1. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
Systematic Literature Reviews:
A 'How To' Guide
Isla Kuhn
Reader Services Librarian
Medical Library

2. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
Question
Scoping
search
Full
search
Title and
abstract
screening
Full text
screening
Additional
searching
Included
references
agreed
Data
extraction
Synthesis
Writing up
Reference
management
Protocol
Update
search
Full text
retrieval

3. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
Question
Scoping
search
Full
search
Title and
abstract
screening
Full text
screening
Additional
searching
Included
references
agreed
Data
extraction
Synthesis
Writing up
Reference
management
Protocol
Update
search
Full text
retrieval

4. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
• how to clarify the question (or perhaps questions) on which you need to find
literature
• selecting the databases and other resources you will need to search
• devising the most comprehensive literature search strategy so you know
you’ve not missed any relevant studies
• keeping up to date with new information appearing between the initial search
and write-up
• issues around management of process and results
• management of references (using software such as EndNote), and getting
hold of the full text article

5. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
• What are the key elements in the systematic review process?
What do you understand by
„systematic review‟?

6. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
“A systematic review attempts to identify, appraise and synthesise all the empirical
evidence that meets pre-specified eligibility criteria to answer a given research
question. Researchers conducting systematic reviews use explicit methods aimed at
minimising bias, in order to produce more reliable findings that can be used to inform
decision making” (Cochrane)
“Systematic reviews aim to find as much as possible of the research relevant to
the particular research questions, and use explicit methods to identify what can reliably
be said on the basis of these studies. Methods should not only be explicit but
systematic with the aim of producing varied and reliable results”. (EPPI)
“A systematic review uses transparent procedures to find, evaluate and synthesize the
results of relevant research. Procedures are explicitly defined in advance, in order to
ensure that the exercise is transparent and can be replicated. This practice is also
designed to minimise bias” (Campbell)
What is a “systematic review”?
Does not mean quick!

7. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
• Critical review
• Literature review
• Mapping review/systematic map
• Meta-analysis
• Mixed studies/mixed methods review
• Overview
• Qualitative systematic review/qualitative evidence
synthesis
• Rapid review
• Scoping review
Grant, MJ & Boothe, A. A typology of reviews: an analysis of 14
review types and associated methodologies. Health Information and
Library Journal 26(2), 91-108. 2009
Types of review
• State-of-the-art review
• Systematic review
• Systematic search and review
• Systematized review
• Umbrella review
• Umbrella review

8. CAMBRIDGE UNIVERSITY LIBRARY
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Systematic review Literature review
Question Focused on a single question. Not necessarily focused on a single
question, but may describe an overview.
Protocol A peer review protocol or plan is included. No protocol is included.
Background Both provide summaries of rationale to the review.
Objectives Clear objectives are identified Objectives may or may not be identified
Study inclusion and
exclusion criteria
Criteria stated before the review is conducted Criteria often not specified.
Search strategy Comprehensive search conducted in a
systematic way.
Strategy not explicitly stated.
Process of selecting
articles
Usually clear and explicit and involve double
screening
Not described in a literature review.
Process of evaluating
articles
Comprehensive evaluation of study quality. Evaluation of study quality
may or may not be included.
Results and data
synthesis
Clear summaries of studies taking into account
quality of evidence.
Summary based on studies where the quality of
articles may not be specified. May also be
influenced by the reviewer’s theories, needs
and beliefs.
Bias & replicability Minimises publication and selection bias and
review can easily be reproduced
Open to bias and difficult to repeat the review
Adapted from : Bettany-Saltikov J (2010) Learning how to undertake a
systematic review: part 1. Nursing Standard. 24, 50, 47-55. Date of
acceptance: October 26 2009
Systematic vs Literature Review

9. CAMBRIDGE UNIVERSITY LIBRARY
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http://onlinelibrary.wiley.com/doi/10.1002/146518
58.CD004333.pub3/abstract

10. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
#1 Accidents/
#2 exp Accidents, Traffic/
#3 exp Accident Prevention/
#4 exp Motorcycles/
#5 motor-cycl* or motorcycl* or motor-bik* or motorbik* or scooter* or moped* or moto
or motocycl* or motocicl*
#6 trauma* or injur* or fatal* or accident* or crash* or prevent* or collide* or collision*
#7 #1 or #2 or #3 or #4 or #5 or #6
#8 head near protect*
#9 head near shield*
#10 helmet*
#11 exp Head Protective Devices/
#12 #8 or #9 or #10 or #11
#13 #7 and #12

11. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
1 clinical trial.pt.
2 randomized.ab,ti.
3 placebo.ab,ti.
4 dt.fs.
5 randomly.ab,ti.
6 trial.ab,ti.
7 groups.ab,ti.
8 or/1-7
9 Animals/
10 Humans/
11 9 not (9 and 10)
12 8 not 11
13 dorsalgia.ab,ti.
14 exp Back Pain/
15 exp Low Back Pain/
16 backache.ab,ti.
17 (lumbar adj pain).ab,ti.
18 coccyx.ab,ti.
19 coccydynia.ab,ti.
20 exp Sciatica/
21 sciatica.ab,ti.
22 spondylosis.ab,ti.
23 lumbago.ab,ti.
24 or/13-23
25 exp Spine/
26 discitis.ab,ti.
27 exp Spinal Diseases/
28 (disc adj degeneration).ab,ti.
29 (disc adj prolapse).ab,ti.
30 (disc adj herniation).ab,ti.
31 spinal fusion.sh.
32 spinal neoplasms.sh.
33 (facet adj joints).ab,ti.
34 intervertebral disk.sh.
35 postlaminectomy.ab,ti.
36 arachnoiditis.ab,ti.
37 (failed adj back).ab,ti.
38 or/25-37
39 exp activities of daily living/
40 activities of daily living.tw.
41 day to day activ$.ti,ab.
42 daily activit$.ti,ab.
43 ordinary activit$.ti,ab.
44 normal activit$.ti,ab.
45 stay$ active.ti,ab.
46 exp Bed Rest/
47 bed rest.mp.
48 or/39-47
49 24 or 38
50 12 and 49
51 48 and 50

12. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYFrom topic to search
introducing the research topic
• clarifying the question
• setting parameters (inclusion/exclusion criteria not built into
search?)
lose marks through sloppy references
Question
Keywords
Synonyms
MeSH / Subject Headings / sub headings
Boolean Logic
Truncation / wildcards
Limits

13. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYFrom topic to search
• Topic -> question -> keywords/synonyms
Diabetes, especially the impact of patient education …..
”Is patient education effective in improving blood sugar control
in teenage diabetics?”
…………………keywords???.... synonyms???........................
Themes?

14. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
”Is patient education effecting in improving blood sugar control
in teenage diabetics?”
1 – teenagers
2 – patient education
3 – blood sugar
From topic to search
Synonyms?
PICO ?
Patient/Problem/Population
Intervention
Comparison
Outcome
(time?)

15. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
”Is patient education effecting in improving blood sugar control
in teenage diabetics?”
1 – teenagers teens adolescents
2– patient education patient information
3 – blood sugar blood glucose hypoglycaemia hyperglycaemia
From topic to search

16. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYBoolean Logic
AND – to narrow the search by combining different topics
eg
“teenage” and “patient education”
Both terms must be present in the results.
teenage
patient
education

17. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYBoolean Logic
OR – to broaden your search, by combining similar terms
eg
“teenage” or “adolescent”
Either term can be present in the resulting set of articles.
teenage adolescent

18. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYBoolean Logic
NOT – to restrict your search so that it does not contain a particular term
eg
Hypoglycaemia NOT hyperglycaemia
The first, but not the second, term must be present.
hypoglycaemia hyperglycaemia

19. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
”Is patient education effecting in improving blood sugar control
in teenage diabetics?”
teenagers OR teens OR adolescents
AND
patient education OR patient information
AND
blood sugar OR blood glucose OR hypoglycaemia OR hyperglycaemia
From topic to search

20. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYQuestion:
1st theme OR OR OR
AND
2nd theme OR OR OR
AND
3rd theme OR OR OR
AND
4th theme? OR OR OR

21. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYMind map your question?
Research
question
1st
theme
4th
theme
3rd
theme
2nd
theme
synonym
synonym
synonym
synonym
synonym
synonym
synonym
synonym
synonym
synonym synonym
synonym

22. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYTruncation
treat
treats
treating
treated
treater
treatment
treatments
• Treat*
• Treat?
• Treat$
Treatment

23. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
Truncation / wildcards?
1 – teenagers OR teens OR adolescents
AND
2 – patient education OR patient information
AND
3 – blood sugar OR blood glucose OR hypoglycaemia OR hyperglycaemia
From topic to search

24. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYTask
• Go to http://tinyurl.com/embase
• Click through to open EMBASE
• Using advance search, type a key word
(untick “map to subject heading”)
• How many hits?
• Type the keyword with some truncation (use *)
• How many hits?

25. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYFrom topic to search
• Where in the article record do you want the terms/keywords to appear?
• Title?
• Abstract?
• All/any field?
• Impact on sensitivity/specificity?

26. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYTask
• In EMBASE
• Type a key word, and search by “keyword”
• How many hits?
• Type a keyword and search by “title”
• How many hits?

27. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY

28. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
http://www.ncbi.nlm.nih.gov/p
ubmed/20144404

29. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYTask - EMBASE
• Type in a keyword, tick “map to subject heading”
Relevant match? Select & explode
How many hits?
• Type in same keyword, tick “map to subject heading”
Relevant match? Select & explode
How many hits?
• Type in same keyword, tick “map to subject heading”
Relevant match? Select & focus
How many hits?

30. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
MeSH
1 – teen* OR adolesce* OR exp"Adolescent“/
AND
2 – patient education OR patient information OR exp”Patient Education as
Topic“/
AND
3 – blood sugar OR blood glucose OR hypoglycae* OR hyperglyca* OR
exp”Blood Glucose“/ OR exp"Hypoglycemia“/
From topic to search

31. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
Inclusion / exclusion criterion?
teen* OR adolesce* OR exp"Adolescent“/
AND
patient education OR patient information OR exp”Patient Education as Topic“/
AND
blood sugar OR blood glucose OR hypoglycae* OR hyperglyca* OR exp”Blood Glucose“/ OR
exp"Hypoglycemia“/
From topic to search
Year of publication? Humans vs Animals?
Type of publication? Language of publication?

32. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
1 teen*
2 adolesce*
3 exp"Adolescent“/
4 1 or 2 or 3
5 patient education
6 patient information
7 exp”Patient Education as
Topic“/
8 5 or 6 or 7
9 blood sugar
10 blood glucose
11 hypoglycae*
12 hyperglyca*
13 exp”Blood Glucose“/
14 exp"Hypoglycemia“/
15 9 or 10 or 11 or 12 or 13 or 14
16 4 and 8 and 15

33. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
1 clinical trial.pt.
2 randomized.ab,ti.
3 placebo.ab,ti.
4 dt.fs.
5 randomly.ab,ti.
6 trial.ab,ti.
7 groups.ab,ti.
8 or/1-7
9 Animals/
10 Humans/
11 9 not (9 and 10)
12 8 not 11
13 dorsalgia.ab,ti.
14 exp Back Pain/
15 exp Low Back Pain/
16 backache.ab,ti.
17 (lumbar adj pain).ab,ti.
18 coccyx.ab,ti.
19 coccydynia.ab,ti.
20 exp Sciatica/
21 sciatica.ab,ti.
22 spondylosis.ab,ti.
23 lumbago.ab,ti.
24 or/13-23
25 exp Spine/
26 discitis.ab,ti.
27 exp Spinal Diseases/
28 (disc adj degeneration).ab,ti.
29 (disc adj prolapse).ab,ti.
30 (disc adj herniation).ab,ti.
31 spinal fusion.sh.
32 spinal neoplasms.sh.
33 (facet adj joints).ab,ti.
34 intervertebral disk.sh.
35 postlaminectomy.ab,ti.
36 arachnoiditis.ab,ti.
37 (failed adj back).ab,ti.
38 or/25-37
39 exp activities of daily living/
40 activities of daily living.tw.
41 day to day activ$.ti,ab.
42 daily activit$.ti,ab.
43 ordinary activit$.ti,ab.
44 normal activit$.ti,ab.
45 stay$ active.ti,ab.
46 exp Bed Rest/
47 bed rest.mp.
48 or/39-47
49 24 or 38
50 12 and 49
51 48 and 50

34. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
1 clinical trial.pt.
2 randomized.ab,ti.
3 placebo.ab,ti.
4 dt.fs.
5 randomly.ab,ti.
6 trial.ab,ti.
7 groups.ab,ti.
8 or/1-7
9 Animals/
10 Humans/
11 9 not (9 and 10)
12 8 not 11
13 dorsalgia.ab,ti.
14 exp Back Pain/
15 exp Low Back Pain/
16 backache.ab,ti.
17 (lumbar adj pain).ab,ti.
18 coccyx.ab,ti.
19 coccydynia.ab,ti.
20 exp Sciatica/
21 sciatica.ab,ti.
22 spondylosis.ab,ti.
23 lumbago.ab,ti.
24 or/13-23
25 exp Spine/
26 discitis.ab,ti.
27 exp Spinal Diseases/
28 (disc adj degeneration).ab,ti.
29 (disc adj prolapse).ab,ti.
30 (disc adj herniation).ab,ti.
31 spinal fusion.sh.
32 spinal neoplasms.sh.
33 (facet adj joints).ab,ti.
34 intervertebral disk.sh.
35 postlaminectomy.ab,ti.
36 arachnoiditis.ab,ti.
37 (failed adj back).ab,ti.
38 or/25-37
39 exp activities of daily living/
40 activities of daily living.tw.
41 day to day activ$.ti,ab.
42 daily activit$.ti,ab.
43 ordinary activit$.ti,ab.
44 normal activit$.ti,ab.
45 stay$ active.ti,ab.
46 exp Bed Rest/
47 bed rest.mp.
48 or/39-47
49 24 or 38
50 12 and 49
51 48 and 50

35. CAMBRIDGE UNIVERSITY LIBRARY
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Advice to rest in bed versus advice to stay active for acute
low-back pain and sciatica
The objective of this review is to determine the effects of advice to rest in bed or stay active for patients
with acute low-back pain or sciatica.
The following comparisons will be made:
• Bed rest versus staying active
• Bed rest versus other treatments (besides staying active)
• Shorter periods of bed rest versus longer periods of bed rest
• Staying active versus other treatments (besides bed rest)
• Comparison between different forms of advice to stay active (e.g. avoiding bedrest, staying active)
http://mrw.interscience.wiley.com/cochrane/clsysrev/articles/CD007612/pdf_fs.html

36. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
From topic to search:
same strategy, different words
Moving from one database to another…..

37. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
From topic to search:
same strategy, different words
• http://www.sign.ac.uk/methodology/filters.html Observational Study Filters
Medline (via OVID)
1 Epidemiologic studies/
2 Exp case control studies/
3 Exp cohort studies/
4 Case control.tw.
5 (cohort adj (study or studies)).tw.
6 Cohort analy$.tw.
7 (Follow up adj (study or studies)).tw.
8 (observational adj (study or studies)).tw.
9 Longitudinal.tw.
10 Retrospective.tw.
11 Cross sectional.tw.
12 Cross-sectional studies/
13 Or/1-12
Embase (via OVID)
1 Clinical study/
2 Case control study
3 Family study/
4 Longitudinal study/
5 Retrospective study/
6 Prospective study/
7 Randomized controlled trials/
8 6 not 7
9 Cohort analysis/
10 (Cohort adj (study or studies)).mp.
11 (Case control adj (study or studies)).tw.
12 (follow up adj (study or studies)).tw.
13 (observational adj (study or studies)).tw.
14 (epidemiologic$ adj (study or studies)).tw.
15 (cross sectional adj (study or studies)).tw.
16 Or/1-5,8-15

38. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
From topic to search:
same strategy, different words
• http://www.sign.ac.uk/methodology/filters.html Observational Study Filters
Medline (via OVID)
1 Epidemiologic studies/
2 Exp case control studies/
3 Exp cohort studies/
4 Case control.tw.
5 (cohort adj (study or studies)).tw.
6 Cohort analy$.tw.
7 (Follow up adj (study or studies)).tw.
8 (observational adj (study or studies)).tw.
9 Longitudinal.tw.
10 Retrospective.tw.
11 Cross sectional.tw.
12 Cross-sectional studies/
13 Or/1-12
Medline (via Pubmed)
#1 “Epidemiologic studies”[Mesh]
#2 “case control studies”[Mesh]
#3 “cohort studies”[Mesh]
#4 Case control[Text Word]
#5 (cohort stud*))[Text Word]
#6 Cohort analy*[Text Word]
#7 (Follow up AND (study or studies))[Text Word]
#8 (observational AND (study or studies))[Text
Word]
#9 Longitudinal[Text Word]
#10 Retrospective[Text Word]
#11 Cross sectional[Text Word]
#12 “Cross-sectional studies”[Mesh]
#13 #1 OR #2 OR #3 OR #4 OR #5 OR #6 OR
#7 OR #8 OR #9 OR #10 OR #11 OR #12

39. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYKeywords
introducing the research topic
reviewing relevant literature
• identifying keywords and synonyms and MeSH
• structuring your search strategy with boolean logic
References
• DON‟T plagiarise!
• Don‟t lose marks through sloppy references

40. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYSensitivity vs Specificity

41. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYSensitivity vs Specificity

42. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYSensitivity vs Specificity

43. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
introducing the research topic
reviewing relevant literature
Identify relevant sources (and then search them!)
databases?
websites?
hand searching?
snowballing?
books?
grey literature?
ongoing trials?
• http://www.lib.cam.ac.uk/electronicresources/
• Google? Search by Organisation
• Which journals are key to your work?
• WoK or Scopus
• LibrarySearch or COPAC or GoogleBooks
• Google: blog search; SIGLE; conference
proceedings
• Trials registers

44. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
introducing the research topic
reviewing relevant literature
Identify relevant sources (and then search them!)
References & PDFs
• Critically appraising
• managing
• storing
• using them (cite while you write)
• Data extraction
CASP http://www.casp-uk.net
“How to read a paper” Trish
Greenhalgh
WB 18.343 – in the Medical Library
or http://tinyurl.com/bmj-trish
Zotero
Mendeley
EndnoteWeb
Endnote
Reference Manager
RefWorks
Papers
Pdf xchange

45. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
Question
Scoping
search
Full
search
Title and
abstract
screening
Full text
screening
Additional
searching
Included
references
agreed
Data
extraction
Synthesis
Writing up
Reference
management
Protocol
Update
search
Full text
retrieval

46. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
introducing the research topic
reviewing relevant literature
Identify relevant sources (and then search them!)
References
Keeping up to Date
• alerts
• journal TOCs
• citation tracking
Email alerts
RSS fees

47. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
introducing the research topic
reviewing relevant literature
Identify relevant sources (and then search them!)
References
Keeping up to Date
Management of process and results – more info on data management
• What is the data you need to record?
• Where will you record it? Where will you store it?
• How will you record it?
• How will you share it?
When should all this start?
PRISMA

48. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
introducing the research topic
reviewing relevant literature
Identify relevant sources (and then search them!)
References
Keeping up to Date
Management of process and results
Writing Up
• what did you actually do?
• and where did you do it? (750 words?)
• Search log/diary
• Results matrix
• Tidying up your strategy
• What did you find, where?
• Explicit criterion = reproducable methodology
PRISMA

49. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
http://jech.bmj.com/content/61/12/1069.full.pdf
http://www.bmj.com/content/328/7446/991.full.pdf
PRISMA

50. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYBooks that might help
• http://search.lib.cam.ac.uk/?itemid=|cambrdgedb|1258728
http://search.lib.cam.ac.uk/?itemid=|cambrdgedb|317470
http://search.lib.cam.ac.uk/?itemid=|cambrdgedb|4750307
http://search.lib.cam.ac.uk/?itemid=|cambrdgedb|5651706

51. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYStopping
• Repetition
• Change in ratio of “good” : ”bad” articles retrieved
• Boundaries/Parameters?
• Databases are not infinite:
• if your strategy is good enough,
and your current awareness strategy is in place, trust it, and stop.

52. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY

53. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARY
http://tinyurl.com/2013-sysrev

54. CAMBRIDGE UNIVERSITY LIBRARY
MEDICAL LIBRARYHelp!
Isla Kuhn
Reader Services Librarian
Medical Library
Box 111
Addenbrooke’s Hospital
Thank you.
email: ilk21@cam.ac.uk
twitter: @ilk21
phone: (01223) (3)36750
web: http://library.medschl.cam.ac.uk