View
36
Download
0
Category
Preview:
DESCRIPTION
Evidence based medicine. By: Mohsen Dehghani MSc Student in Epidemiology Isfahan University of Medical Sciences. Trace back to the development of EBM. Evidence based medicine. تلفیق بهترین شواهد بدست آمده از تحقیق با مهارتهای کلینیکی و ارزشهای بیمار. David Sackett, et al. 2000 - PowerPoint PPT Presentation
Citation preview
Evidence based medicineEvidence based medicine
ByBy::
Mohsen DehghaniMohsen Dehghani
MSc Student in EpidemiologyMSc Student in Epidemiology
Isfahan University of Medical SciencesIsfahan University of Medical Sciences
11
Trace back to the development of Trace back to the development of EBMEBM
Evidence based medicineEvidence based medicine
تلفیق بهترین شواهد بدست آمده از تحقیق با •مهارتهای کلینیکی و ارزشهای بیمار.
• David Sackett,
et al. 2000
استفاده دقیق، روشن و عاقالنه از بهترین شواهد •موجود برای تصمیم گیری در مورد مراقبت از یکایک
بیماران.
Best EvidenceBest Evidence
Patient values
Clinical expertise
33
Evidence based medicineEvidence based medicine
• Evidene based practice (EBP)
؟ نیاز داریم EBPچرا به •
44
Evidence based medicineEvidence based medicine
• Archei cochrane,• British epidemiologist, 1972
نوشت:1979او در سال •مطمئنأ انتقادی بزرگ از حرفه ما این است که برنامه ”•
ای برای خالصه کردن منظم و منتقدانه همه کارآزماییهای بالینی مربوط به یک موضوع در رشته های تخصصی و فوق تخصصی مختلف و بازبینی مستمر آنها
نداریم.“
• Cochrane center• Cochrane collaboration• Cochrane library
55
استفاده از کورتیکوستروئیدها در زایمان استفاده از کورتیکوستروئیدها در زایمان زودرسزودرس
• RCT-1972
• 6RCT, 1972 – 89
• Systematic review, 1990
• conclusion
66
PushPush, , PullPull, , …ways to deal with …ways to deal with
too much informationtoo much information
Evidence-Based Information Resources
77
0
2000
4000
6000
8000
1966 1976 1986 1996
Number of articles on Hypertension cited in Medline by Year
Articles
Increasing KnowledgeIncreasing Knowledge
88
The stepsThe steps
1. answerable questions
2. Find the best evidence
3. Critically appraise that evidence for its validity and usefulness
4. Apply the results
5. Evaluate the performance
99
Acquire the best evidence
Appraise the evidence
Applyevidence to patient care
Assess your patient
Ask clinical questions
EBM MethodEBM Method
1010
Where Clinical Questions Arise FromWhere Clinical Questions Arise From::
• Clinical findings • Aetiology: • Differential diagnosis: • Diagnostic tests: • Prognosis: • Therapy: • Prevention:
1111
Question components : PICO
• What types of Participants?
• What types of Interventions?
• What types of Comparison?
• What types of Outcomes?
1212
The four elements of well built clinical The four elements of well built clinical
questions:questions: ((PICOPICO))
Patient
Or
problem
InterventionComparison intervention
outcome
Tips for building
Starting with your patient ask
“how would I describe a
group of patients similar
to mine”?
Ask: “Which main
intervention am I considering”?
Ask “What is the main
alternative to compare with
the intervention”?
Ask “What can I accomplish?”
or “What could this exposure
really affect ”?
exampleIn healthy 1 year old infants
Does giving combined MMR
vaccine
When compared to
not giving
Lead to increased
incidence of autism?
1313
Best EvidenceBest Evidence……
• Journal of evidence based medicine.
• Encyclopedia of clinical evidence
1414
The Evidence PyramidThe Evidence PyramidT
ime S
pen
t in Critical A
ppraisal
Valid
ity/Strength of Inference
1515
Finding the EvidenceFinding the Evidence
systematic reviewsystematic review
1616
Systematic review & Meta-analysesSystematic review & Meta-analyses
تاثیر دریافت مواد غذایی در طول •زایمان بر پیامد مادری زنان باردار:
RCT
ارتباط بین چاقی و سکته مغزی•
درمان با انسولین و خطر ابتال به •سرطان
1717
1818
Overall (I-squared = 83.1%, p = 0.000)
sullivan et al (2009)
iran (2009)
parsons et al. (2007)
tranmer et al1 (2005)
scheepers et al. (2004)
Study
scheepers et al. (2002)
ID
scrutton et al. (1999)
parsons et al. (2006)
kubli et al1 (2002)
0.19 (0.13, 0.25)
0.14 (0.06, 0.22)
-0.24 (-0.53, 0.05)
0.88 (0.60, 1.16)
0.13 (-0.09, 0.35)
0.27 (-0.01, 0.55)
0.32 (0.04, 0.59)
SMD (95% CI)
0.31 (-0.11, 0.73)
0.63 (0.33, 0.94)
-0.34 (-0.85, 0.17)
100.00
63.16
4.66
5.07
8.54
5.22
%
5.18
Weight
2.27
4.35
1.54
0.19 (0.13, 0.25)
0.14 (0.06, 0.22)
-0.24 (-0.53, 0.05)
0.88 (0.60, 1.16)
0.13 (-0.09, 0.35)
0.27 (-0.01, 0.55)
0.32 (0.04, 0.59)
SMD (95% CI)
0.31 (-0.11, 0.73)
0.63 (0.33, 0.94)
-0.34 (-0.85, 0.17)
100.00
63.16
4.66
5.07
8.54
5.22
%
5.18
Weight
2.27
4.35
1.54
0-1.16 0 1.16
PubMed Clinical QueriesPubMed Clinical Queries
1919
PubMed Clinical QueriesPubMed Clinical Queries
2020
PubMed – Key FeaturesPubMed – Key Features
• Clinical Queries– Clinical study by category– Find systematic reviews
• MeSH Database– Synonyms (keywords) to use for your searches– Tutorials
• Comprehensive Limits Option
• “My NCBI” Alert, Storage and Retrieval Option
2121
2222
The Cochrane CollaborationThe Cochrane Collaboration
Preparing, maintaining and disseminatingsystematic reviews of the effects of health care
2323
Cochrane LibraryCochrane Library
• International collaboration• Produces systematic reviews and meta-
analyses of individual studies• DARE• Registry for RCT• Updated regularly• Abstracts are free• http://www.cochrane.org
2424
The Cochrane Library Total Records at The Cochrane Library Total Records at December 2010December 2010
DatabaseTotal Records
The Cochrane Database of Systematic Reviews (Cochrane Reviews) 6447
Database of Abstracts of Reviews of Effects (DARE)13521
The Cochrane Central Register of Controlled Trials (CENTRAL) 635,167
The Cochrane Methodology Register (Methodology Register)13,721
Health Technology Assessment Database (HTA)8908
NHS Economic Evaluation Database (NHS EED)28,991
About The Cochrane Collaboration and the Cochrane Collaborative Review Groups (About)80 2525
33.. Critically appraise that evidence Critically appraise that evidence for its validity and usefulnessfor its validity and usefulness
•1 -pico مطالعه چیست و آیا کامأل مشابه picoشماست؟
- مطالعه چقدر خوب انجام شده است؟2•
- نتایج چه معنی می دهند؟3•
2626
What is critical appraisal?What is critical appraisal?
• Critical appraisal is the assessment of evidence by systematically reviewing its relevance, validity and results to specific situations.
Chambers, R. (1998).
2727
Three questionsThree questions
• Valid?Is the methodology appropriate to answer the question.
Is it carried out in a sound way, eliminating bias and confounding?
• Reliable?Are the results real or because of chance?
• Applicable?Will the results help locally?
2828
2929
Dealing with chance errorDealing with chance error
• During design of study– Sample size– Power
• During analysis (Statistical measures of chance)– Test of statistical significance (P value)– Confidence intervals
3030
95% Confidence Interval 95% Confidence Interval (95% CI)(95% CI)
• 20 out of 100 participants: 20%
95% CI: 12 to 28• 80 out of 400 participants: 20%
95% CI: 16 to 24• 2000 out of 10000 participants: 20%
95% CI: 19.2 to 20.8
3131
3232
Quality assessment toolsQuality assessment tools
• Checklist : the components are evaluated separately and do not have numerical scores attached to them
• Scale: each item is scored numerically and an overall quality score is generated.
44 . .Apply the resultsApply the results
آیا تست یا درمان مورد نظر در بیماران مرکز طبابت من •قابل انجام است؟
آیا بیماران من متفاوت از افرادموجود در مطالعه است که •منجر به عدم کاربرد نتایج میشود؟
آیا روش دیگری در دسترس است؟•
آیا فواید بالقوه درمان بیش از زیانهای بالقوه آن •برای بیمار من است؟
بیمار من در این مورد چگونه فکر میکند؟•
3333
ThinkThink
اگر دانشجوییم وظیفه ما جستجوی علم و رعایت ادب و احترام استاد و ...
وظیفه ما این است که عمل به وظیفه کنیم
”Leonardo Davinchi“
3434
ReferencesReferences
• Paul glasziou, Chris Del Mar. Evidence-Based Practice workbook. University of Oxford; 2008
• Sackett DL, et al. Evidence Based Medicine: How to practice and teach EBM. Edinburge; 2000
• Glasziou P. Evidence based case report: Twenty year cough in a non-smoker. British Medical Journal 2006.
• http://www.cvidene-evidence-based medicine.com• http://www. Cochrane.org• Bero L, Rennie D. The Cochrane Collaboration. JAMA
2007 ;274:1935–8. • http://www.CONSORT-sratement.org/revisedstatement.htm.Vol.9 N
o.1, March 2007
3535
Recommended