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Table of Contents• Review of Prior Lessons: Evide
nce Pyramid• Using the Cochrane Library
– Purpose of the Cochrane Library– Access the Cochrane Library thro
ugh the ATSU Portal– Search the Cochrane Library
•Advanced Search•MeSH Search•Search History•Saved Searches
Brief Review:Evidence Pyramid
• The best evidence is located at the top of the pyramid.
Which of the following does NOT describe all systematic reviews?• comprehensively synthesizes informati
on from several other articles
• uses a selection criteria in the inclusion/ exclusion of articles
• critically appraises material from various other articles
• uses statistical methods to combine all of the data from different articles
The Purpose of the Cochrane Library
• Collection of databases of articles which serve as a basis for your clinical treatment decisions with Cochrane Reviews containing systematic reviews.
Try it Yourself: Access the Cochrane
Library (Video)• View movie as:
– QuickTime (.mov)
– Flash (.swf)
• Double-click on video for full-screen mode.
Try it Yourself: Access the Cochrane
Library (Text)• Type http://my.atsu.edu in the address bar of your internet search engine (Internet Explorer, etc.).
• Enter your username and password.
• Click Library on the left.• Then click KCOM Library.• Click Online Medical Resources.• Finally click Cochrane Library
•Advanced Search•MeSH Search•Search History•Saved Searches
Cochrane Search Tools:
Search Boxes
• Drop-down boxes include primary operators and fields. Use these to construct your search.– Do not forget about the order of
operation as discussed in the lesson on PubMed (and further discussed later).
Restrict by Study Type
• Check-boxes allow one to specify what types of studies to look for.– If All of The Cochrane Library is
checked or multiple checkboxes are checked, the categories are separated and are accessible by tabs across the top.
Record Status and Date Range
• Can restrict by various statuses• And within a range of dates
Search Results• At first it may appear only to
have found a few articles,
but the Cochrane
Library is a compilation of
databases. It only shows
articles from one at a time.
Use the tabs above to view
others.
• Your patient is a 32-year-old male construction worker with acute low back pain, who wants to prevent it from worsening. He refuses spinal manipulative therapy and alternative medicine treatments.
Try it Yourself: Scenario
• Form a relevant question according to the procedures in Step 1 with respect to the patient and his preferences.
• Now it’s time to do a literature search.
• Use Advanced Search to seek the best available evidence to improve his current condition and prevent its recurrence.
Try it Yourself: Steps 1 & 2
• Now step out of your comfort zone for a moment. Use some of the search features you typically ignore.
• Try typing in wildcards (*) to increase results and phrases surrounded by quotation marks (“”) to decrease results.– Note: These are used in the
Cochrane Library searches just as they were in PubMed.
Try it Yourself: Step 2
• How drastically did each of these affect your search results?
• What helpful features do each of these offer?
• How could you use these more effectively?
Try it Yourself: Thinking about Step
2
• These are the terms from the U.S. National Library of Medicine’s controlled vocabulary
• Advantages:– Provide a way of finding articles
treating the same topics while using different synonymous words
– Arranged hierarchically, allowing one to choose broader or more precise terminology as needed
MeSH/Medical Subject Headings:
• Go to MeSH Trees– Locates hierarchies of MeSH terms that
contain that word.• (If that word is not a MeSH term, the
thesaurus is searched.)
• Thesaurus– Retrieve all MeSH descriptors
containing that word– Finds MeSH terms corresponding to
that word
• Definition– Defines MeSH terms
Exploring MeSH/Medical Subject
Headings:
• View syntax used for previous Advanced Searches.
• Take more control over your searches using the Search for box at the top.
• Include operators that do not have drop-down boxes.
Search History:
• AND – Conjunction/Include both words
• OR – Disjunction/Include one word or the
other (possibly both)
• NOT – Exclusion/Do not include the word
• Do not need to be capitalized, but still a good habit– Unlike PubMed
Cochrane Search Operators:
• * (Asterix)– Wildcard/Truncation/Replaces a string of
letters• hyp*thermia retrieves both hypothermia and
hyperthermia.
• ? (Question mark) – Wildcard/Replaces a single letter
• analys?s retrieves both analysis and analyses.
• () (Parentheses)– Controls order in which operations are
applied
• # (Pound Sign) (followed by number)– Recalls a numbered search from your
search history
More Search Operators:
• “” (Quotation Marks)– Phrase/Include if the exact phrase is
included (No variants)
• NEAR/ (followed by a number)– Proximity/Include if words are {number}
words apart
• NEXT – Proximity/Include if word stems follow
each other, separated by a space or a dash
– May be more useful than “” (quotation marks) when you still need to include plurals or other operators• Example: colorectal NEXT *noma* retrieves
entries on colorectal adenomas and colorectal carcinoma
Even More Search Operators:
• You can also search by abstract (:ab), author (:au), keywords (:kw), source (:so), title (:ti), publication type (:pt), tables (:tb), or DOI (:doi).
• Combine these by placing commas between each field. (Only one : (colon) is needed.)
• Example:– "hepatocellular carcinoma":ti,ab,kw
Cochrane Fields:
• Spacing defaults to AND• Stemming accounts for the many
common spelling variants and most plurals– For example tumour retrieves tumour,
tumor, tumours, and tumors.– Can use * (asterix) to be sure to retrieve
these alternatives
• Not sensitive to capitalization• Accented character not matched to
unaccented forms
Cochrane Searches:
• Did you retrieve unexpected results from your search?– Try using parentheses around your search
terms.– Then see if you understand the order in
which certain operations are applied.
• Helpful with site-specific operations• Think of some simple searches that
may help us determine this. Try them out.
Ways to DetermineOrder of Operations:
• Example: word 1 AND word2 OR word3
could be interpreted in 2 ways:– ((word1 AND word2) OR word3)– (word1 AND (word2 OR word3))
• This makes a big difference when word1 does not retrieve any articles and word3 retrieves many.– The 1st would show many while the
2nd would show none.
Determining Order of Operations:
• Try this out by typing gibberish for word1, any word for word2, and a common term for word3.– Which interpretation did the search
engine use? Which operation gets applied first? AND or OR?
Try it Yourself:Determining Order of
Operations
• Now using Search History, access your previous searches.
• Copy and paste some of the syntax into the Search for box above. Then alter these queries to try out the search operators you just learned about.
• What effects did these have?• How can these help you become
more efficient?
Try it Yourself:Using Search History
• You can save searches and sequences of searches and rerun them at a later time. – While Search History is cleared
between sessions, Saved Searches remain.
– You can rerun these as needed or use a series of searches as a template, which you can edit for more specific searches.
Saved Searches
Links to Other Websitesand Hands-On Activities
• The Cochrane Library User Guide• From Suny Downstate Medical
Center– Applying EBM to Online Searches
