Workshop developed to teach MLIS students how to effectively search for evidence-based medical information through Ovid-Medline and PubMed.

1. Accessing Medline- A
Workshop in PubMed and
Medline-OVID
Group members: Vivian, Bridget, Ashley,
and Kristen B

2. Today's Workshop
1. Learning Objectives (Kristen)
2. Medline (Kristen)
3. Literature Review (Ashley)
4. PubMed (Bridget)
5. PubMed-NCBI (Bridget)
6. Medline-OVID (Vivian)
7. Medline-OVID - My Workspace (Vivian)
8. Class Activity

3. Learning Objectives
1. Comparison of how MeSH maps natural
language differently between PubMed and
Medline- Ovid
2. Understand how to save, share, and
combine search strategies and auto-alerts
for PubMed and Medline-OVID
3. Understand how to export citations into
RefWorks from PubMed and Medline-OVID

4. Medline
• Premier, comprehensive biomedical
database in the United States
• Updated daily
• 5500 biomedicine and life science journals in
nearly 40 languages
• English abstracts are including for more than
80% of the records
• Full text coverage: 1948-Present
• Number of records: 18000000+

5. Literature Review
Allison JJ, Kiefe CI, Weissman NW, Carter J, Centor RM. The art and science of searching Medline to
answer clinical questions. Intl J of Technology Assessment in Health Care. 1999; 15 (2): 281-296.
Delwiche, FA. Searching Medline via Pubmed. Clinical Laboratory Science. 2008; 21 (1): 35-41.
De Groote, SL. PubMed, Internet Grateful Med, and Ovid: A comparison of three Medline internet
interfaces. Medical Reference Services Quarterly. 2000; 19 (4): 1-13.
Gault LV, Shultz MS, Davies KJ. Variations in medical subject headings (MeSH) mapping: From the
natural language of patron terms to the controlled vocabulary of mapped lists. J Med Libr Assoc.
2002; 90 (2): 173-180.
Katchamart W, Faulkner A, Feldman B, Tomlinson G, Bombardier C. PubMed had a higher sensitivity
than Ovid-Medline in the search for systematic reviews. J of Clinical Epidemiology. 2011; 64 (7):
805-807.

6. Lit Review Findings
• Usability and User Preference of Ovid vs. PubMed
• Effectiveness of search tool dependant on user’s familiarity with it
• Functionality (use of Boolean operators, truncations and proximity
searching)
• Variations in how Ovid and PubMed map free language onto MeSH
• Sensitivity of PubMed vs. Ovid in retrieving all relevant articles
• Use of Filters

7. User Preference
Thiele RH, Poiro NC, Scalzo DC, Nemergut EC. Speed, accuracy and confidence in Google, Ovid,
PubMed, and UpToDate: Results of a randomised trial. Postgrad Med J. 2010; 86: 459-465.
Google 45%
PubMed 25%
Ovid 4%
UptoDate 26%

8. Variations in MeSH Mapping
Gault LV, Shultz MS, Davies KJ. Variations in medical subject headings (MeSH) mapping: From the
natural language of patron terms to the controlled vocabulary of mapped lists. J Med Libr Assoc.
2002; 90 (2): 173-180.
Cannot assume symmetrical retrieval
from MeSH in different systems
Pubmed and Ovid provide methods
for suggesting mesh, but methods are
varying

9. SensitivityKatchamart W, Faulkner A, Feldman B, Tomlinson G, Bombardier C. PubMed had a higher
sensitivity than Ovid-Medline in the search for systematic reviews. J of Clinical Epidemiology. 2011;
64 (7): 805-807.
PubMed has higher sensitivity than Ovid
The Study:
• PubMed found more results for each concept
- rheumatoid arthritis, MTX and randomized
control trials
• 18 eligible articles were selected, Ovid had

10. Limits and FiltersWinchester DE, Bavry AA. Limitations of the MEDLINE database in constructing meta-analyses. Ann
Intern Med. 2010; 153: 347-8
• When search limits are used, researchers miss
important and relevant records
• Only limits that can be safely used are dates and
language – those not based on MeSH
• Applying search limits is not an integral part of search
strategy - well executed searches benefit from limits
when they are applied post hoc to remove unwanted
documents

11. Tips and Tricks Revealed
in Lit Review
1. Use both MeSH and free text words to limit Eg. search
"trial" as free-text in the abstract filed in addition to
MeSH
1. Use synonyms and truncation
1. Don't actively limit but use double negation Eg. (NOT
(Animals [MeSH] NOT Humans [MeSH])) - ensures no
non-indexed human studies are missed

12. PubMed - Introduction
• What is PubMed?
• Types of Citations
• Advanced Search Builder
• Automatic Term Mapping
• MeSH Subheadings (Qualifiers)
• Search Field Descriptions & Tags
• Filters
• Features (Single Citation Matcher, Clinical Queries & My
NCBI)

13. PubMed - What Is It?
• Free access to MEDLINE
• Links to full-text articles in PubMed Central,
publisher web sites, and other related
resources
• Over 22 million citations
• Developed & maintained by the National
Center for Biotechnology Information (NCBI)
at the U.S. National Library of Medicine

14. PubMed - Type of Citations
• PubMed - as supplied by publisher
• PubMed - in process
• PudMed - indexed for MEDLINE
• PubMed
• PubMed - OLDMEDLINE

15. PubMed - Example:

16. May miss non-indexed papers or "wrongly
indexed" papers if only MeSH is used
Use both MeSH terms AND keywords, including synonyms, related terms, variant endings and
spellings
PubMed - Comprehensive
Searching

17. PubMed - Advanced Search
Builder
•
• Choose a field (if you like)
• Run Search
• Combine search strings
Isolate concepts

18. PubMed - Automatic Term
Mapping (ATM)
• Maps keywords to MeSH headings, journal
titles or author names
• Splits phrases apart and searches each term
separately and combines them
• Parts of a search can be removed and/or
added and rerun

19. PubMed - Keep in Mind...
•
• PubMed ignores Stopwords (i.e. because,
regarding, mostly, however, each, etc.)
List of Stopwords:
http://www.ncbi.nlm.nih.gov/books/NBK3827/ta
ble/pubmedhelp.T43/?report=objectonly

20. PubMed - Use with
Caution...
•
• Phrase searching is possible with "double
quotations"
*Warning: Using truncation or quotations will
automatically turn off mapping and MeSH term
explosion (try to use in addition by combining
with OR)

21. Use the MeSH database to find a suitable term and "Add to Search Builder", then run your search in
PubMed
PubMed - Wrong Term
Mapped?

22. PubMed - MeSH Search
Tags (Qualifiers)
[mh] To search a MeSH heading
[majr] To search a MeSH heading that is a
major topic of an article

23. PubMed - Warning:
Warning: Using only MeSH subject terms excludes in-process & publisher-supplied citations & others
that do not (or do not yet) include MeSH subject terms

24. PubMed - MeSH Search
Tags No Exploding
Turn-off automatic explosion by adding :noexp
i.e. [mh: noexp]
[majr: noexp]
Terms will automatically explode

25. PubMed -
MeSH Subheadings
Want to Get More Specific?Add MeSH
Subheadings (also called Qualifiers) by adding a slash
and typing in the Qualifier's name or the Qualifier's
abbreviation
i.e.
eye/injuries [majr]
or
eye/in [majr]
*case and spacing don't matter
*cannot turn off the explode feature for a subheading

26. PubMed - Subheadings
cont'd
List of Subheadings:
http://www.ncbi.nlm.nih.gov/books/NBK3827/table/
pubmedhelp.T41/
Subheading Definitions:
http://www.nlm.nih.gov/mesh/topsubscope.html
Qualifier Hierarchies:
http://www.nlm.nih.gov/mesh/subhierarchy.html

27. PubMed - Search Field
Descriptions/Tags
List of PubMed Data Element Field Descriptions:
http://www.ncbi.nlm.nih.gov/books/NBK3827/tabl
e/pubmedhelp.T44/?report=objectonly
Limits your search

28. PubMed - Author Field
•
i.e. austin j [au]
• Will automatically truncate. To stop this, add
quotations
i.e. "austin je" [au]

29. PubMed - Date Field
•
• To search for a specific date, use this format:
YYYY/MM/DD [date field]
*month and year are optional

30. PubMed - Date Field
cont'd...
Date Field
Date ranges can be entered with a colon
i.e., 2004:2006
Comprehensive searches for a full year
i.e., 2000:2000
(will retrieve citations with a different print and
electronic year of publication)
Searching by date FAQ:

31. PubMed - Filters
•
• Select filter (left side of screen)
• Click on "Show Additional Filters" if
necessary
*Filters will remain for all subsequent searches
unless they are cleared

32. PubMed - Single Citation
Matcher
•
• Enter the information you have to fill in the
blanks
• Click go

33. PubMed - Clinical Queries
A search interface to find citations in the areas of:
• Clinical Study Categories: Find citations corresponding to a
specific clinical study category.
• Systematic Reviews: Find citations for systematic reviews,
meta-analyses, reviews of clinical trials, evidence-based
medicine, consensus development conferences, and
guidelines.
• Medical Genetics: Find citations related to various topics in
medical genetics.

34. PubMed - My NCBI
•
• Need to register (free!)

35. PubMed - My NCBI:
User Preferences
Some include:
• Link options
• Email options
• Display highlighted terms
• Single Citation Display

36. PubMed - My NCBI:
Filtering Options
•
• Can customize your own filter and name it

37. PubMed - My NCBI:Save
Search Strategy & Alert Setup
• Max number of saved searches is 100 per
user-name
• Saved searches cannot be edited
• Limited to one email address per account
*related articles cannot be saved; date and date ranges are

38. PubMed - RefWorks
Refresher
In PubMed...
1) Mark appropriate records in your search
2) Add to Clipboard (from "Send to" menu)
3) Display the Clipboard contents
4) Change "Display Settings" to Medline format
5) Select and Copy all of the text

39. PubMed - RefWorks
Refresher Cont'd
In RefWorks....
6) Select References > Import
7) Select NLM PubMed from the Import Filter drop
down menu
8) PubMed will appear automatically as the
database
9) Click on the From Text link
10) Paste text into the box
11) Click IMPORT

40. Medline-OVID
• Uses OvidSP - their flagship research platform
• More than 2500 ebooks and collections, including archive
collections of critical historical materials, as well as publisher
and topical collections
• Over 1300 premium, peer-reviews journals, including dozens
of journal collections
• Over 100 bibliographic and full-text databases
• Disciplines: Medicine, Nursing & Health Professions,
Behavioural Sciences, Basic Science, Humanities &
Technology

41. Medline-OVID
Mapping
• OVID uses vocabulary mapping which searches using natural
language terminology
• The mapping process uses OVID's statistical algorithm to
determine which terms are associated with certain subject
headings
• The use of mapping increases a user's retrieval precision
• Ovid will automatically maps search terms to the database's
controlled vocabulary

42. Medline-OVID
Command Line Syntax
• Allows shortcut commands to be added to a user's search,
circumventing the use of the icon bar
• Use of command line in OVID overrides MeSH mapping
Examples:
• exp <term> - This command within a controlled vocabulary
database would explode the term
• * <term> - This command within a controlled vocabulary
database would focus on that term
• <term>.ab. - This command would search term term through
the abstract (ab) field of the database

43. Medline-OVID
Truncation and Wild Cards
• Unlimited truncation - "$" or ":", such as "cancer$" which will
retrieve "cancer", along with "cancers" and "cancerous"
• Limited truncation - "$" or ":" paired with a number will retrieve
the root word with that maximum number of character, i.e.
"dog$1" will retrieve "dog" and "dogs", but not "dogma"
• Mandated Wild Card - "#" is used within or at the end of a term
to substitute one required character, i.e. "wom#n" will retrieve
"women" and "woman", however "dog#" will retrieve "dogs", but
not "dog" because it require another character to be present
• Optional Wild Card - "?", used to substitute one or no
characters, useful when dealing with American/British word
variants, i.e. "colo?r" will retrieve "color" and "colour", however
"?" will not work if there is only one letter before the wild card

44. Medline-OVID
Stopwords
• Words with that hold little value or meaning
• These words are often discarded in a search unless
• Ovid has elimated Stopwords, now user's can search
words/phrases such as "is there hope.tw"

45. Medline-OVID
RefWorks
• Bibliographic information can be exported into RefWorks in
Ovid

46. Medline-OVID - My
Workspace
My Searches & Alerts
•Search strategies/strings can be saved
o
Save as Temporary (24hours)
o
Save as Permanent (valid subscription)
o
AutoAlert (searches automatically on regular basis and
emails the results)
o
Expert Searches (An expert creates a search strategy
that is shared and available to allow multiple users to
share searches on the same group account)
My eTocs
•Email alerts user when the journal they subscribe to updates its

47. Class Activity
Follow instructions on your handout and
complete exercises.
If you have any questions, raise your hand and
we can help.
Class discussion

48. MeSH Variations
Ovid: Depression (default) but there are other
choices in list
PubMed Automatic Mapping: Depressive
disorder OR depression
PubMed Mesh Browser: Depression,
depressive disorder and more options

49. PubMed Mesh Browser or
Default Search?
• PubMed Browser is more like Ovid - building
block style with user control over which
MeSH is selected
• PubMed default automatic mapping is
intelligent and handy, but it doesn't always
account for all MeSH that could be used but
can retrieve more documents...
Choosing how you want to search is up to you!

50. Differences in Ovid's MeSH list and
PubMed's Browser List
Ovid provides shortest list of MeSH choices
(average is 8 terms) with a selection rate of
62%
PubMed has a list 3x longer with a selection
rate of 63% (Gault et. al)
Not much difference...

51. Combining Concepts and
Results
PubMed MeSH Browser:
((("Depression"[Mesh]) OR "Depressive Disorder"[Mesh]) AND "Mass
Screening"[Mesh]) AND "Women"[Mesh]
# of results - 17
PubMed Automatic Mapping:
("depressive disorder"[MeSH Terms] OR ("depressive"[All Fields] AND
"disorder"[All Fields]) OR "depressive disorder"[All Fields] OR
"depression"[All Fields] OR "depression"[MeSH Terms]) AND ("mass
screening"[MeSH Terms] OR ("mass"[All Fields] AND "screening"[All
Fields]) OR "mass screening"[All Fields]) AND ("women"[MeSH Terms]
OR "women"[All Fields])

52. Combining Concepts and
Results
Ovid (user selection):
Depression and mass screening and women
# of results - 6

53. Command Line
Answer for PubMed Field Descriptor
Question:
hepatitis b[mh] AND Murphy TV[au] AND 2012:2013[pd]
Answer for Ovid Dot Commands:
hepatitis b. and Murphy TV.au and 2012:2013.yr
OR
hepatitis b. AND Murphy TV.au AND 2012:2013.yr