Evidence Based MedicineEvidence Based Medicine
Dr. Judith MeehanDepartment of Paediatrics
How do we make clinical How do we make clinical decisions?decisions?
Toss coins Guess "Do no harm." (Hippocrates) Ask colleagues Text books? Browse journals Searching bibliographic databases
Clinicians Clinicians really really need need information!information!
If shadowed: we need it up to 60 times per week
(twice per every three patients), and it could affect eight decisions per day.
but we get only 30% of it, and that comes from passers-by
– “my textbooks are out of date”– “my journals too disorganised”– “library too far away”
How many minutes a week How many minutes a week did you spend last week did you spend last week
reading around your reading around your patients?patients?
Medical students
Interns
SHOs
SpRs
Consultants
How many minutes a week How many minutes a week did you spend last week did you spend last week
reading around your reading around your patients?patients?
Medical students
120mins
Interns
SHOs
SpRs
Consultants
How many minutes a week How many minutes a week did you spend last week did you spend last week
reading around your reading around your patients?patients?
Medical students
120mins
Interns 10mins
SHOs
SpRs
Consultants
How many minutes a week How many minutes a week did you spend last week did you spend last week
reading around your reading around your patients?patients?
Medical students
120mins
Interns 10mins
SHOs 30mins
SpRs
Consultants
How many minutes a week How many minutes a week did you spend last week did you spend last week
reading around your reading around your patients?patients?
Medical students
120mins
PRHOs 10mins
SHOs 30mins
SpRs 45mins
Consultants
ICHMT
Log Book
How many minutes a week How many minutes a week did you spend last week did you spend last week
reading around your reading around your patients?patients?
Medical students
120mins
PRHOs 10mins
SHOs 30mins
SpRs 45mins
Consultants 60mins
The inevitable The inevitable consequenceconsequence
On average, the clinically-important knowledge of physicians deteriorates rapidly after we complete our training
The Slippery SlopeThe Slippery SlopeThe Slippery SlopeThe Slippery Slope
years since graduation
r = -0.54p<0.001
...
...
. ... . .... .
....
....
.....
...knowledgeof current best care
Three solutions Three solutions Clinical performance can keep up to date:1. by learning how to practice evidence-
based medicine ourselves.2. by seeking and applying evidence-
based medical summaries generated by others.
3. by accepting evidence-based practice protocols developed by our colleagues.
What Is Evidence Based What Is Evidence Based Medicine?Medicine?
The conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients
What Is Evidence Based What Is Evidence Based Medicine?Medicine?
The practice of EBM requires the integration of individual clinical expertise
with the
best available external clinical evidence from systematic research
WHAT ARE THE IMPORTANT WHAT ARE THE IMPORTANT ELEMENTS OF EBM?ELEMENTS OF EBM?
‘EBM begins and ends with patients’
1) Convert patient health care needs into
answerable questions.
2) Track down the best evidence.
3) Critically appraise evidence.
4) Apply the results into clinical practice.
5) Evaluate your performance.
ASK CLINICAL QUESTIONS ASK CLINICAL QUESTIONS THAT YOU CAN ANSWERTHAT YOU CAN ANSWER
‘Answerable questions are the backbone of practising EBM’
In practice, good questions usually include:- ( PICO)
Patient’s clinical needsIntervention(s)comparison / Interventionclinical Outcome(s)
Practical EBMPractical EBM
1. Understand the kinds of questions you ask and want answered at the point-of-care.
2. Select trusted EBM data sources that will most likely provide usable answers for you.
Your Clinical QuestionsYour Clinical Questions
Write down one recent patient problem
What was the critical question?
Did you answer it? If so, how?
Scenario 1Scenario 1
In the middle of the night you are called to see a screaming, febrile 3 yo with acute otitis media. You ask yourself, “Should I prescribe antibiotics or not?”. What outcomes are you hoping to achieve by treating the child?– Reduce pain?– Control fever?– Prevent complications?– Reduce parental anxiety?
Which is the most important?
Scenario 1Scenario 1
You also need to consider possible side effects of treatment – antibiotics cause diarrhoea, voniting, allergic reactions and contribute to drug resistance.
You decide that pain reduction is the most important outcome.
Here is your answerable question:– In young children with acute otitis media (population)– does antibiotic treatment compared with no
antibiotics (intervention / comparison)– reduce pain (outcome)
AnswerAnswer
A systematic review of six randomised controlled trials showed no pain reduction within 24 hrs, but a 7% reduction in pain after 2 –7 days (assuming 80% resolve spontaneously with no treatment)
Selecting Evidence Selecting Evidence ResourceResource
Electronic databases - Medline ( Pubmed, OVID) - EMBASE - CINAHL - Cochrane Library Online Journals Internet – Google, Yahoo, Lycos etc.
– rich source of medical information but need to exercise care, not all is‘’peer-reviewed’’
Textbooks – basic info but often ‘’out of date’’ by the time of publication
Sources of InformationSources of Information
Drugs: handbooks, formulariesTreatment textbooks, review articles,guidelines Diagnosis: diagnostic aids, experts, decision algorithms, atlases etc.
Sources of Pre-Appraised Sources of Pre-Appraised ResearchResearch
Clinical Evidence Evidence Based journals
– Evidence Based Medicine, Nursing, Mental Health etc
Systematic reviews– Cochrane Library (via NeLH)
Cochrane Database of Systematic Reviews DARE - Database of Abstracts of Reviews
of Effectiveness
www.nelh.nhs.uk/cochrane.asp
Resources available Resources available through TCDthrough TCD
Evidence Based MedicineACP Journal ClubOVIDMany online paediatric journals: Archives of Disease in Children, Journal of Pediatrics Pediatrics Clinical Pediatrics
University Based University Based ResourcesResources
Pediatric Evidence Based Medicine homepage
http://students.washington.edu/garrison/garrison/
GeneralPediatrics.com (U. Iowa):– http://www.generalpediatrics.com
Problem-based resources Harriet Lane Links (Johns Hopkins):
– http://www.harrietlane.org Reviewed resources from the WWW
Healthlinks ( University of Washington)– EBP Tools– http://healthlinks.washington.edu/ebp/ebptools.html
Hierarchy of EvidenceHierarchy of Evidence
Level 1: Systematic ReviewLevel 2: Meta- analysisLevel 3: Randomised Control TrialLevel 4: CohortLevel 5: Case-controlLevel 6: Cross-sectionalLevel 7: Expert Opinion
Systematic reviewsSystematic reviews Reviews that look, in a systematic way,
at all the available research on a topic
Systematic reviews have a clear method - like original research
Critically appraise each piece of research they include
Reliable information for practice
GuidelinesGuidelines
Clinical Practice Guidelines may be– Evidence-based– Research-based (highly referenced)– Opinion-based– “expert consensus”
• Available from numerous sites, useful ones are the American Academy of Pediatrics website
• National Clearing House Guidelines
Critical AppraisalCritical Appraisal
Basic questions when reading a paper– Is it interesting? (Title, Abstract)– Why was it done? ( Introduction)– How was it done? (Methods)– What has it found? (Results)– What are the implications?
(Abstract ,Discussion)– What else is of interest? (Discussion)
Take Home MessageTake Home Message
Formulate clinical questions before you start Use existing reviews, appraised evidence Use checklists as a prompt in your own critical
appraisal Just because it’s published doesn’t mean it’s
right Critical appraisal is a tool for assessing validity Help and examples are available
– Books,– Checklists ( Consort, Crosbie, Greenhalgh)– EBM internet sites