EBP Workshop: RMH November 2012

searching the literaturePeter Greenberg

Physician: Department of General Medicine and Melbourne EpiCentre, The Royal Melbourne Hospital (RMH)

& Honorary Principal Fellow: Schools of Medicine & Population Health, The University of Melbourne

Catherine VoutierClinical Librarian, Health Sciences Library, Royal Melbourne Hospital

searching the literature

• managing clinical research evidence

• evidence based practice (EBP)

• information, knowledge and wisdom

• search techniques and strategies

managing clinical research evidence

information can be pushed or pulled

• pushed: alerts us to information we might need * ‘just in case’ learning: a) lay resources radio; films; television; books; newspapers...... b) professional resources textbooks; journals; e-subscriptions; “e-feeds”....

• pulled: access information when we need it * ‘just in time’ learning: useful whenever questions arise!

evidence-based clinical practice (EBP)

• begins by clarifying patients’ issues, which arise during consultations

• EBP involves a series of ‘steps’:

– asking questions

– seeking answers

– critical appraisal of retrieved literature

– applying data to patients’ problems

– integrating information with the patients’ values

information, knowledge and wisdom

what do literature searches deliver?

• “information”

• “knowledge”

information which is considered and applicable

• “wisdom”

knowledge applied with experience

see “The Rock” by T.S. Eliot (1934) for the difference between information, knowledge and wisdom

more about asking questions

1) what is the question about? therapy? diagnosis? cause? risk? prognosis?……..

2) is the question general (‘background’) or specific for this patient (‘foreground’)?

3) how are questions best structured to facilitate searches for answers?

‘background’ and ‘foreground’ questions• background

* topic (e.g. ‘disease’) orientated * general rather than specific

* begin with: ‘how’; ‘what’; ‘which’; ‘why’; ‘do’; ‘does’….....

• foreground

* patient-problem oriented

* specific* rather then general * structured format

foreground question components become search terms!

‘background’ and ‘foreground’ questions

in reality, there is a continuous spectrum from ‘background’ to

‘foreground’ questions

why structure ‘foreground’ questionsin PICO(T) format?

Patient (Population) Intervention Comparison Outcome Time

1) requires you to consider questions carefully++

2) you can search with some (or all) PICO(T) terms!

3) practice is needed to choose terms which: * precisely address your questions * are not too specific to provide answers

searching the literature• managing clinical research evidence

• evidence based practice (EBP)

• information, knowledge and wisdom

• search techniques and strategies

search techniques

• available e-resources

• MeSH* terms * medical subject heading

• searching ‘secondary’ data sources

• searching ‘primary’ data sources

search techniques available e-resources*

• via “Clinicians Health Channel”

• via Hospital (University or other) library

• via private subscription

• via www at no cost

search techniques available e-resources

• via “Clinicians Health Channel”• via Hospital (University or other) library• via private subscription• via www at no cost* ‘PubMed’ (free ‘Medline’ access)

* The Cochrane Library

* ‘TRIP database’

* ’BMJ/McMaster Evidence Updates’

* ‘TRIP database’

* ’BMJ/McMaster Evidence Updates’

* ‘NHMRC (NICS) Clinical Guidelines Portal ‘

* ‘Google’ & ‘Google Scholar’

search techniques

• available e-resources

• MeSH* terms * medical subject heading

• searching ‘secondary’ sources

• searching ‘primary’ sources

searching with Medical Subject Headings (MeSH) terms

Entry(MeSH) Term: Diabetes Mellitus, Type 1 Diabetes Mellitus, Brittle

Brittle Diabetes Mellitus

Diabetes Mellitus, Insulin-Dependent

Insulin-Dependent Diabetes Mellitus

Diabetes Mellitus, Juvenile-Onset

Juvenile-Onset Diabetes Mellitus

Diabetes Mellitus, Ketosis Prone

Ketosis-Prone Diabetes Mellitus

Diabetes Mellitus, Sudden-Onset

Mellitus, Sudden-Onset Diabetes

Sudden-Onset Diabetes Mellitus

Diabetes Mellitus, Type I

IDDM

Type 1 Diabetes Mellitus

Diabetes, Autoimmune

Autoimmune Diabetes

MeSH

• MEDLINE entries are indexed with ~30,000 thesaurus terms and ~85 sub-headings for sensitive, specific and efficient searching

• MeSH terms * applied to publications as specifically as possible * cover ~106 concepts

• each publication has ~10-20 MeSH terms• MEDLINE# & ‘The Cochrane Library’ have:

* MeSH browsers: which assign ‘MeSH’ to ‘text’ terms * MeSH tree displays * automatic mapping of text to MeSH terms # accessed through ‘PubMed’, ‘EBSCO’ (Clinicians Health Channel); Institute for Scientific Information (ISI): Thompson Scientific. (The University of Melbourne), “OVID”…….

search techniques

• available resources

• MeSH* terms * medical subject heading

• searching ‘secondary’ sources

• searching ‘primary’ sources

search techniques

• ‘secondary’ databases * ‘filtered’ or derived from research publications e.g. ‘critical appraisals’;

comments; summaries; syntheses, texts…. * fewer citations * faster, efficient, easier searching * less sensitive, but more specific searches fewer citations, both relevant and irrelevant

• ‘primary’ databases * original research publications * many citations * harder, slower searching * more sensitive, but less specific searches more citations, both relevant and irrelevant

examples of ‘secondary’ databasescontent example

• evidence summaries

• texts

• systematic reviews

• ‘filtered’ by peers for relevance/importance

• structured abstracts and commentaries

• ‘Clinical Evidence’ see “Best Practice” (CHC)

• CHC resources see ‘Best Practice’ & ‘DynaMed’

• other resources “UpToDate”……...

• ‘Cochrane Reviews’ see ‘The Cochrane Library’

• ‘BMJ/McMaster Evidence Updates’

• ‘ACP* Journal Club’ * American College of Physicians

other secondary sources of evidence

• clinical practice guidelines*: -‘systematically developed statements to assist practitioner (and patient) -decisions about appropriate health care for specific clinical circumstances’

• (integrated) clinical pathways*: “multidisciplinary outlines of anticipated care, placed in an appropriate timeframe, to help a patient with a specific condition or set of symptoms move progressively through a clinical experience to positive outcomes.”

*their value depends on the rigour of the development process

search techniques

• available resources

• MeSH* terms * medical subject heading

• searching ‘secondary’ sources

• searching ‘primary’ sources

search techniques

• ‘primary’ databases * original research publications * many citations * harder, slower searching * more sensitive, but less specific searches more citations, both relevant and irrelevant

• ‘secondary’ databases * ‘filtered’ or derived from research publications e.g. ‘critical appraisals’;

comments; summaries; syntheses, texts…. * fewer citations * faster, efficient, easier searching * less sensitive, but more specific searches fewer citations, both relevant and irrelevant

examples of ‘primary’ databases • ‘MEDLINE’ access:

* ‘PubMed’ * ‘ISI’ Institute for Scientific Information: Thompson Scientific. (The University of

Melbourne.) * ‘EBSCO’ (Clinicians Health Channel) * ‘OVID’……...

• Cochrane Library: “Clinical Trials”

• ‘CINAHL’ Cumulative Index to Nursing and Allied Health Literature

• ‘EMBASE’ Excerpta Medica Database (drugs)

• PsycINFO American Psychological Association (psychological abstracts)

• other…. ?

searching ‘Medline’ (‘PubMed’)some tips

• MeSH browser note

the 2 option boxes below the sub-headings: * “Restrict to MeSH Major Topic” * “Do not include MeSH terms found below this term in the MeSH hierarchy”

• after retrieving publications, check: * “ Search details” to see how the search was undertaken # # truncation

(e.g. Palliat*) removes ‘mapping’ to MeSH terms * “Related citations in PubMed” for additional, relevant citations * “Search History” to combine searches: see “Advanced” * MeSH terms allocated: alternative MeSH terms are displayed beneath citations

• “Clinical Queries” provides efficient, specific searching with “in-built” search filters

• limits or qualifiers avoid these unless absolutely necessary, at the end of search

searching ‘The Cochrane Library’ some tips

• always do a MeSH search as well – type in a single term and locate appropriate MeSH term by clicking on “Thesaurus” button’

– select best term from list

– click on “View Results”

• if searches involve > 1 search term, repeat the above

• combine search results via ‘Search History’

• avoid adding limits or qualifiers until necessary

search strategy depends on…

• what the question is about: therapy, diagnosis, cause, risk……..

• question type: ‘background’, ‘foreground’

• availability of and experience with particular databases

• the purpose of the literature search

– write a paper use primary sources of research data

– systematic review use primary sources of research data

– research project use primary sources of research data

– manage a patient use secondary resources first

• time available secondary sources if there is little time

• prevalence of issue secondary sources for common issues

answering ‘foreground’ questions (1)recommended search strategy for MEDLINE etc

• use ‘PICO(T)’ terms for searching

• determine MeSH (Medical Subject Headings) terms

• search secondary databases. Consider a MeSH search,especially in ‘The Cochrane Library’

• next, search primary databases with search filters such as‘PubMed Clinical Queries’

• search primary databases without search filters. Consider aMeSH search, especially in ‘The Cochrane Library’.

answering ‘foreground’ questions (2)recommended search strategy for MEDLINE etc

• check ‘Related Articles’ and MeSH terms used in key citations

• if you need more results, try different search terms, e-updatedtextbooks*, search engines such as ‘TRIP’ database#, ‘GoogleScholar’, ‘Google’ and other secondary sources of evidence†

* eg ‘BMJ best Practice’, ‘Dynamed’‘UpToDate’# http://www.tripdatabase.com/index.html† eg clinical practice guidelines

• if needed, seek assistance from a skilled librarian

• consider a research project if there is insufficient evidence!

search techniques and strategy summary

• formulate the best PICO(T) question

• use MeSH terms

• use secondary databases first

further reading

• asking questions Straus S, Richardson SR, Glasziou P, Haynes BR. Evidence-Based Medicine. How to practice and

teach EBM. 3rd ed. Elsevier Churchill Livingstone. 2005 Glasziou , Del Mar C. Evidence-based Practice Workbook, 2nd Ed.Blackwell/BMJ Books. 2007 Oxman AD, Sackett DL, Guyatt GH, for the Evidence-Based Medicine Working Group. Users’ guides to

the medical literature: I. How to get started. JAMA 1993:270:2093-2095. Richardson WS, Wilson MC, Nishikawa J, Hayward RSA. The well-built clinical question: a key to

evidence-based decisions. [Editorial]. ACP J Club 1995; 123(3):A12-13 Richardson WS. Ask, and ye shall retrieve. [EBM Note]. Evidence Based Medicine 1998; 3:100-101. Mitchell G. Reframing the question. A way of applying evidence based medicine to a common clinical

situation. Aust Fam Physician 1998; 27:875-6. Stone PW. Popping the (PICO) question in research and evidence-based practice. Appl Nurs Res

2002; 15:197-8. Onady GM, Raslich MA. Evidence-based medicine: asking the answerable question (question

templates as tools). Pediatr Rev 2003; 24:265-268. Southern Health Centre for Clinical Effectiveness: Evidence-Based Answers to Clinical Questions for

Busy Clinicians. Workbook 2009 http://www.southernhealth.org.au/icms_docs/2145_EBP_workbook.pdf

‘Asking focused questions”. Centre for Evidence-Based Medicine Oxford(UK) http://www.cebm.net/index.aspx?o=1036http

An interactive tool from the Centre for Evidence Based Medicine Toronto http://ktclearinghouse.ca/cebm/practise/formulate

further reading

• searching the literature for answers Straus S, Richardson SR, Glasziou P, Haynes BR. Evidence-Based Medicine. How to practice

and teach EBM. 3rd ed. Elsevier Churchill Livingstone. 2005 Glasziou , Del Mar C. Evidence-based Practice Workbook, 2nd Ed.Blackwell/BMJ Books. 2007 “Help” and “Tutorials” sections within e-databases JAMA ‘Users’ guides’ series. Oxman AD, Sackett DL, Guyatt GH, for the Evidence-Based

Medicine Working Group. Users’ guides to the medical literature: I. How to get started. JAMA. 1993;270:2093-2095

Greenhalgh T. How to read a paper: the basics of Evidence-based Medicine. BMJ, London.1997 Ebbert JO, Dupras DM, Erwin PJ. Searching the medical literature using PubMed: a tutorial.

Mayo Clin Proc.2003; 78:87-91). Robinson A, Day S. The value of PubMed and HighWire Press for the busy general practitioner.

Australian Prescriber 2004; 27(Number 1):16-18. Sood A, Erwin PJ, Ebbert JO. Using advanced search tools on PubMed for citation retrieval.

Mayo Clin Proc 2004; 79:1295-1300. Giustini G. How Google is changing medicine. BMJ 2005; 331:1487-1488 Steinbrook R. Searching for the right search -Reaching the medical literature. N Eng J Med

2006; 354:4-7 Tank H, Ng JHK. Googling for a diagnosis-use of Google as a diagnostic aid: internet based

study. BMJ 2006; 333:1143-1145