HINTS on using literature databases

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HINTS on usingliterature databases

• Louis Volkers Gerdien de Jonge
• Medical Library - Erasmus MC
• info.mb_at_erasmusmc.nl
• phone 87785

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Introduction

1. Literature retrieval the procedure
2. Available databases
3. How to access fulltext articles
4. Hints on PubMed
5. Demonstration
6. Questions?

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Literature retrieval the procedure

• Problem definition
• What is the problem? What do you want to know?
• Put the question into words as a full sentence,
  the best one is a question that can be answered
  with 'yes' or 'no
• Which are the important items in the question?
• Generate synonyms and equivalencies
• Be aware of British / American differences in
  spellingtumour OR tumor haemoglobin OR
  hemoglobin
• What type of combinations? AND OR NOT
• Which database(s) to use?
• Perform searches, and find references
• Evaluate the results
• Eventually repeat previous steps
• Collect relevant articles, read and interprete
  those
• Did this answer your question?

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Available literature databases

• Primary literature (results of original research)
• articles in journals (printed, electronic)
• books, reports, etc.
• Secundary literature (derivations of primary
  literature)
• compilations, often with summaries (indexes)
• PubMed (Medline), PsycInfo, Web-of-Science,
  PiCarta(EMbase is not available at this moment
  it is too expensive for us, there is an extensive
  overlap with the free Medline)
• Scopus (test), Google Scholar, searchable sites
  of publishers (Elsevier SciDir)
• Reviews, systematic reviews, meta-analyses
• Cochrane Library (Database of Systematic Reviews)
• UpToDate (a kind of an e-book on internal
  medicine and pediatrics)

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How to access fulltext articles?

• Available in Erasmus MC
• a collection of about 700 printed journals (in
  the Medical Library)
• a connection to about 4000 electronic journals
  (on the internet)
• Which? See the Alphabetic List of All Journals on
  MB home
• Journal not available?Request a photocopy
  (online request form not for free)

• PubMed opens up for about 4500 journals
• start PubMed from MB home to see fulltext links
• change Display Abstract for clickable links to
  accessible fulltext

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Types of search strategies

• (Example PubMed)
• Free-text searchsearch words in all fields
• Subject searchsearch subjects with standardized
  keywords (MeSH)
• PubMed combines both searches, depending on
  search terms
• Limit searchrestrict to several attributes (f.e.
  age groups, type of research)
• Index searchsearch by selecting terms in
  alphabetic lists
• Combine searches AND OR NOT

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Combinations
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Types of search strategies

• (Example PubMed)
• Free-text searchsearch words in all fields
• Subject searchsearch subjects with standardized
  keywords (MeSH)
• PubMed combines both searches, depending on
  search terms
• Limit searchrestrict to several attributes (f.e.
  age groups, type of research)
• Index searchsearch by selecting terms in
  alphabetic lists
• Combine searches AND OR NOT

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Subject search in Medline standard keywords

• MeSH Medical Subject HeadingsGenotypeFollow-Up
  Studies
• additional subheadings(depends on type of
  keyword) Peptidyl-Dipeptidase A/geneticsCardiov
  ascular Diseases/mortality
• used as major topic or minor topic
• functional tree structure gt explosion of terms

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Subject search in Medline standard keywords

• MeSH Medical Subject HeadingsGenotypeFollow-Up
  Studies
• additional subheadings(depends on type of
  keyword) Peptidyl-Dipeptidase A/geneticsCardiov
  ascular Diseases/mortality
• used as major topic or minor topic
• functional tree structure gt explosion of terms

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Record in PubMed (Display Citation)
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Subject search in Medline standard keywords

• MeSH Medical Subject HeadingsGenotypeFollow-Up
  Studies
• additional subheadings(depends on type of
  keyword) Peptidyl-Dipeptidase A/geneticsCardiov
  ascular Diseases/mortality
• used as major topic or minor topic
• functional tree structure gt explosion of terms

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MeSH - tree
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Types of search strategies

• (Example PubMed)
• Free-text searchsearch words in all fields
• Subject searchsearch subjects with standardized
  keywords (MeSH)
• PubMed combines both searches, depending on
  search terms
• Limit searchrestrict to several attributes (f.e.
  age groups, type of research)
• Index searchsearch by selecting terms in
  alphabetic lists
• Combine searches AND OR NOT

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How to find search terms?

• just type your words (not the optimal way for a
  scientist)
• click MeSH Database gt type word gt see MeSH
  terms gt see MeSH tree gt select MeSH term or
  select subheadings gt add to search box gt perform
  search
• type the word(s) gt Go gt Details gt see
  Automatic Term Mapping(next slide)
• type the word(s) restricted to Title fieldf.e.
  genetti AND statistti gt Go gt change
  DisplaySummary into DisplayCitation gt see
  the records indicated by 'indexed for MEDLINE' gt
  usefull terms in the MeSH field?(demonstration)

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Automatic Term Mappingsearch terms are
automatically mapped to MeSH terms

• Conditions for searching
• do NOT search with word roots and a wildcard ()
• do NOT search "quoted phrase"
• do NOT search by indexes (except for MeSH index)
• do NOT search in special fields (f.e.
  title)(except ALL fields or MeSH field)

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Automatic Term Mappingsearch terms are
automatically mapped to MeSH terms

• Conditions for searching
• do NOT search with word roots and a wildcard ()
• do NOT search "quoted phrase"
• do NOT search by indexes (except for MeSH index)
• do NOT search in special fields (f.e.
  title)(except ALL fields or MeSH field)

• When term mapping succeeded, PubMed searches like
  this (click Details)
• subject in MeSH fields OR text word in all text
  fields
• f.e. search term red blood cell
  gterythrocytesMeSH Terms OR red blood
  cellText Word (n127877)
• f.e. search term red blood cell gtred blood
  cellAll Fields OR red blood cellsAll Fields
  (n34658)

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SDI What's new in Medline?automatical updates
via "My NCBI"

• In "My NCBI" you can
• save your searches
• automatic check for new citations by e-mail
• special filter selections

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SDI What's new in Medline?automatical updates
via "My NCBI"

• In "My NCBI" you can
• save your searches
• automatic check for new citations by e-mail
• special filter selections

• Actions
• First time register next time log in with
  username and password
• Configure display filters
• Save searches, and configure e-mail updates
• View "My NCBI" make updates manually

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Locations in the Medical Library (2nd floor
building Ee)
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Demonstration

• go to the home page of the Medical Library
• http//www.erasmusmc.nl/medbib
• http//www.erasmusmc.nl/bibliotheek
• via Erasmus MC Intranet click gt Bibliotheek
• via Erasmus MC Internet click gt Bibliotheek

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