Finding the Evidence

Pragmatic Information Retrieval in the of Context of Evidence-based Healthcare

Exeter

September 2010

Kate Boody

Reinhard Wentz

“It’s publish or perish – and he didn’t publish!”

Just One Definition of EBHC:

An approach to health care practice in which the clinician is aware of theevidence in support of his/herclinical practice, and the strength ofthat evidence

Postgraduate Medical Journal 1996;72:1

Preconditions for Successful EBHC

• Start with a focused, answerable question

• Select a high-yield database

• Formulate a simple search

Preconditions for Successful EBHC

• Start with a focused, answerable question

• Select a high-yield database

• Formulate a simple search

Unfocused (unanswerable) Questions

• Is health promotion a good thing?

• How to treat diabetes in pregnancy?

• Is physiotherapy useful?

• Why is Mrs. Gupta depressed?

Answerable question

How effective is a single dose

of dexamethasone in

outpatient croup?

Answerable question

Does the presence of a

Doula reduce caesarean

section rates?

Answerable question

How effective is aspirin in

preventing DVT in patients

following hip-replacement?

Answerable question

What is the predictive value of

PCR compared to routine

blood culture in the

treatment of neonatal sepsis?

Answerable question

How effective is

acupuncture in smoking

cessation programs?

Aspects of the ‘Answerable Question’

• Patient or Problem• Intervention or

exposure• Comparison

• Outcome

= PICO

Preconditions for Successful EBHC

• Start with a focused, answerable question

• Select a high-yield database

• Formulate a simple search

High-yield Databases Extracting · Evaluative · Synthesizing Databases

• PubMed (especially Clinical Queries Option)

• Cochrane Library

• Google Scholar

• NHS Evidence

• TRIP

• Quality Sites on the Web etc.

Preconditions for Successful EBHC

• Start with a focused, answerable question

• Select a high-yield database

• Formulate a simple search

Answerable question

How effective is a single dose

of dexamethasone in

outpatient croup?

Suggested Search Strategy

Think ‘Telegram’

?

Answerable question

How effective is a single dose

of dexamethasone in

outpatient croup?

Answerable question

How effective is a single dose

of dexamethasone in

outpatient croup?

Answerable question

How effective is a single dose

of dexamethasone in

outpatient croup?

Answerable question

How effective is a single dose

of dexamethasone in

outpatient croup?

The search-formulation ‘telegramme’ (here: on PubMed)

Answerable question

How effective is aspirin in

preventing DVT in patients

following hip-replacement?

Answerable question

How effective is aspirin in

preventing DVT in patients

following hip-replacement?

Answerable question

How effective is aspirin in

preventing DVT in patients

following hip-replacement?

Answerable question

How effective is aspirin in

preventing DVT in patients

following hip-replacement?

Archie Cochrane 1909-1988

Cochrane AL. Effectiveness and Efficiency. Random Reflections on Health Services. London: Nuffield Provincial Hospitals Trust, 1972

All effective treatment mustbe free!

A. Cochrane circa 1935

Archie Cochrane 1909-1988

All effective treatment mustbe free!

A. Cochrane circa 1935

Answerable question

How effective is

acupuncture in smoking

cessation programs?

To recap …

Preconditions for Successful EBHC

• Start with a focused, answerable question

• Select a high-yield database

• Formulate a simple search

And finally ...

Start with a subject to which you know the answer: calibrate your skills (why?)

The curtain closes, only questions remainBrecht: The good woman of Szechwan

The End

And finally, again ...

Start with a subject to which you know the answer: calibrate your skills (why?)

Calibrate your skills!How effective are stockings toprevent DVT in long-haul airline passengers?