SEARCHING EMBASE Searching EMBASE - UKMi · 2015-05-09 · Session aims •To understand the...
Transcript of SEARCHING EMBASE Searching EMBASE - UKMi · 2015-05-09 · Session aims •To understand the...
Searching EMBASE
Joanne McEntee
Medicines Information Pharmacist North West Medicines Information Centre
SEARCHING EMBASE
National Training Course
Session aims
• To understand the differences between Medline
and Embase.
• To know that Medline records are included in
Embase and understand how this is done.
• To understand why you need Medline AND
Embase.
• To know how the EMTREE thesaurus is organised.
• To know how to search Embase.
• To practise searching Embase (and Medline).
Plan
• What is Embase? (see pre-course material)
• Medline vs. Embase (see pre-course material)
• Medline on Embase
• EMTREE thesaurus
• Search tools in NHS Evidence/OVID
• Worked examples
Medline on Embase
• Since Jan 2010, Medline records are included in
Embase.
• On all platforms including Ovid.
• Daily feed from Medline to Embase.
Medline on Embase (continued)
De-duplication process
• Medline covers 2,500 unique journals (and 3,000
common ones).
• If record already in Embase, Medline record not
added, but de-duplication not 100%.
• If same record subsequently added that is
indexed by Embase, the Medline-unique version is
replaced.
Medline on Embase (continued)
Indexing of records
• MESH terms are mapped to EMTREE terms –
abstracts are not re-keyworded.
• All records can be searched using EMTREE or
MESH terms.
Medline on Embase (continued)
Publication type index
• >50 publication types indexed in Medline vs.
8 in Embase.
• These mapped to Embase publication type
or EMTREE term
e.g. clinical trial is publication type in Medline and EMTREE term in Embase.
Medline on Embase (continued)
MESH sub-headings
• Medline sub-headings are mapped to EMTREE
sub-headings where possible.
• E.g. adverse effects > adverse drug reactions .
• There are 19 equivalent terms.
• 61 MeSH sub-headings mapped to EMTREE terms
• E.g. contraindication (SH) > drug contraindication (ET).
Medline on Embase (continued)
Checktags
12 Medline checktags:
• 8 map directly to EMTREE terms (animal, case report,
comparative study, male, female, human, in vitro,
pregnancy).
• 4 are ignored (not relevant).
Should you search only Embase?
As well as incorporating Medline……..
• Embase records have more keywords vs. Medline.
• Embase indexes abstracts from 800 conferences a year (since 2009).
• Embase indexes ‘articles in press’ from 1,500 journals.
• EMTREE twice as large as MeSH.
• EMTREE includes more drug names and more are added 3 times a year.
Why you still need Medline…..
• Indexing is subjective and the methods differ between Medline and Embase.
• More subheadings are available in Medline (for all subjects since 1966 vs. drugs and diseases only since 1988 in Embase), allowing a more precise search.
• Fields, limits and subject structures are different.
Searching EMBASE
• Controlled vocabulary = EMTREE
• Uses natural language
• US spellings rather than British
• INNs used where possible
• Acronyms & abbreviations can be used
• Tree Structure (15) – Hierarchy
• Indexing: Terms added/Drug names
NICE Evidence Search
• www.evidence.nhs.uk
• Click ‘Journals and databases’
• Click ‘Healthcare databases advanced search’
• Type in your Athens password
• Select Embase.
• Embase 1974 to date
• 2 options to search for terms:
• Thesaurus mapping
• Browse headings
NICE Evidence Search and Ovid software
Explode/Major descriptor
Select • finds all articles where the term is listed (alone or with
subheadings or if a major term).
Explode • Searches for the term and all the terms below below in the
tree structure.
• ‘exp’ is put before keyword in results.
Major descriptor (focus) • Only includes articles where the keyword (descriptor) is the
main focus of the article.
• ‘ ’ is put before keyword in results.
Subheadings
• Two types – drugs and diseases
• Fewer subheadings for diseases than Medline
• Many more subheading options for drugs than
Medline, e.g. diclofenac
• Can select more than one subheading
CAS numbers
• No need to use them in EMBASE.
• Most medicines have EMTREE terms – even
recently licensed ones.
• If a drug hasn’t got an EMTREE term assigned –
use free text.
Limits
• Limit searches in similar way to Medline.
• Differences compared with Medline.
Publication types
• Publication types have their own facet / tree
top of EMTREE terms that are searchable.
• Facet J: types of article or study.
• Build up your search and combine in the usual
way (using BOOLEAN) with other search terms.
Worked example 1
Workshop question 1
Are there any papers specifically about using
linezolid to treat MRSA?
Worked example 2
Workshop question 2
Are there any review articles about inhaler use
in children with asthma aged under 4?
Worked example 3
Workshop question 5
Is there any evidence that minocycline is more
effective than any of the other tetracyclines
licensed for treating acne (tetracycline,
lymecycline, oxytetracycline, doxycycline)?
Getting help
ANY QUESTIONS?