unless you have advanced search skills as this can remove relevant articles from your search results. Expert searchers sometimes use what we call a “double NOT” to focus a comprehensive search on human studies, for example:
Lines 1- 23 [your search]
Line 24 Animals/
Line 25 Humans/
Line 26 1 NOT 2
Line 27 23 AND 26
NOT is better used to compare the results of two lines of your search so that you can examine what was found in one search line that was NOT found in the other, for example:
Line 1- penguin*.mp. = 2076 [articles found using the keyword]
Line 2- Spheniscidae/ = 1055 [articles found using the subject heading]
Line 3- 1 NOT 2 = 1080 [articles found using the keyword but not the subject heading]
Line 4 - 2 NOT 1 = 59 [articles found using the subject heading but not the keyword]
NB. this example also illustrates why it is important to searching using a combination of keywords and subject headings!