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2.4.c Boolean operators


Are you familiar with the Boolean logic?

PubMed uses some special search rules and syntax.
The Boolean operators (connectors) are words as AND, OR, and NOT.
AND, OR and NOT must be entered always in UPPERCASE.

AND is the default operator used in PubMed!
If you do not include Boolean operators in your search, PubMed will automatically use AND between terms.
PubMed processes Boolean connectors in a left-to-right sequence.

Looking at the previous example:

Should HIV-positive pregnant patients take ART to prevent mother-to-child transmission (PMTCT) of HIV?

P= HIV-positive pregnant woman
C= (no treatment)
O= decrease of the risk of mother to child transmission

From this PICO, a good search strategy using Boolean might look like:

HIV PMTCT (Highly Active Antiretroviral Therapy OR HAART OR triple therapy)