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Basic Searches & PubMed
Table of Contents• Using the ATSU link-out to PubMe
d (requires access to the ATSU Portal)
• Brief lesson on general use of PubMed
• Try it Yourself: Using PubMed to find a systematic review
ATSU link-out to PubMed • From within
the Portal, access the Library >>
KCOM Library tab (in the left frame).
• From the Online Medical Resources page, click PubMed Tabbed Linkout - ATSU Kirksville.
• View movie as• QuickTime (.mov
)• Flash (.swf)
Using PubMed in General• View movie as:
– QuickTime (.mov)
– Flash (.swf)
• Double-click on video for full-screen mode.
• Try using Boolean operators† like:– AND (include both words)– OR (include one word or the other)– NOT (do not include the word)
• Must be capitalized• If you want search for a phrase or
force one word to follow another, use quotation marks: “”
Useful Search Tools:
† Not PubMed-specific. Can be used with most search engines.
• Searches for items containing both what precedes it and what follows it.
• Narrows search• Example: dyspnea AND “cardiac
failure”– (Actually this example does not
produce better results than a search for dyspnea “cardiac failure” because PubMed automatically uses an AND operation between words in the absence of other Boolean operators. So the two are the same.)
AND
• Searches for items containing either what precedes it or what follows it (but it could include both).
• Broadens search• Often used with synonyms and
related terms• Example: chickenpox OR varicella
OR
• Searches for items that do not contain what follows it.
• Narrows search• Never precede it with AND.
– When 2 operators follow each other, only the first is applied.
– So metathesis AND NOT “double decomposition” is equivalent to metathesis AND “double decomposition” .
• Problematic when trying to exclude chemistry articles.
NOT
• ()– Control the order of
operations– Without parentheses:
•AND’s applied before OR’s and NOT’s
•Applied left to right
Parentheses
• chemotherapy AND "eye cancer" OR retinoblastoma– retrieves entries containing the
keyword “retinoblastoma” without the word “chemotherapy.” Any retrieved entries with “chemotherapy” also contain “eye cancer.”
• In contrast:• chemotherapy AND ("eye cancer" OR
retinoblastoma)– retrieves entries with the keyword
“chemotherapy” that additionally contain either "eye cancer" or “retinoblastoma.”
Useful Search Tips:
• *• Retrieve all words with a common
string of letters. Wild cards (*) replace any combination of letters or lack thereof.
• Broadens search• Commonly used for related word
roots. – So pyelotom* will retrieve pyelotomy
and pyelotomies, as well as pyelotomia, pyelotomized, and pyelotomography. Using NOT can eliminate these common but unwanted terms.
Wild Card *
• You have a 72-year-old female patient with dyspnea. You need to employ the best available evidence to accurately determine if cardiac failure is the cause or not.
• Form a relevant question according to the procedures in Step 1.
• Now it’s time to do a literature search.
Try it Yourself:
• Log into PubMed.• Click on Clinical Queries on the left
(below the PubMed Services heading).
• First try to find systematic reviews since these combine and filter the information from multiple studies, giving a more comprehensive view than any single study.
• Write your search down.
Try it Yourself: Using Clinical
Queries
• Did you find anything useful?• Did you use Boolean operators
and wild cards?• How many relevant articles did
you find?• What other information would you
like to have before making a clinical decision?
Try it Yourself: Assess Your Search
• Search too narrow?– Try using wild cards. Try dyspn*
instead of dyspnea. This will retrieve dyspneic, dyspneics, and other related terms.
– Try including synonyms, separated by OR’s. How about “cardiac failure” OR “heart failure”?
Try it Yourself: Fixing a Narrow
Search
• Search too broad?– Try including more relevant terms or
clusters of relevant terms, surrounded by parentheses and separated by OR’s
– Use NOT’s to eliminate unwanted material (taking caution not to overlook useful ones).
Try it Yourself: Fixing a Broad
Search
• Try this out:• (dyspn* OR "shortness of breath")
AND (cardi* failure OR "heart failure") †
• Did it provide relevant resources? Why or why not? What can you do to improve this example?
Try it Yourself: An Example
† Requires AND systematic[sb] if not typed in the Systematic Reviews box.
• Try out some new searches. Be creative. Also, click on the Details tab near the top to see the expanded search.
• Could any of these be helpful for diagnosis?
Try it Yourself: Expanding Your
Abilities
† Requires AND systematic[sb] if not typed in the Systematic Reviews box.
• PubMed uses a controlled vocabulary (MeSH)
• This allows you to search by different topics.
• Learn more about this using the tutorials.
MeSH
† Requires AND systematic[sb] if not typed in the Systematic Reviews box.
• Try to find articles using this feature.
• You can also type these into the Systematic Review bar followed by [MeSH], like in the following example:– Heart Failure, Congestive[MeSH] AND
Dyspnea[MeSH] †
Try it Yourself: MeSH
† Requires AND systematic[sb] if not typed in the Systematic Reviews box.
• You can also combine these MeSH terms with those from your previous searches, as seen below:– (dyspn* OR "shortness of breath“ OR
Dyspnea[MeSH]) AND (cardi* failure OR "heart failure“ OR Heart Failure, Congestive[MeSH]) †
• After you are comfortable with the earlier material in this lesson, try these out. What advantages do MeSH terms provide?
Try it Yourself: Using MeSH
† Requires AND systematic[sb] if not typed in the Systematic Reviews box.
Links to Other Websitesand Hands-On Activities
• From the A.T. Still University Arizona School of Health Sciences– Guide to PubMed
• From Suny Downstate Medical Center– Applying EBM to Online Searches
