literature search
DESCRIPTION
LecTRANSCRIPT
1
Searching for the Evidence
Clinicians Need for Information
• When asked
– they need it twice a week
• When observed
– they need it 60 times a week
Clinicians’ Need for Information
When shadowed:
• we need it up to 60 times per week
(twice per every three patients)
• affect eight decisions per day
• but we get only 30% of it
• and that comes from passers-by
– “my textbooks are out of date”
– “my journals too disorganized”
Medline Database
• National Library of Medicine
– Bethesda, Maryland
• Abstracts of 3,500 journals
• 70 countries
– Philippines not included
• More than 30,000 new articles added per month
• 9 million articles since 1966
Structure of Database
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
FIELDS RECORDS
DATABASE
The Medline Database
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
NAME: _________________
AGE: ______ SEX: ______
ADDRESS: ______________
TEL. NO. ________________
PATIENT
AU: ____________________
TI: _____________________
SO: ____________________
AB: ____________________
MEDLINE
FIELDS RECORDS
DATABASE
2
0
1
2
3
4
5
6
7
8
66 69 72 75 78 81 84 87 90 93 96Years
Millions of Articles
The Medline Database
NLM
Main frame access
The Medline Database
The Medline Database
• Information explosion
• 700 MB of information
• 400,000 abstract per disc
Literature Retrieval Method
• Randomized comparative study (Verhoeven et al, 2000)
• Three groups
– Index Medicus
– Gratefulmed
– Medline CD-ROM
• Results
– Index Medicus better than Medline CD-ROM
– Gratefulmed better than Medline CD-ROM
– Index Medicus same as Gratefulmed
Searching MEDLINE
The Boolean Logic
12 3
4 5
6 78
9 1011
1213
14
15 16
A B
C
A OR B
A AND B
A AND B AND C
(A AND B) OR C
A AND (B OR C)
A AND (B AND C)
12 3
4 5
6 78
9 1011
1213
14
15 16
TB RCTs
MENINGITIS
TB OR RCTs
TB AND RCTs
TB AND RCT AND MENINGITIS
Searching MEDLINE
The Boolean Logic
3
PubMed Home Page Develop a Search Strategy
• Identify the key concepts (should include the PIOM
discussed earlier)
• Determine alternative terms for these concepts (can be
facilitated with MESH term search)
• Refine your search (use limits like publication dates,
study subjects, study designs, patient age, etc)
Advanced Search Strategy Advanced Search Strategy
Advanced Search Strategy
An Exercise
A 35 year old male came to your clinic complaining
of dizziness and headache. His BP was 150/100 and is
currently taking nifedipine 10 mg three times a day. Despite
this dose his BP remained uncontrolled.
Search MEDLINE for the most relevant article to
answer the clinical dilemma.