Methods for searching the literature: why and how? · Methods for searching the literature: why and...
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Methods for searching the literature: why and how? Dr. Evi Nagler Ghent University Hospital
Transcript of Methods for searching the literature: why and how? · Methods for searching the literature: why and...
Methods for searching the
literature:
why and how?
Dr. Evi NaglerGhent University Hospital
Conflict of interest
No ties with industryNo interest in systems discussed
BUT
Professional ties with guideline organisation
N° Questions
Q every 2 to 3 patients
≈10 questions
every day!
Green ML et al. AJM 2000; 109: 218-233.
N° Questions
Ramsey PG et al. JAMA 1991; 266(8):1103-1107.
If it works, we're right
If he dies, it was something else
Experience = Knowledge?
40
44
48
52
56
60
64
5 7 9 11 13 15
Bo
ard
sco
res
Years since initial certification
Board exam results for 300 internists
Ramsey PG et al. JAMA 1991; 266(8):1103-1107.
Experience = Knowledge?
0
20
40
60
80
100
Knowledge Diagnosis Therapy
Studies (%)
Poorer
No relation
Better
Systematic Review59 studies
Choudry NK et al. Ann Intern Med 2005; 142(4): 260-273.
Experience = Knowledge?
0
20
40
60
80
100
Knowledge Diagnosis Therapy
Studies (%)
Poorer
No relation
Better
Systematic Review59 studies
Choudry NK et al. Ann Intern Med 2005; 142(4): 260-273.
N° Questions
Ramsey PG et al. JAMA 1991; 26(8):1103-1107.
10 questions?
maybe more
N° Answers?
In 4 /10 questions Time Inability to navigate available
data Forget the question...
Ely J et al. J Am Med Inform Assoc 2005; 12(2): 217-224.
Shariff SZ et al. J Nephrol 2011; 24(6): 723-732.
Difference between physicians? Trainee ≈ Specialists Nephrologists ≈ Other internists Academic hospitals ≈ Community hospitals
Where do we look?
Shariff SZ et al. J Nephrol 2011; 24(6): 723-732.
SearchPD and peritonitis
First 40 citations 2 minutes
Evidence pyramid
StudiesUnfiltered
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Evidence pyramid
Systematic Reviews
StudiesUnfiltered
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Systematic Review Methods
Question definition
Systematic search
Study selection
Data extraction
Critical appraisal
Data synthesis
≈ 6 months
Usefulness equation
𝑈𝑠𝑒𝑓𝑢𝑙𝑛𝑒𝑠𝑠 =𝑅𝑒𝑙𝑒𝑣𝑎𝑛𝑐𝑒 ∗ 𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦
𝑊𝑜𝑟𝑘
Shaughnessy AF et al. J Fam Pract 1994; 39: 489-499.
Little workHighly relevant Higly valid
Usefulness equation
𝑈𝑠𝑒𝑓𝑢𝑙𝑛𝑒𝑠𝑠 =𝑅𝑒𝑙𝑒𝑣𝑎𝑛𝑐𝑒 ∗ 𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦
𝑊𝑜𝑟𝑘
Shaughnessy AF et al. J Fam Pract 1994; 39: 489-499.
Little workHighly relevant Higly valid
Evidence pyramid
Studies
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Evidence pyramid
Studies
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Evidence pyramid
Summaries
Systematic Reviews
Studies
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Where do we look?
SearchPD and peritonitis
Where do we look?
SearchPD and peritonitis
15 seconds !
Where do we look?
SearchPD and peritonitis
Where do we look?
SearchPD and peritonitis
15 seconds !
Usefulness equation
𝑈𝑠𝑒𝑓𝑢𝑙𝑛𝑒𝑠𝑠 =𝑅𝑒𝑙𝑒𝑣𝑎𝑛𝑐𝑒 ∗ 𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦
𝑊𝑜𝑟𝑘
Shaughnessy AF et al. J Fam Pract 1994; 39: 489-499.
Little workHighly relevant Highly valid
Usefulness equation
𝑈𝑠𝑒𝑓𝑢𝑙𝑛𝑒𝑠𝑠 =𝑅𝑒𝑙𝑒𝑣𝑎𝑛𝑐𝑒 ∗ 𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦
𝑊𝑜𝑟𝑘
Shaughnessy AF et al. J Fam Pract 1994; 39: 489-499.
Little workHighly relevant Highly valid
Relevance - coverage
0
20
40
60
80
100
ACP Pier Clinical Evidence Dynamed UpToDate
Banzi 2010
Prorok 2011
Banzi R et al. J Med Int Res 2010; 12(3): e26.
Prorok JC et al. J Clin Epi 2012; 65: 1289-1295.
Relevance - coverage
0
20
40
60
80
100
ACP Pier Clinical Evidence Dynamed UpToDate
Banzi 2010
Prorok 2011
Banzi R et al. J Med Int Res 2010; 12(3): e26.
Prorok JC et al. J Clin Epi 2012; 65: 1289-1295.
No tool covers every question
Relevance - Timeliness
0 5 10 15 20 25
ACP Pier
Clinical Evidence
Dynamed
UpToDate
Time (months)
No tool is to the date
Prorok JC et al. J Clin Epi 2012; 65: 1289-1295
Usefulness equation
𝑈𝑠𝑒𝑓𝑢𝑙𝑛𝑒𝑠𝑠 =𝑅𝑒𝑙𝑒𝑣𝑎𝑛𝑐𝑒 ∗ 𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦
𝑊𝑜𝑟𝑘
Shaughnessy AF et al. J Fam Pract 1994; 39: 489-499.
Little workHighly relevant Highly valid
Usefulness equation
𝑈𝑠𝑒𝑓𝑢𝑙𝑛𝑒𝑠𝑠 =𝑅𝑒𝑙𝑒𝑣𝑎𝑛𝑐𝑒 ∗ 𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦
𝑊𝑜𝑟𝑘
Shaughnessy AF et al. J Fam Pract 1994; 39: 489-499.
Little workHighly relevant Highly valid
Validity
0
20
40
60
80
100
ACP Pier Clinical Evidence Dynamed UpToDate
Banzi 2010
Prorok 2011
Banzi R et al. J Med Int Res 2010; 12(3): e26.
Prorok JC et al. J Clin Epi 2012; 65: 1289-1295.
Validity
0
20
40
60
80
100
ACP Pier Clinical Evidence Dynamed UpToDate
Banzi 2010
Prorok 2011
Banzi R et al. J Med Int Res 2010; 12(3): e26.
Prorok JC et al. J Clin Epi 2012; 65: 1289-1295.
No tool has perfect validity
Evidence pyramid
Summaries
Systematic Reviews
Studies
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Less workLess detail
More workMore detail
Evidence pyramid
Summaries
Systematic Reviews
Studies
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Where do we look?
PD and peritonitis
15 seconds !
Evidence pyramid
Summaries
Systematic Reviews
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Randomised trials
Where do we look?
PD and peritonitis
10 minutes
Evidence pyramid
Summaries
Systematic Reviews
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Randomised trials Cohort studies Case-control studies Case-series Case reports
Where do we look?
Shariff SZ et al. J Nephrol 2011; 24(6): 723-732.
SearchPD and peritonitis
Hours
General advise
Adapted from Haynes RB. EBM 2001; 6: 36-38.
Criticims
Some questions I KNOW are not covered!
If you’re right you’ll lose 45 seconds
If you’re wrong you could spare yourself embarrasment
Criticims
Not detailed enough!
𝑈𝑠𝑒𝑓𝑢𝑙𝑛𝑒𝑠𝑠 =
𝑅𝑒𝑙𝑒𝑣𝑎𝑛𝑐𝑒 ∗ 𝑉𝑎𝑙𝑖𝑑𝑖𝑡𝑦
𝑊𝑜𝑟𝑘
Criticims
Dangerous if you ask me!!!
For > 50% of questions, we don’t look for an
answer, but we ALWAYS take a decision
Oh, and stupidity is always dangerous...
What to remember
Search strategically: top-to-bottom
Don’t be ashamed of using point-of-care tools
Information you can search, but no-one can do the thinking for you!
