embase.com webinar presented on 25th february 2015, on systematic searching for medical librarians. How to search systematically for instance for a systematic review. How can you check for completeness of the terms used. The original presentation contained a live demonstration, but here screenshots are shown within the presentation. A recording of the webinar can be found at: https://attendee.gotowebinar.com/recording/293088383310057474

1. A unique method for fast, high-
quality systematic searching
Wichor M. Bramer
Erasmus MC
Rotterdam the Netherlands
Embase.com webinar – 25 february 2015

2. Research Question
Is exercise therapy an effective
treatment for hip osteoarthritis
Simple search strategy:
exercise therapy effectiveness hip osteoarthritis
155 hits

3. ('hip osteoarthritis'/exp OR ((arthritis/de OR
osteoarthritis/de) AND (hip/de OR 'hip pain'/exp)) OR
(coxarth* OR ((hip OR cox) NEAR/6 (arthrit* OR
arthrosis* OR arthroses* OR osteoarth* OR oa)) OR
'malum coxae senilis'):ab,ti) AND ('kinesiotherapy'/exp
OR exercise/exp OR physiotherapy/exp OR 'conservative
treatment'/de OR (kinesiotherap* OR kinesitherap* OR
exercis* OR physiotherap* OR gymnastic* OR
((movement* OR motion OR manual OR phys* OR
conservative* OR nonoperat* OR nonsurg* OR non-
operative OR non-surgical OR paramedic* OR para-
medical) NEAR/3 (technique* OR therap* OR treat* OR
isokinet* OR isomet* OR water OR management* )) OR
((muscle* OR muscul*) NEAR/3 (train*))):ab,ti)
Systematic search strategy
1916 hits

4. Systematic searching
≠
Doing a systematic review
Systematic reviews need systematic searche(r)s but:
The systematic approach can be used for more than
just searching systematic reviews
Performing systematic reviews is more than just
searching systematically

5. Creating an optimal syntax in embase.com
(Agenda for this webinar)
1. Identify most relevant emtree terms and free
text words
2. Create a syntax combining those terms
3. Optimize the syntax to identify missing terms

6. Step 1: identifying emtree terms
One element  One emtree term

8. Step 1: identifying emtree terms
One element  One emtree term
'familial hypertrophic cardiomyopathy'
One element  More emtree terms

13. Step 1: identifying emtree terms
One element  One emtree term
'familial hypertrophic cardiomyopathy'
One element  Multiple emtree terms
prevention OR prevention:lnk OR 'prevention
study' OR 'preventive health service' OR …
Multiple elements  One emtree term

19. Step 1: identifying emtree terms
One element  One emtree term
'familial hypertrophic cardiomyopathy‘
One element  Multiple emtree terms
prevention OR prevention:lnk OR 'prevention
study' OR 'preventive health service' OR …
Multiple elements  One emtree term
('cancer mortality' OR (neoplasm AND mortality))
(neoplasm OR 'cancer mortality') AND (mortality
OR 'cancer mortality')

20. Step 1: identifying free text words
Optimal sensitivity only by additionally searching
in title / abstract:
• Relevant, non-inverted terms from synonyms

22. Step 1: identifying free text words
Optimal sensitivity only by additionally searching in
title / abstract:
• Relevant, non-inverted terms from synonyms
(neoplasm) tumo* OR cancer* OR neoplas*
• Relevant words / phrases from narrower terms

24. Step 1: identifying free text words
Optimal sensitivity only by additionally searching in
title / abstract:
• Relevant, non-inverted terms from synonyms
(neoplasm) tumo* OR cancer* OR neoplas*
• Relevant words / phrases from narrower terms
(large intestine tumor)
'anus tumor' OR 'appendix tumor' OR 'cecum tumor'
OR 'colon tumor' OR 'rectum tumor'
• The emtree term itself
Next: step 2  Create a syntax

25. Embase.com OvidSP PubMed
Boolean AND, OR, NOT
Thesaurus /exp exp …/ [mh]
---- Unexploded /de …/ [mh:noexp]
Title / abstract ():ab,ti ().ab,ti. [tiab]
Phrases ‘single quotes’ No quotes
needed
“Double quotes”
or *
Proximity NEAR/n ADJn Not possible: use
AND
Standard syntax (considered familiar):
If not: do attend a basic workshop, youtube video, database
documentation (after this workshop)
DEMO

26. Example
Research Question:
Is exercise therapy an effective treatment for hip
osteoarthritis
Elements:
1. Hip osteoarthritis
2. Exercise therapy
3. (Treatment effectiveness)

27. Hip osteoarthritis
()

29. Hip osteoarthritis
(''/exp)
('hip osteoarthritis'/exp)

31. Hip osteoarthritis
('hip osteoarthritis'/exp OR ():ab,ti)
('hip osteoarthritis'/exp OR
(coxarth*):ab,ti)
('hip osteoarthritis'/exp OR (coxarth* OR
(() NEAR/3 ())):ab,ti)

32. Hip osteoarthritis
('hip osteoarthritis'/exp OR (coxarth* OR
((hip OR cox) NEAR/3 (arth* OR
osteoarth*))):ab,ti)
('hip osteoarthritis'/exp OR (coxarth* OR
((hip OR cox) NEAR/3 (arth* OR
osteoarth*)) OR 'malum coxae
senilis'):ab,ti)

33. Exercise therapy

36. Exercise therapy
('kinesiotherapy'/exp OR (kinesiotherap*
OR kinesitherap* OR ((exercis*) NEAR/3
(technique* OR therap* OR
treat*))):ab,ti)

38. Exercise therapy
('kinesiotherapy'/exp OR (kinesiotherap*
OR kinesitherap* OR ((exercis* OR
movement*) NEAR/3 (technique* OR
therap* OR treat* OR isokinet* OR
isomet*)) OR ((muscle*) NEAR/3
(train*))):ab,ti)

39. Treatment effectiveness

42. Treatment effectiveness
('clinical effectiveness'/exp OR
'comparative effectiveness'/exp OR 'cost
effectiveness analysis '/exp OR 'program
cost effectiveness'/exp OR 'program
effectiveness'/exp)

43. Treatment effectiveness
('clinical effectiveness'/exp OR
'comparative effectiveness'/exp OR 'cost
effectiveness analysis '/exp OR 'program
cost effectiveness'/exp OR 'program
effectiveness'/exp OR ():ab,ti)

44. Treatment effectiveness
('clinical effectiveness'/exp OR
'comparative effectiveness'/exp OR 'cost
effectiveness analysis '/exp OR 'program
cost effectiveness'/exp OR 'program
effectiveness'/exp OR (effectiv*):ab,ti)

45. Concept query
('hip osteoarthritis'/exp OR (coxarth* OR ((hip OR
cox) NEAR/3 (arth* OR osteoarth*)) OR 'malum coxae
senilis'):ab,ti) AND ('kinesiotherapy'/exp OR
(kinesiotherap* OR kinesitherap* OR ((exercis* OR
movement*) NEAR/3 (technique* OR therap* OR
treat* OR isokinet* OR isomet*)) OR ((muscle*)
NEAR/3 (train*))):ab,ti) AND ('clinical
effectiveness'/exp OR 'comparative
effectiveness'/exp OR 'cost effectiveness analysis
'/exp OR 'program cost effectiveness'/exp OR
'program effectiveness'/exp OR (effectiv*):ab,ti)
152 hits

47. Step 2 : type code in Word (summary)
• Open an element with ()
• For emtree terms type ''/exp and paste term
• After pasting all emtree terms, type OR ():ab,ti within
that element once for free text words
• Type single word synonyms first
• Type (() NEAR/3 ()) somewhere in the document to
reuse
• Copy (() NEAR/3 ()) into the ():ab,ti part search for
phrase variants
• Untick search as broadly as possible
Next: Step 3  optimization

48. Step 3: optimizing your strategy
Temporarily change the syntax and check words:
Per element, keeping the rest unchanged
1. (emtree) NOT (free text)
2. (free text) NOT (emtree)
Change the full query, subtract the old results
3. replace /exp and /de with /syn
4. replace :ab,ti with :de,ab,ti

49. ('hip osteoarthritis'/exp …) AND
('kinesiotherapy'/exp OR (kinesiotherap* OR
kinesitherap* OR ((exercis* OR movement*
OR motion OR manual) NEAR/3 (technique*
OR therap* OR treat* OR isokinet* OR
isomet* OR water)) OR ((muscle*) NEAR/3
(train*))):ab,ti) AND ('clinical
effectiveness'/exp …)

50. ('hip osteoarthritis'/exp …) AND
('kinesiotherapy'/exp NOT (kinesiotherap*
OR kinesitherap* OR ((exercis* OR
movement* OR motion OR manual) NEAR/3
(technique* OR therap* OR treat* OR
isokinet* OR isomet* OR water)) OR
((muscle*) NEAR/3 (train*))):ab,ti) AND
('clinical effectiveness'/exp …)

52. ('hip osteoarthritis'/exp …) AND
('kinesiotherapy'/exp OR (kinesiotherap* OR
kinesitherap* OR exercis* OR physiotherap*
OR ((movement* OR motion OR manual)
NEAR/3 (technique* OR therap* OR treat*
OR isokinet* OR isomet* OR water)) OR
((muscle*) NEAR/3 (train*))):ab,ti) AND
('clinical effectiveness'/exp …)
267 hits

53. ('hip osteoarthritis'/exp …) AND
('kinesiotherapy'/exp OR (kinesiotherap* OR
kinesitherap* OR exercis* OR physiotherap*
OR ((movement* OR motion OR manual)
NEAR/3 (technique* OR therap* OR treat*
OR isokinet* OR isomet* OR water)) OR
((muscle*) NEAR/3 (train*))):ab,ti) AND
('clinical effectiveness'/exp …)

54. ('hip osteoarthritis'/exp …) AND
((kinesiotherap* OR kinesitherap* OR
exercis* OR physiotherap* OR ((movement*
OR motion OR manual) NEAR/3 (technique*
OR therap* OR treat* OR isokinet* OR
isomet* OR water)) OR ((muscle*) NEAR/3
(train*))):ab,ti) AND ('clinical
effectiveness'/exp …) NOT
'kinesiotherapy'/exp

56. ('hip osteoarthritis'/exp …) AND
('kinesiotherapy'/exp OR exercise/exp OR
physiotherapy/exp OR (kinesiotherap* OR
kinesitherap* OR exercis* OR physiotherap*
OR ((movement* OR motion OR manual)
NEAR/3 (technique* OR therap* OR treat*
OR isokinet* OR isomet* OR water)) OR
((muscle*) NEAR/3 (train*))):ab,ti) AND
('clinical effectiveness'/exp …)
355 hits

57. End Result – Systematic Review
('hip osteoarthritis'/exp OR ((arthritis/de OR osteoarthritis/de)
AND (hip/de OR 'hip pain'/exp)) OR (coxarth* OR ((hip OR cox)
NEAR/6 (arthrit* OR arthrosis* OR arthroses* OR osteoarth* OR
oa)) OR 'malum coxae senilis'):ab,ti) AND ('kinesiotherapy'/exp
OR exercise/exp OR physiotherapy/exp OR 'conservative
treatment'/de OR (kinesiotherap* OR kinesitherap* OR exercis*
OR physiotherap* OR gymnastic* OR ((movement* OR motion
OR manual OR phys* OR conservative* OR nonoperat* OR
nonsurg* OR non-operative OR non-surgical OR paramedic* OR
para-medical) NEAR/3 (technique* OR therap* OR treat* OR
isokinet* OR isomet* OR water OR management* )) OR
((muscle* OR muscul*) NEAR/3 (train*))):ab,ti)
1916 hits

58. Considerations
Explode a broad term or not?
Start exploded, when many irrelevant
results appear, be more specific
Truncate a term or not?
Truncate as much as possible, hardly noise
How broad should proximity be?
Start with 3, increase with 3 and
evaluate newly retrieved articles

59. Important to remember
• Create single line syntax in Word document
• Type code (() ; ‘’/exp; OR ():ab,ti ; (() NEAR/3
()) ) before filling in words
• Copy emtree terms into your document
• Use the synonyms in ():ab,ti, creating
proximity searches from phrases
• Optimize by comparing emtree NOT ab,ti and
the other way around

60. Semi-automatic and fast translation to
other databases

61. E-mail me for more information:
• Roadmap to optimizing queries in
embase.com explaining every step in detail
• Sharing Macros to translate syntax of
embase.com to other databases

62. Contact details
E-mail: w.bramer@erasmusmc.nl
Twitter: @wichor
LinkedIn: nl.linkedin.com/in/wichor
Slideshare: www.slideshare.net/wichor
Meet me in person:
15-20 May MLA conference, Austin, TX (USA)
10-12 June EAHIL workshop, Edinburgh (UK)

63. Further reading:
• Bramer WM, Giustini D, Kramer BM, Anderson PF. The comparative recall
of Google Scholar versus PubMed in identical searches for biomedical
systematic reviews: a review of searches used in systematic reviews. Syst
Rev. 2013 Dec 23;2:115.
• Bramer WM, Holland L, Mollema J, Hannon T, Bekhuis T. Removing
duplicates in retrieval sets from electronic databases: comparing the
efficiency and accuracy of the Bramer-method with other methods and
software packages
• Bramer WM, Pols DHJ, Bindels PJE, Bohnen AM. A fast, reliable and
objective method for creating thematic search filters in bibliographic
databases [in process]
• Work in progress on coverage, retrieval and relevance ranking of the major
databases for systematic reviews

64. Additional topics
• Speed of searches
• Quality of searches
• Success factors
• Why start in embase
• Do you need to understand the topic
• Set numbers or single line queries
• Which databases do you use
• Subheadings
• Interface choice

65. Speed of searches
42%
73%
91%
0%
25%
50%
75%
100%
0 30 60 90 120 150 180
CumulativepercentageofSRs
(N=207)
Minutes needed to create search

66. Proclaimer on speed
• The described method does not guarantee the
speed shown here
• Nor should this be the norm
• Systematic searches (especially for reviews)
should always aim at optimizing sensitivity
• Quality of the search results is what counts
(see the next slide)

67. Quality of searches
(median
values)
Bramer
(N=96-402)
Benchmark
(N=68-93)
Difference
# terms 54 45 21%
# databases 7 3 133%
# hits 2108 1399 51%
# includes 36 19 89%
precision 1,6% 1,2% 29%
Benchmark: All SRs published in 2014 by Dutch university hospitals (not including Erasmus MC)
with a librarian co-author or librarian mentioned in the acknowledgements

68. Success factors
1. Experience (hardly controllable)
2. Interface choice and database order (habit,
and management decision)
3. Optimization techniques (this workshop)
4. Single-line search strategies (habit)
5. Macros (available upon request)
6. The researcher immediately providing
feedback on the results (habit)

69. Why start in embase?
Source: Unpublished research Bramer (4321 included references from 96 reviews)
0% 20% 40% 60% 80% 100%
Google Scholar
Embase
Medline
first 300 first 1000 retrieval coverage citations (GS)

70. Do you need to fully understand the research question?
What is the Cell contribution to chondroid / endochondreal /
intramembranous bone formation
((('bone development'/de OR 'bone mineralization'/de OR 'bone
maturation'/de OR ossification/de OR 'bone conduction'/de OR 'bone
transplantation'/exp OR 'bone matrix'/exp OR 'bone growth'/exp OR
'bone remodeling'/de OR ((bone NEAR/6 (minerali* OR develop* OR
format* OR synthesis* OR growth* OR graft* OR transplant* OR
engineer* OR defect* OR matri* OR remodel* OR conduct* OR maturat*))
OR osteogen* OR ossificat*):ab,ti) AND (chondroid* OR
transchondroid* OR enchondr* OR endochondr* OR intermembran* OR
cartilagin* OR (inter NEXT/1 membran*)):ab,ti) OR 'enchondral
ossification'/de) AND ('cell death'/de OR 'cell survival'/de OR
apoptosis/de OR 'cell differentiation'/de OR 'cell fate'/de OR 'host
cell'/de OR 'cell lineage'/de OR (((cell* OR msc OR osteoblast* OR
osteocyte* OR osteoclast* OR preosteoblast*) NEAR/3 (death OR
senescen* OR contribut* OR differentiat* OR fate OR plasticit* OR
reprogram* OR donor* OR host* OR recruit* OR surviv* OR viabilit* OR
lineage*)) OR apoptosis):ab,ti)

71. Single line approach or set numbers?
Well structured?
#1 brassica/exp
#2 brassica*:ab,ti
#3 broccoli:ab,ti
#4 #1 OR #2 OR #3
#5 neoplasm/exp
#6 neoplas*:ab,ti
#7 cancer*:ab,ti
#8 tumor*:ab,ti
#9 #5 OR #6 OR #7 OR #8
#10 #4 AND #9
#11 [animals]/lim
#12 [humans]/lim
#13 #11 AND #12
#14 #11 NOT #13
#15 #10 NOT #14
Unstructured?
(brassica/exp OR (brassica* OR
broccoli):ab,ti) AND (neoplasm/exp
OR (neoplas* OR cancer* OR
tumor*):ab,ti) NOT ([animals]/lim
NOT [humans]/lim)

72. Single line approach or set numbers?
Disadvantages of set numbers:
1. Optimization is complicated (cannot easily add terms)
2. Repeating a search is difficult and time consuming
3. Translating to other databases is difficult (different
number of thesaurus terms)
Disadvantages of single line approach:
1. Use of many parentheses easily results in errors
 type parentheses before pasting words words
2. You cannot see what a single term does (spot errors)
 because of optimization with NOT errors are easily
recognizable
72

73. When to use what databases?
(N=3661 incl ref) total retrieval unique
embase 2913 80% 470 48%
medline 2529 69% 190 19%
Web-of-Science 1907 52% 187 19%
Google Scholar 1510 41% 88 9%
Other databases 54 5%

74. The databases I use:
Database Used in % of SR
Embase.com 100%
Medline (OvidSP) 98%
(PubMed the other 2%)
Cochrane central 97%
Web-of-Science 94%
PubMed (publisher) 90%
Google Scholar 90%
Scopus 40%
Cinahl 23%
PsycINFO 16%
Other (proquest, sportdiscus,
lilacs, scielo, eric, amed etc)
<3%

75. What to do with subheadings
Separate element
(broccoli/de OR (broccoli* OR
bassica*):ab,ti) AND (neoplasm/exp
OR (cancer* OR neoplas*):ab,ti) AND
(prevention:lnk OR prevention/exp
OR (prevent*):ab,ti)
Combined element
(broccoli/de OR (broccoli* OR
bassica*):ab,ti) AND
(neoplasms/exp/dm_pc OR ‘cancer
prevention’/de OR ((cancer OR
neoplasm) NEAR/3 (prevent*)):ab,ti)
Sensitive
 More hits : 345 (101 unique)
 Less chance of missing relevant
articles
 Recommended for start
 For SRs highly recommended
Specific
 Less hits : 257 (13 unique)
 Higher chance of missing relevant
articles
 To reduce the number of hits
 Use proximity in free text

76. Interface choice
Embase.com
Pros
- Very good relevance ranking
Cons
- Translating between embase
and medline more
complicated
- No wildcard (?) in truncation
- Special characters not
normalized ( )
OvidSP
Pros
- Equal syntax to medline
(OvidSP)
Cons
- No relevance ranking on
complicated queries
- Complex thesaurus interface
My advice: relevance ranking is
very helpful during
optimization. Problems are only
minor. Start in embase.com and
translate with macros