Evidence-based Practice
Resources for HINARI Users
(Module 7.2)
Evidence-based Practice Resources
for HINARI Users
Instructions - This part of the:
course is a PowerPoint demonstration
intended to introduce you to Evidence-based
Practice and related HINARI resources.
module is off-line and is intended as an
information resource for reference use.
Table of Contents – Part A
• Evidence-based Medicine (EBM)
– Definition
– What, why and how of EBM
– 5 step EBM process – ask, access,
appraise, apply
and access
– Limitations of EBM
Table of Contents – Part B
• HINARI Resources
– Clinical Evidence
– Cochrane Library
– EBM Guidelines
– BMJ Practice
– Essential Evidence Plus
– HINARI EBM Journals
Table of Contents – Part C
• Other (Internet) Resources:
– PubMed’s Clinical Queries and ‘Type of Article’ Limits
– Clinical Practice Guidelines – definition & examples
– Cochrane Library ‘Abstracts’
– PubMed Health – clinical effective research
– Trip Database
– Evidence Updates - BMJ and McMaster University
– Knowledge Translation Learning Modules – Canadian
Institutes of Health Research
– Essential Health Links gateway – annotated links
– Other useful websites
Evidence-based Practice (EBP) Definition
"Evidence-Based Practice requires that
decisions about health care are based on
the best available, current, valid and
relevant evidence. These decisions should
be made by those receiving care, informed
by the tacit and explicit knowledge of
those providing care, within the context of
available resources."
Sicily statement on evidence-based practice. BMC
Medical Education, 2005 Jan 5;5(1):1
What is EBP?
• The integration of best
evidence* from
current research,
patient preferences
and values, and clinical
expertise to clinical
questions (Sackett,
2000) in a timely
fashion.
Best Evidence
EBP
Patient
Values/Local
Conditions
Clinical
Expertise
*Best available evidence is: consistent research evidence with
high quality and quantity
Why EBP?
• To improve care
– To bridge the gap between research & practice
– “Kill as few patients as possible” (O. London)
– A new treatment might have fewer side effects.
– A new treatment could be cheaper or less invasive
– A new treatment may be necessary in case people
develop resistance to existing therapies, etc.
• To keep knowledge and skills current (continuing
education)
• To save time to find the best information
How does EBP help?
A patient comes to a clinic with a fresh dog bite. It looks
clean and the nurse and patient wonder if prophylactic
antibiotics are necessary. The nurse searches PubMed and
found a meta analysis indicating that the average infection
rate for dog bites was 14% and that antibiotics halved this risk
to 7%.
• For every 100 people with dog bites, treatment with antibiotics will
save 7 from infection
• Treating 14 (NNT) people with dog bites will prevent 1 infection
• You explain these numbers to the patient along with possible
consequences and patient decides not to take antibiotics.
On a follow up visit you find out that he did not get infected.
Glasziou P, Del Mar C, Salisbury J. EBP Workbook, 2nd. ed. BMJ Books, 2007.
What are some Barriers for EBP?
•
•
•
•
•
•
Overuse, underuse, misuse of evidence
Time, effort, & skill needed
Access to evidence
Intimidation by senior clinicians
Environment not supportive of EBP
Poor decision making
The 5 Step EBP Process
1.
ASK: Formulate an
answerable clinical question
2.
ACCESS: Track down the best
Evidence
3.
APPRAISE: Appraise the
evidence for its validity and
usefulness
4.
APPLY: Integrate the results
with your clinical expertise
and your patient values/local
conditions
5.
ASSESS: Evaluate the
effectiveness of the process
Ask
Assess
Access
Apply
Appraise
Step 1: ASK
a focused (answerable) clinical question
Ask
• Background questions (What do I know about this?)
• Foreground (Clinical) Questions
P = Patient, population or problem (Who are the patients or
populations? What is the disease?)
I = Intervention (What do you want to do with this patient
(e.g. treat, diagnose, observe)?
C = Comparison intervention (What is the alternative to the
intervention (e.g. placebo, different drug, nothing?)
O = Outcome (What are the relevant outcomes (e.g.
morbidity, mortality, death, complications)?
Why should I use PICO?
•
•
•
To help define problem in clarify it in your own mind
To prepare for searching
To ask patient centered questions. Treatment of
Pneumococcal Pneumonia SHOULD be different for
– Terminal Cancer Patient
– Elderly, Severely Demented Patient
– Young, mother of 2 children
• Developing the question requires:
– Some background knowledge of the condition
– Understanding of the patient and what are the outcomes
and beliefs that matter to this patient
• Death? Disability? Quality of life? Cost? Improvement
of symptoms?
Example: Intervention Questions
• Identify background questions, create a PICO
and a focused clinical question for this case:
54 year old male patient was diagnosed with
intermediate grade prostate cancer and wants
to know whether to get a radical
prostatectomy or radiation treatment. He is
concerned about death from prostate cancer
and also risks of impotence and incontinence.
Formulate the Clinical Question
• PICO
P - 54 year old male with intermediate grade prostate cancer
I - radical prostatectomy
C- radiation treatment
O- reduce risk of mortality, impotence, and incontinence
• Focused clinical question
In 54 year old male patients with intermediate grade prostate
cancer is radical prostatectomy more effective compared to
radiation treatment in reducing the risk of mortality,
impotence, and incontinence?
EBP Step 1a:
Classify the type of the question
• What is the treatment?
Question of INTERVENTION/PREVENTION
• What causes the problem?
Question of ETIOLOGY, RISK
• Does this person have the problem?
Question of DIAGNOSIS
• Who (and how likely) will get the problem?
Question of PROGNOSIS
Etiology and Risk Questions
What causes a disease or health condition?
• The reverse of intervention questions-they deal with
harmful outcomes of an activity or exposure (public
health issues)
• Develop a clinical question for the case:
S. is a smoker and just found out that she is 3
months pregnant. She quit smoking immediately. But
she is worried if her developing baby was harmed
and if the baby is at risk for having developmental
problems. She is asking you if smoking during the
first trimester can harm her baby?
Etiology or Risk Questions
• P-babies of mothers who smoke
I-smoking in first trimester
C-nothing
O-increase risk of developmental problems
• Question: Are babies of mothers who smoke
during their first trimester at an increased risk
of developmental disabilities?
Diagnosis Questions
• These questions are concerned with how accurate a
diagnostic test is in various groups and in comparison
to other tests or usually to a “gold standard test”.
As part of your clinic assessment of elderly patients,
there is a hearing check. You think that a simple
whispered voice test is very accurate compared to
other methods. You want to do a literature search.
What is your question? (1)
Glasziou P, Del Mar C, Salisbury J. EBP Workbook, 2nd. ed. BMJ Books, 2007.
Example
• P-elderly people
I-whispered voice test
C-no test (or other tests)
O-accurate diagnosis of hearing problems
• Question: In elderly people, does the
whispered voice compared to other tests give
an accurate diagnosis of hearing problems?
Glasziou P, Del Mar C, Salisbury J. EBP Workbook, 2nd. ed. BMJ Books, 2007.
Templates for EBP Questions
• For a therapy: In _______(P), what is the effect of _______(I) on
______(O) compared with _______(C)?
• For etiology: Are ____ (P) who have _______ (I) at ___
(Increased/decreased) risk for/of_______ (O) compared with ______ (P)
with/without ______ (C)?
• Diagnosis or diagnostic test: Are (is) _________ (I) more accurate in
diagnosing ________ (P) compared with ______ (C) for _______ (O)?
• Prevention: For ________ (P) does the use of ______ (I) reduce the future
risk of ________ (O) compared with _________ (C)?
• Prognosis: Does __________ (I) influence ________ (O) in patients who
have _______ (P)?
Melnyk B. & Fineout-Overholt E. (2005). Evidence-based practice in nursing & healthcare. New York: Lippincott
Williams & Wilkins.
EBP Step1b:
Decide on the best type of study for question
For each type of question there is a hierarchy of evidence
Therapy/Prevention
RCT>cohort > case control > case series
What should I do about this
problem?
Diagnosis
Does this person have the
problem?
Etiology/Harm
cross-sectional study with blind comparison
to a gold standard
RCT > cohort > case control > case series
What causes the problem?
Prognosis/Prediction
Who will get the problem?
RCT >cohort study > case control > case
series
Frequency and Rate
cohort study > cross-sectional study
How common is the problem?
NOTE: A well designed systematic review of RCTS (randomized
controlled trials) is best as it is least biased therefore more valid.
Hierarchy of Study Designs for Intervention
Least
• Randomized Controlled Trial
Experimental
• Cohort Studies
Observational
• Case-Controlled Studies
Observational
• Case reports/Clinical Observations
Observational
Bias
Most
Bias
To recognize the type of study ask the questions:
1. Is intervention randomly assigned? Yes-RCT; No-Observational study
2. When were the outcomes determined?
• After the exposure-cohort study (prospective study)
• During the exposure-cross-sectional study
• Before the exposure-case-control study (retrospective study based on recall)
EBP Step 2: ACCESS
Track Down the Best Evidence
Access
1. Start “hunting” from the best resource: Match your question
to the best medical information resource for this question.
•
Well designed Systematic Reviews¹ can be a great place
to start they contain commentary about validity
¹A systematic review involves the application of scientific
strategies, in ways that limit bias, to the assembly, critical
appraisal, and synthesis of all relevant studies that
address a specific clinical question.
Cook DJ, Mulrow CD, Haynes RB. Annals of Internal
Medicine March 1, 1997; 126 (5) 376.
Track Down
Hierarchy of Evidence- Access evidence at
the level that will give you the best evidence
Filtered & Critically Appraised
Expert Opinion and Not Filtered
Background info.
Most clinically relevant (at the top) Least clinically relevant (at the bottom)
Why not get info only from
textbooks and review articles?
• Texts and review articles?
– Dated – perhaps by several years
– Often biased
• Author chooses article that he/she agrees with (or has
written)
• Author chooses articles of his/her friends
• Author does not identify all the relevant literature
• Review’s methods are not explained
• These resources help with background knowledge
(learn about disease) not foreground (answer the
specific clinical question for this patient)
Why not get info only from
guidelines?
• They can assure standards of care but:
– Can be biased
– May not always be developed by experienced
experts
– Are not always evidence-based
– Can work for most patients but not for all
– Can work in some circumstances but not in all
– Can be dated
– There may not be guidelines for everything
Filtered and Critically Appraised
Evidence-Based Resources
• The Cochrane Library by The Cochrane Collaboration
via Wiley
– Independent non-for-profit international collaboration
– Reviews are among the studies of highest scientific evidence
– Minimum Bias: Evidence is included/excluded on the basis of
explicit quality criteria
– Reviews involve exhaustive searches for all RCT, both
published and unpublished, on a particular topic
– Abstracts searchable for free on the Internet; complete
database is available via HINARI for most countries
– 1995-
Benefits for using not-evaluated databases
for EBM research (PubMed, Cinahl)
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•
•
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Create comprehensive search strategies
Conduct systematic reviews of the literature
Conduct synonym searching utilizing thesauri
Set up and distribute alerts relating to evidencebased medicine
• Limit to specific populations & publication types
• Utilize EBM built-in filters (search strategies)
EBP Step 3: Appraise:
Appraise
Determine if the results are valid and useful
• Appraisal principles (primary and secondary research)
– What is the PICO of the study? Does it match my
question?
– How well was the study done? Is it biased?
– What do the results mean? Are they real and
relevant?
• More: University of Oxford’s Center of EBM:
http://www.cebm.net/index.aspx?o=1157
• Tools for evaluating studies can be found in the
Evaluating the Evidence section in the EBM tutorial at:
http://www.hsl.unc.edu/Services/Tutorials/ebm/welcome.htm
EBP Step 4: APPLY:
Integrate the results with your clinical
expertise and your patient values
Apply
• Question to ask:
– Is the intervention feasible in my settings?
– What alternatives are available?
– Is my patient so different then those in the study that the
results cannot apply ?
– Will the potential benefits outweigh the potential harms of
treatment ?
– What does my patient think? What are his cultural beliefs?
– Individual decision making/group decision making/choice
– Explaining risks and benefits to patients:
https://docs.google.com/View?id=d7k3gkg_679hnvn54c8
• Visual Rx: http://www.nntonline.net/visualrx/
EBP Step 5: ASSESS
Assess
Evaluate the effectiveness of the process.
How am I doing?
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Am I asking questions?
Am I writing down my information needs?
What is my success rate in the EBM steps?
How is my searching going? Am I becoming more
efficient?
• Am I periodically syncing (checking) my skills and
knowledge with new developments?
• Teach others EBP skills
• Keep a record of your questions
Limitations of EBP
• Limited scope of evidence-it will never be
complete
• The quality of research available
• Keeping it patient centered, cost effective
• Evidence from Randomized Controlled Trials
for real life patients
• Communicating uncertainties
• Decision making