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The level of evidence utilized to answer general practitioners’ questions Karen Davies
The level of evidence utilized to answer general practitioners’ questionsKaren Davies
Evidence Based Medicine
2 Karen Davies, 2010
Clinical Expertise
Patient Preferences
Research Evidence
Haynes et al., 1996
EBM - Levels of Evidence
3 Karen Davies, 2010
Meta analy
sisSystematic Revie
wsRandomized Controlled Clinical Trials
Cohort StudiesCase Control StudiesCase Series / Reports
Anecdotal
Level One
Level Two
Research Objectives• To determine the highest level of evidence
per question• To determine the number of questions not
answered due to a lack of evidence• To determine the number of times a guideline was used to answer a question
• To determine the type of websites used to answer questions
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EBM Levels Used in This Study
5 Karen Davies, 2010
(Meta analys
is)Systematic Revie
wsRandomized Controlled Clinical Trials
Cohort StudiesCase Control StudiesCase Series / Reports
Anecdotal
Guidelines
Websites
Level One
Level Two
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Methodology• Two national primary care answering
services - ATTRACT and NLH Primary Care Answering Service
• Clinical questions• Identified the type of evidence used to
answer the question• Data was collected for four months, from
1st March to 30th June 2008•
Highest Level of Evidence
• 11 of the 57 ATTRACT questions answered by level 1 or 2 in the evidence hierarchy – 19%
• 74 of 724 Primary Care Answering Service questions answered by level 1 / 2 evidence – 10%
• Average 11%
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Questions Not Answered
• 2 out of 57 ATTRACT questions – 3.5%
• 125 out of 724 NLH Primary Care Answering Service questions – 17%
• Average 16%
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Guidelines Used
• 24 of the 57 questions from ATTRACT - 42%
• 301 of the 724 questions from NLH Primary Care Answering Service – 42%
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Type of Websites
• 14 (18%) websites were used by ATTRACT and 116 (25%) by Primary Care Answering Service
• Not for Profit• NHS (National Health Service)• Average – 17%
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Evidence for the Questions
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Leve
l 1
Leve
l 2
Guideli
nes
Web
sites
Other
Not Ans
wered
0
10
20
30
40
50
NLHATTRACT
Questions and Their Evidence I• What evidence is there for the use of
light boxes in the treatment of SAD?• Are there any alternative /complimentary
therapies recommended for IBS?• Are there benefits from mindfulness
therapy?• What is the evidence for the use of statin
in secondary prevention in the over 80's?
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Questions and Their Evidence II• In a 36 year old, hysterectomy and not
eligible for HRT, how do we manage osteoporosis risk?
• What are the potential causes of foot numbness, spreading to both legs?
• Can a tens machine be used by a patient who is 20 weeks pregnant?
• Is there any evidence of an interaction between warfarin and litozin?
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Why Is This Research Useful?
• NLH Primary Care Answering Service closed
• Useful service• Guidelines may answer 40% of
questions• 10% of questions were answered using
level 1 or 2 evidence
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