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Step Two Finding the best evidence 1. Walk through one 2. Do own searches
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Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Mar 31, 2015

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Warren Sartell
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Page 1: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Step TwoFinding the best evidence

1. Walk through one2. Do own searches

Page 2: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Learning through play Try all “buttons” Make lots of

“mistakes” Have fun

Page 3: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

EBM and Systematic Review

EBM (quick & dirty) Steps

Answerable Question Search Appraise

Apply

Time: 90 seconds < 20 articles This patient survives!

Systematic Review Steps

Answerable Question Search ++++ Appraise x 2 Synthesize Apply

Time: 6 months < 2,000 articles This patient is dead

Find a systematic review!!

Page 4: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Start up Start Explorer and enter

www.pubmed.gov Put on CAPS lock

So that AND and OR are in CAPITALS Start 2nd Explorer window, enter

www.tripdatabase.com

Page 5: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Using the question to guide searching

Scenario - You are interested in checking the hearing of elderly patients, and have heard that the ‘whispered voice test’ is good.

Question Population Indicator (intervention, test, etc) Comparator Outcome

Page 6: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Using the question to guide searching

Scenario - You are interested in checking the hearing of elderly patients, and have heard that the ‘whispered voice test’ is good.

Question Population – in elderly patients does Indicator – a ‘poor’ whispered voice test Comparator – a ‘normal’ whispered voice test Outcome – predict abnormal audiogram

1. Underline the key terms2. Number the order of importance from 1-43. Think of alternate spellings, synonyms, &

truncations

Page 7: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Using the question to guide searching

Scenario - You are interested in checking the hearing of elderly patients, and have heard that the ‘whispered voice test’ is good.

Question Population – in elderly patients does Indicator – a ‘poor’ whispered voice test Comparator – a ‘normal’ whispered voice test Outcome – predict poor hearing (audiogram)

1. Underline the (root of the) key terms2. Number the order of importance from 1-43. Think of alternate spellings, synonyms, &

truncations

1

2

3

Page 8: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

* Means any other letters

AND means both terms required

Check the question type Check the

emphasis

Page 9: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Stepwise searching Search with #1 PICO item

Whisper* Then go to “Clinical Queries”: diagnosis

Whisper* (again) Add #2 PICO item

whisper AND (hear* OR audiogram)

Page 10: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Combining terms with Boolean operators – AND

chitosanweight

weight AND chitosan - has both terms

IN CAPITALS

Page 11: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Combining terms with Boolean operators – OR

chitosanweight

weight OR chitosan - has either term

Page 12: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Your tasks Search for the best single article

(systematic review or trial) for Your question from notes Your own question(s)

When you are finished Print just the abstract for each Write your search strategy on the

page

Page 13: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.
Page 14: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Boo-le-ans* AND = both terms OR = either term NOT = not this term (ADJacent, NEAR, … = AND +

close)

* George Boole (a man) is claimed to have invented “logic”

Page 15: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Where to the brackets go? If you want

cheese AND fruit

Which do you ask for? cheese AND (apple OR pear OR melon) (cheese AND apple) OR pear OR melon

What does PubMed do with if AND and OR? Cheese AND apple OR pear (Look at DETAILS tab)

Page 16: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

General structure of search

(Population OR synonym 1 OR …) AND (Intervention OR synonym 1 OR …) AND (Comparator OR synonym 1 OR …) AND (Outcome OR synonym 1 OR …) AND

FILTER (for best study type)

Page 17: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.
Page 18: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

MedlineEmbase

Cochrane Trials Registry

Comparing Databases

Medline = Pubmed, Webspirs, OVID, …

Page 19: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Search Cascade

Page 20: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Shortcuts Meta-search engines

www.tripdatabase.com Sumsearch Nelh

Page 21: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.
Page 22: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Other tips: Search on Title only

Eg [ti](Others are [au] - author; [so], [yr], …)

‘Related Articles’ button(PubMed)

previously identified study (PubMed)Look for the MeSH termsMeSH browser

Page 23: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.
Page 24: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Before you finish!

Print single most relevant abstract for each question – for both ‘set’ questions and your own questions

Page 25: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.
Page 26: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

More Tips on Effective Searching

Decide the TYPE of question (Rx, Dx, Px, …)

Chose the right database for the type of question, e.g., Intervention: Cochrane Library, PubMed, … Diagnostic: Common Diagnostic Strategies (in

BE), or PubMed: Clinical Queries Prognosis, Etiology: PubMed: Clinical Queries

Page 27: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Hearing problems in childhood Scenario - An immunisation and screening

booklet asks parents whether they think their child has any problems with hearing. While on a committee reviewing these questions, you wonder about the usefulness of this.

Question Population Indicator (intervention, test, etc) Comparator Outcome

Question Type - Rx, Dx, Px, … Database

Page 28: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Hearing problems in childhood Scenario - An immunisation and screening booklet

asks parents whether they think their child has any problems with hearing. While on a committee reviewing these questions, you wonder about the usefulness of this.

Question Population – In well children Indicator - does parental report of concern Comparator - nil Outcome – predict true hearing problems?

Question Type - Rx, Dx, Px, … - Diagnostic Accuracy Database – PubMed: Clinical Queries - diagnosis

Page 29: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Using the question to guide searching Question

Population – (child OR children) AND Indicator – (parent OR parental) AND Comparator - nil Outcome – (hearing)

Question Type Dx – Diagnostic Accuracy

Database – PubMed: Clinical Queries

Page 30: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Using truncation to save on ORs – the * Question

Population – (child*) AND Indicator – (parent*) AND Comparator - nil Outcome – (hearing) AND

Question Type Dx – Diagnostic Accuracy

Database – PubMed: Clinical Queries

Page 31: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

‘Wildcards’ malig* means

malignancymalignantmalign

but notmalunionmalalignedetc

Page 32: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Special tricks

Page 33: Step Two Finding the best evidence 1. Walk through one 2. Do own searches.

Write a “search” to get the green & red areas only