Searching for Evidence

Evidence in Practice (MiC/PPD)

December 2014

Focus on “the literature”

• what is it?• finding it• using it

• in the context of EBM and asking answerable questions to find the “evidence”

Types of literature

• Published - widely available – books, journals, newspapers, web pages

• Semi-published - smaller circulation– a.k.a. grey literature– internal reports e.g. NHS departments, hospitals,

regions

• Unpublished– theses, correspondence, patient records

Types of resources

• Primary– case reports, clinical trials, original research

• Secondary

“distilled knowledge”– textbooks, reviews, systematic reviews

• Tertiary– finding aids – indexes/abstracts

• e.g. Medline, Cochrane Library, NICE Evidence

Finding answers

What are you looking for?• In an adult with cold-like symptoms does

treatment with antibiotics improve time to recovery?– Patient/problem– Intervention– Comparison intervention– Outcomes

PICO

• P - adult (middle-aged female) with cold-like symptoms

• I - treatment with antibiotics

• C - no treatment, other remedies

• O – faster recovery

Planning a search strategy

• key terms to search with• one concept per column

common cold treatment antibiotics

Combining terms

AND

common cold AND antibiotics

OR

amoxycillin OR penicillin

Boolean operators

Boolean operators

• use the Boolean operators to help you express your search logically

ANDcommon cold treatment antibiotics

AND

increases SPECIFICITY

Synonyms and spellings

• think about other terms which mean the same i.e. synonyms, or related terms– treatment, therapy

• remember alternative spellings e.g. US vs British– organisation/organization– behaviour/behavior– oestrogen/estrogen

Synonyms need OR

AND

OROR

common cold

treatment antibiotics

upper respiratory tract infection

therapy penicillin

AND

increases SENSITIVITY

Widening a search

Other options with keyword searching:

• use truncation to pick up plurals or other word endings – e.g. therap* = therapy, therapies

• use wildcards to pick up spelling variants– e.g. wom?n= woman, women

Where to search?

• What kind of information do you want?• Which finding aids/tertiary resources

cover this type of information? e.g.– Library Catalogue for books or Discover

for books, journal articles, theses, images, and more

– Databases e.g. Medline for journal articles– Cochrane Library for systematic reviews– NICE Evidence for UK guidelines, etc

Key resources for EBM• NICE Evidence Search (formerly NHS Evidence)• NICE Clinical Knowledge Summaries• Cochrane Library• TRIP database• Evidence-based Medicine Reviews (via Ovid)

– ACP Journal Club– Cochrane Database of Systematic Reviews– Database of Abstracts of Reviews of Effects

See Library’s subject information page for Medicine

Scenario

Mr Smith, 45, has recently been diagnosed with moderate depression. He thinks antidepressants will help as he can’t take time off work. Is this the best option?

In pairs create a PICO structure for this question and then identify your key search terms...

• P – 45yr old male with moderate depression

• I – antidepressant therapy• C – no treatment, psychological therapy• O – recovery, improved quality of life

moderate AND antidepressants depression

Moderate-to-severe depression — antidepressants are effective for treating people with moderate or severe depression. It is estimated that for people with moderate-to-severe depression: if no treatment is given, 20% will recover; if a placebo is given, 30% will respond; and if an antidepressant is given, 50% will respond [Anderson et al, 2008; Taylor et al, 2012b]. This means that it is necessary to treat three people with an antidepressant compared with 'true' no treatment for one additional person to respond (NNT 3), and that it is necessary to treat five people with an antidepressant compared with placebo for one additional person to respond (NNT 5).

Summary

• literature – types + primary, 2ndry• planning a search – PICO• combining searches (using Boolean operators)

• widening searches• selecting the right “finding aids”• key EBM resources

Help with using resources

• Have a look at the Library’s Subject Information page for Medicine

• Contact your Academic Liaison Librarian

Heather Robb (heather.robb@dur.ac.uk)

• Workshops in February – using Medline & Embase via Ovid