We’ve all heard of Boolean logic at some point in our careers whether it be during a consultation with an MSK Informationist (or other librarian), or in a more formal training setting during a survey college course. Whether we use the AND, OR, and NOT operators during simple and complex database searching is a different story. Take a look at the following examples for tips on effectively using Boolean operators.

AND = Conjunction (use AND to combine keywords/phrases in a search to view results where both/all of the AND’d terms appear).

• Example: looking for papers on patients with glioblastoma who are treated with both chemotherapy and radiation.
• You can set up this search as follows, pulling out the major components and AND’ing them together:
  glioblastoma AND chemotherapy AND radiation

OR = Disjunction (use OR to retrieve results where either of your search terms appear)

• Example: need to find research where temozolomide or radiation treatment options took place in patients with glioblastoma.
• You can set up the search as follows, pulling out the major treatment components and OR’ing them together, while AND’ing the disease/condition:
  temozolomide OR radiation AND glioblastoma

NOT = Negation (use NOT to exclude certain keywords/phrases from an overall search results set)

• Example: looking for articles with any chemotherapy treatment options discussed for glioblastoma except for temozolomide.
• You can set up the search as follows, pulling out the major components and AND’ing them together, while NOT’ing the undesired chemotherapy treatment option:
  glioblastoma AND chemotherapy NOT temozolomide

Many of the major databases have built-in Boolean operators in the “Advanced” search options of their interfaces. Ask us for more details or to set up a research consult on a database of your choosing. We can even provide a general overview on formulating effective search strategies in any database.