Using truncation
and Boolean
operators
6 steps to an effective
literature search
Step 4: Compile your
search strategy & run your
search
Beginner
This guide gives brief information on how to put your search together. There is more
help on the Library webpages at
http://www.lshtm.ac.uk/library/guidance/lit_search/index.html.
Note: Not all of the resources allow you to use all of these functions. Please check the
‘About this database’ link on the Library databases pages or the help pages supplied
with the resource itself.
Truncation
Truncation can be used in practically all search systems (except Google – the search
engine will automatically apply truncation for you). Just add an asterisk (*) to the root of
the word you want to search for and the system will automatically look for words which
start with the letters you have entered, regardless of which characters come after it.
Example:
Entering organisat* will find the following words:
organisation, organisations, organisational, organisationally
Do not make the root of the word too short. Entering organis* will find the following
additional words:
organism, organisms, organise, organised, organiser, organist.
Using Boolean operators
OR
cost
budget
Library & Archives Service
www.lshtm.ac.uk/library/
library@lshtm.ac.uk
@LSHTMLibrary
+44 (0)20 7927 2276
Use OR when you are entering
your synonyms. OR will find
articles with one or more of your
terms, the light and dark sections
of the Venn diagram.
AND
open angle
glaucoma
screening
cost
Use AND when you are combining
different topics together. AND will
find articles with all of your terms,
only the dark section in the centre
of the Venn diagram.
Combining your searches together
When you are using AND and OR in a search, you must use brackets ( ) to ensure the
resource understands the logic of your search strategy and runs each part of your
search in the correct order.
Combine each of your synonyms for concept 1 with an OR, then put brackets around
them. Do the same with each of your other concepts, then use AND to link your
concepts together.
You would structure your search something like shown below:
(concept 1 synonym OR concept 1 synonym OR concept 1 synonym) AND (concept 2
synonym OR concept 2 synonym OR concept 2 synonym) AND (concept 3 synonym
OR concept 3 synonym OR concept 3 synonym)
So, a search on the cost-effectiveness of open-angle glaucoma screening would look
like:
(open-angle glaucoma OR simple* glaucoma* OR compensa* glaucoma* OR
pigmentary glaucoma*) AND screening AND (cost analysis OR cost benefit OR cost
effective* OR economic*)
How do I get more help?
The Library has produced a series of handouts and videos on the 6 steps to an
effective literature search. These are on our website at
http://www.lshtm.ac.uk/library/guidance/lit_search/index.html.
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24 September 2014