Transcript patient or problem

Evidence-Based Practice
奇美醫學中心 林宏榮
What evidence-based medicine is:
“Evidence-based medicine is the
integration of best research evidence with
clinical expertise and patient values”
-
Sackett, et al 2001
What evidence-based medicine is
Patient
Values
Clinical
Expertise
Best
Evidence
Rule 31 –
Review the World Literature Fortnightly*
*"Kill as Few Patients as Possible" - Oscar London
5,000?
per day
Medical Articles per Year
2500000
2000000
1500000
1000000
500000
55 per
day
1,400
per day
0
Trials
MEDLINE
BioMedical
Managing Information
The Airline industry
Boeing 777 manuals
24 binders
10 feet shelf space
Conversion to CD
Reduced search by 60%
The Health Industry
Memorize “the manuals”
Exams, audits, etc to check
Systematic review of bed rest
after medical procedures
10 trials of bed rest after spinal puncture
no change in headache with bed rest
Increase in back pain
Protocols in UK neurology units - 80% still
recommend bed rest after LP
Serpell M, BMJ 1998;316:1709–10
…evidence of harm available for 17 years
preceding...
Allen, Glasziou, Del Mar. Lancet, 1999
Getting Evidence in to Practice
How do you “do” EBP?
What EBP do you do/help with?
What other EBP do you know of?
Compare with you neighbour
Teaching Tip:
Special
background
for activities.
Managing Information
“Push” and “Pull” methods
“Push” - alerts us to new information
“Just in Case” learning
Use ONLY for important, new, valid research
“Pull” – access information when needed
“Just in Time” learning
Use whenever questions arise
EBM Steps: Question; search; appraise; apply
Bimonthly “just in case” journal
Valid, Relevant & (almost) No Effort!
 80 journals scanned
 Is it valid?
 Intervention: RCT
 Prognosis: inception cohort
 Etc
 Is it relevant?
 GPs & specialists ask:
Will this change your practice?
www.evidence-basedmedicine.com
“Just in Time” learning:
Doctor’s information needs
Setting: 64 residents at 2 New Haven hospitals
Method: Interviewed after 401 consultations
Questions
Asked 280 questions (2 per 3 patients)
Pursued an answer for 80 questions (29%)
Not pursued because
Lack of time
Forgot the question
Sources of answers
Textbooks (31%), articles (21%), consultants (17%)
Green, Am J Med 2000
Doctor’s information needs
Most of our questions are NEVER
answered
When answered, the information is likely
to be neither the best nor up-to-date
Step #1
Developing an
answerable Clinical
Question
Your Clinical Questions
Write down one recent patient problem
What was the critical question?
Did you answer it? If so, how?
Good questions
Important to your practice
Important to your patients
Specific
Answerable!
Good Questions
Which patients is this question about?
What is the main intervention?
Is there an alternative intervention?
What can I hope to accomplish?
“Hunting” questions - “PICO”:
“P” - patient or problem
“I” - intervention (e.g., diagnostic test,
treatment, cause, prognostic
factor)
“C” - comparison intervention
(if necessary)
“O” - outcome
Examples of good questions
In patients with insulin-dependent
diabetes mellitus
receiving current standard insulin
therapy
will an intensive insulin regime
reduce the risk of developing
microvascular complications
Examples of good questions
Among women in premature labour
expected to deliver before thirty weeks of
gestation
does an intensive corticosteroid regime
compared with the standard regime
reduce the risk of RDS in their babies?
Information “pull”
Steps in EBM process
1. Formulate an answerable question
2. Track down the best evidence
3. Critically appraise the evidence
4. Integrate with clinical expertise and patient
values
An example: “the first sign of
hyperkalaemia is death”
An anxious laboratory technician phoned about
a potassium of 7.3 mmol/l (Ref Range 3.5-5.0)
found on a routine blood test of a 50 year old
woman.
I arranged an urgent repeat of the electrolytes
(to rule out a spurious elevation) and an ECG.
The latter was reassuringly normal, but left me
asking: Does a normal ECG rule out a serious
elevation of potassium?
1. The question
Does a normal ECG rule out a serious
elevation of potassium?
Population - In suspected hyperkalemia
Indicator - does a normal ECG
Comparator Outcome - rule out hyperkalemia?
1. The question
Does a normal ECG rule out a serious
elevation of potassium?
Population – hyperkal*
Indicator – ECG OR EKG
Comparator Outcome – hyperkal*
Underline keywords; think of synonyms
Step #2
Efficiently track down the
best evidence to
answer clinical questions
Useful data sources
MEDLINE
Cochrane Library
Clinical Evidence
searchable
through
Medline
searchable
together
searchable
individually
Using the tools
NLM (who make Medline) index
thousands of medical journals
Each article is given keywords Major MESH terms
Minor MESH terms
The article title and abstract are also
searchable - as Textwords
Using the tools
Search engines will sometimes match
your entry to the nearest MESH term.
Sometimes they don’t
Experiment!
Filters
A filter is a sequence of Medline search
instructions intended to locate specific
types of study design
Filters exist for
clinical trials
studies of prognosis
studies of adverse effects
and many others….
Filters
Some search engines provide
prepackaged filters
PubMed for example
Most don’t
PubMed via
Google
Diagnosis
button
“OR” synonyms
* Means
any letters
Diagnosis
button
Sensitivity of
62% or 55%
Limit to
EBM Reviews
Most
Recent Update
Step #3
Appraising the
evidence for
validity
The “best” evidence depends on the type
of question
1. What are the phenomena/problems?
 Observation (e.g., qualitative research)
2. What is frequency of the problem? (FREQUENCY)
 Random (or consecutive) sample
3. Does this person have the problem? (DIAGNOSIS)
 Random (or consecutive) sample with Gold Standard
4. Who will get the problem? (PROGNOSIS)
 Follow-up of inception cohort
5. How can we alleviate the problem?
(INTERVENTION/THERAPY)
 Randomised controlled trial
Treating hyperkalemia
She refused to go to hospital
Resonium A, but it is around $100 (RPBS
but not PBS) which she could not afford.
My search had mentioned albuterol as a
treatment.
Step #4
Applying the results
in clinical practice
“Just in Time” learning
The EBM Alternative Approach
 Shift focus to current patient problems
(“just in time” education)
 Relevant to YOUR practice
 Memorable
 Up to date
 Learn to obtain best current answers
Dave Sackett
Advanced threshing
Read the abstract
Read the author list
Read references cited in several other
papers
Consider levels of evidence
(as far as you can from abstracts)
Step #5 Explain Evidence
Internal validity
Is the study credible?
Was it done welll?
Was it done right?
Do you believe the authors?
Is the study good enough to consider
making decisions based on its results?
Levels of evidence
Randomised controlled trials
Cohort studies
Case-control studies
Routine data hunting
Case series
Case reports
Allow for serendipity
Type and Strength of Evidence
Absolute truth or divine revelation
I
Systematic review of well designed RCTs
II Well designed RCT of appropriate size
III Nonrandomized trials: single group pre-post, cohort,
case control
IV Non-experimental studies from more than one site or
research group
V Opinions of respected authorities, not based on above
VI Someone once told me
Quality of evidence
Use Sackett’s guidelines for the various
different types of study
Gain experience
Quality assessment is quite subjective, no
matter how experienced you are
Allow for serendipity
Assessing an RCT
A r e th e r e s u l t s o f th i s s i n g l e p r e v e n t i v e o r th e r a p e u t i c
tr i a l v a li d ?
W a s th e a s s ig n m e n t o f p a ti e n t s t o tr e a t m e n t
r a n d o m i s e d , a n d w a s th e r a n d o m is a t i o n lis t
con c e aled ?
W e r e a ll p a ti e n t s w h o e n t e r e d th e tria l
a c c o u n t e d f o r a t it s c o n c lu s i o n ?
W e r e th e p a t i e n t s a n a ly s e d in th e g r o u p s t o
w h ic h th e y w e r e r a n d o m i s e d ?
W e r e p a ti e n t s a n d clin ic i a n s k e p t b lin d a s t o
w h ic h tr e a t m e n t w a s r e c e i v e d ?
A s id e fr o m th e e xp e r i m e n t a l tr e a t m e n t w e r e
th e t w o g r o u p s tr e a t e d e q u a lly ?
W e r e th e t w o g r o u p s si m il a r a t th e st a rt o f th e
tria l ?
External validity
Given that the study is credible, and in
some sense that it is good enough..
Is it of any use?
Can I apply the results at all?
Is it likely that my patients are like those
in the study?
Does it apply to me?
Well, does it apply to
My continent?
My setting?
My patients?
Women?
Children or elderly people?
Poor people?
The four B’s
Burden of illness (the patient's, towns, etc
risk of the event)
Barriers to treatment (including
economics, geography, etc)
Behaviours needed (yours and your
patient's) to adopt the treatment
Balance between expending efforts this
way or in some other way.
Step #6 Performance
evaluation
Validity
Sackett proposes that internal validity
should be left to experts (people like 柯)
External validity should be left to users
(people like 林)
Is it wrong…
What do you think?
Evidence based practice
Is it possible to do this?
Isn’t this just the latest fashion?
Isn’t it too difficult?
What about clinical freedom?
Aren’t we becoming overpaid clerks?
Why does it matter?
Is it possible?
Yes
Real clinicians are doing it now
It addresses a genuine clinical need
Clinicians need information
If asked
We need it twice a week
We get it from textbooks and journals
The Slippery Slope
knowledge
of current
best care
. ..
. . ........
...
r = -0.54
p<0.001
...
...
....
..
....
years since
graduation
Clinicians really need information
If shadowed
We need it up to 60 times a week (twice
per three patients) and it could affect up
eight decisions a day
We only get 30% of it
and that comes from passers-by
my textbooks are out of date
my journals are too disorganised
Our patients need it too
Patients die when doctors make it up as
they go along.
Proven for
Tuberculosis treatment
Testicular cancer treatment
Abdominal aortic aneurysms
Myocardial infarction
Why we get it wrong
Our information is out of date
Our textbooks are very out of date
Nobody can read enough journals to keep
up.
We are taught to remember in medical
school, not to think.
What can we do?
Accept that there is a problem
Take steps to fix it
Review of practice (Audit)
Review of clinical decisions (EBM)
Review of outcomes (Quality assurance)
Why are people afraid?
Appraisal is challenging
It’s easy to perceive it as a threat
In practice it often is
We are not used to thinking reflectively
about what we do. It’s not part of the
medical ethos.
Is EBP just a fad?
Nope
Is EBP going to turn us into
mindless automatons?
Not unless you are one already
Guidlines are what they say - GUIDES
Good practice includes careful and
reflective application of guidelines, and
other pieces of knowledge to the
individual patient
Medicine is an art and a science
What about clinical freedom
Freedom to do harm is not available
Freedom to do good is
Patients are unique
We must individualise care
We must care, as well as diagnose and cure
We must be responsible or else lose our
freedom
The Barriers to EBP
1. Attitude of question & inquiry
2. Know-how in finding, appraising, and
applying evidence
3. Information Resources on tap
4. Lack of Time
EBP in Teams
Question focused journal clubs
Structure:
Appraise & apply “homework” article
New questions? Discuss & assign
Plan and monitor changes
Are there barriers to the change?
Can we measure the change?
EBP for Teams: example
Initial “EBP lunch” questions on annual check
TRIGGER: Is blood monitoring better than urine
monitoring in NIDDM? – No; give patients option
Session 1: formulate questions
Should all diabetics be on aspirin? – Most; audit
Are aerobic or resistance exercises helpful for
diabetic control? – Both improve control; audit;
purchased 12 pedometers
(Subsequent sessions)
Who needs to see the podiatrist? – High risk
What is the best test for neuropathy? - Monofilament
How can we improve compliance?
When should oral medications be started?
Using evidence for prioritising
Q: Which diabetics need podiatry?
PLAN
Current wait time is 3 Months
About half workload is diabetics
Cohort study shows 2% ulcers/yr with 5 risk factors
Current ulcer
Past ulcer
Neuropathy
Deformity
Poor pulses
Abbot. Diab ed 2002: 377-84
Summary
Is there an information deluge?
Yes – 5,000 articles per day
Does CME help?
Maybe a little
Can EBM (patient-centred learning) help?
Yes, it uses the more effective methods of CME
What are the barriers?
Evidence resources, skills, inquiring attitude
What is evidence-based
practice?
Clinical Skills
Keeping
up to date
Clinical question
THE
PATIENT
Audit
Find the Evidence
Apply to Practice
Critical Appraisal
Current Format Emphasizes
Small group learning
On-the-fly reviews
Rapid analysis of medical literature/evidence
Single clinical question per month
Module approach
Treatment
Diagnosis
Harm
Assigned Resident Preparation
Choose a “real patient” scenario in
which a clinical question has arisen
Literature search performed
3 articles chosen
not distributed beforehand
Lead the discussion of an article
worksheet completed ahead of time
EBM - Journal Club
30 minute social time
Good food and beer help with attendance!
1.5 hours EBM exercise
Mini-Lesson
10-minute “mini-lesson”
Prepared & presented by faculty sponsor
Topic examples:
Hierarchy of evidence
NNT/NNH
RR/OR
2X2 tables
Case control, cohort studies
EBM – Journal Club
Clinical Scenario is presented
Clinical question is constructed (PICO)
PICO
EBM – Journal Club
Handout of Medline search provided –
brief discussion
Search Sample
EBM – Journal Club
Divide into 3 small groups
Led by EM resident
Everyone provided EBM worksheet
Each group discusses one of the articles
EBM – Journal Club
Given 5 minutes to review the article
“on the fly” philosophy teaches residents to
efficiently read/scan the medical literature
Seek out tables, figures
leader takes group through the worksheet
EBM – Journal Club
Entire group reconvenes
Spokesperson from each group
summarizes worksheet
Closing the Loop
Integrating the evidence with clinical
experience and patient preferences, values
Translating the evidence
Can I apply the results to my patient in my locale?
Will the evidence change my practice behavior?
How do we handle “imperfect” evidence?