Planning a
Search Strategy
PICO, Concept Boxes and
Boolean Operators
Online Searching
at a Glance
• Useful terminology:
o Pearl Searching: find a good article aka pearl
and look at the references
o Boolean operators: most databases allow
boolean operators to narrow or broaden a
search (AND, OR, NOT)
o Truncation: most databases use symbols such as *
for truncation, e.g., dent* will retrieve dental,
dentistry, dentist, etc.
BOOLEAN
SEARCHING
Using AND, OR, and NOT
AND
bisphosphonates AND
osteonecrosis
OR
osteonecrosis OR death of bone
OR bone death OR bone
necrosis
NOT
osteonecrosis NOT femur
head necrosis
Truncation
Using * (asterisk) and
? (question mark)
Using * to truncate retrieves any ending
after the truncated part of the word.
• Manag* will retrieve manage,
management, manager, etc.
But, be careful
Truncating too soon can be
problematic
cat* catapult
cat
cattle
cats
http://www.vetprofessionals.com/catprofessional/
http://ochumanesociety.com/dogs---cats-for-adoption/available-pets/cats-and-kittens.htm
http://www.swordsandarmor.com/mall/miniature-Catapult-Siege-Weapon.html
http://www.wisegeek.com/what-is-a-cow.htm#slideshow
? will find different spellings
within a word
wom?n will retrieve woman
and women
? can also be used to find
British/Canadian and American
spelling
gr?y cat
gr?y cat
grey cat
gray cat
http://blog.sureflap.com/tag/animal-shelters/
http://dnakluski.files.wordpress.com/2010/10/canadian-flag.gif
http://goodamericanpost.files.wordpress.com/2010/05/american-flag1.jpg
British and North American spellings vary. When entering textwords in search engines for international databases
such as Cochrane or Medline, it is necessary to allow for the different spellings, or else some citations may be missed.
Use $ or : to get all possible endings (e.g. comput:.mp. for computer, computers, computing, computed, etc.)
Use # to replace exactly one character (wom#n.mp. for woman or women)
Use ? to replace 0 or 1 character (labo?r.mp. for labor or labour)
Examples
U.S.
British
anemia/anaemia
etiology/aetiology
gynecology/gynaecology
hemoglobin/haemoglobin
esophagus/oesophagus
fetus/foetus
diarrhea/diarrhoea
-e-
-ae-
In OVID, enter as:
an?emia
"etiology or aetiology"
gyn?ecology
"hemoglobin or haemoglobin"
"esophagus or oesophagus"
"fetus or foetus"
diarrh?ea
-e-
-oe-
tumor/tumour
-o-
-ou-
tumo?r
organize/organise
-z-
-s-
organi#e
counseling/counselling
counseled/counselled
-l-
-ll-
counse$ling for specific ending
counsel
sulfur/sulphur
-f-
-ph-
sul#?ur
fiber/fibre
-er-
-re-
fib:
Steps to finding articles
• Identify the main concepts or keywords
• Determine the best resources
• Plan the search
• Document the search and cite
• Evaluate what you find
Example topic
Your hospital wants to implement a policy of placing
all HIV+ patients on INH prophylaxis therapy. You
have been asked to do a review to see if that is
successful in preventing tuberculosis, in particular in
other African countries.
Identify the main
concepts
• The easiest way to make your question searchable
is to break it up into concepts
• For each concept, think of as many
keywords/synonyms as you can
• A very popular method to use is PICO
Identify the main
concepts
• PICO Method
P
I
C
O
– Population
– Intervention
– Comparison (Optional)
– Outcome
PICO Example Continued
P – HIV positive in African countries
• I – INH prophylaxis therapy
• C – n/a
• O – decreased rates of tuberculosis
•
Answerable Question: In African countries does INH
prophylaxis therapy help reduce the rates of
tuberculosis among HIV positive patients?
Think of synonyms or similar terms
or ideas to use in your search
PICO
PICO concepts
Possible search terms
Patient Population
HIV positive patients in
African countries
HIV positive, HIV infection,
human immunodeficiency
virus, Africa, Ethiopia,
Eastern Africa
Intervention
INH prophylaxis therapy
INH prophylaxis therapy,
INH preventive therapy,
Isoniazid, IPT
Comparison (if any)
n/a
n/a
Outcome
Reduction of cases of
tuberculosis
Tuberculosis
Determine the best
resources
 There are hundreds of article databases available.
Which one will you use?
 Most popular databases are:
1.
2.
3.
4.
5.
6.
MEDLINE (accessible either through PubMed or Ovid)
Cochrane Library
EMBASE
Web of Science
Scopus
Google Scholar????
Plan the search
• Now you have your searchable questions and
keywords. Where do you start?
• Each database has its own indexing system. Many
have their own thesaurus or list of subject headings.
If the database you are using has a thesaurus,
match your keywords to the thesaurus for a more
efficient search.
Using a database
Once you’ve chosen a database, such as Medline or
PubMed, search for each concept separately
Use OR to combine synonyms or similar terms or
concepts (HIV+ OR HIV positive)
Use AND to combine separate concepts (HIV positive
AND tuberculosis AND INH prophylaxis therapy)
Document the search and
cite
• Save your searches by creating an account in each
database that you use
• Use a citation management tool such as Zotero,
Medeley or Endnote Web to export your citations
from multiple databases
Evaluate what you find
• Please always evaluate the information you find,
either by using given criteria or developing your
own