Specific classification of elibrary resources says more about users preferences'

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MIE 2006, August 27th30th, MECC, Maastricht, The
Netherlands. UBIQUITY Technologies for better
health in aging societies.
Specific classification of elibrary resources
says more about users preferences.
Judas Robinson, Postgraduate Student, St.
Georges, University of London, Cranmer Terrace,
Tooting, London, SW17 0RE jsrobins_at_sgul.ac.uk
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Primary Care Electronic Library http//www.pcel.in
fo
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Digital Libraries Produced by the PCI Group at
St. Georges
DrsDesk (1998-present) de Lusignan S, Brown A.The
Doctors Desk linking PCGs to NHSnet.Health
Service Computing May/June 1999
27-9. http//drsdesk.sgul.ac.uk NeLH-PC
(2000-2003) Gray JA, de Lusignan S. National
electronic Library for Health (NeLH) BMJ
19993191476-9. Online access 2005
September. http//www.pcel.org.uk PCEL
(2003-present) Robinson J, de Lusignan S and
Kostkova P. The Primary Care Electronic Library
(PCEL) five years on open source evaluation of
usage. Informatics in Primary Care.
200513(4)271-280. http//www.pcel.info
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Medical Coding and Classification Systems
Library Classifications Exemplified by Medical
Subject Headings (MeSH). Used by the National
Library of Medicine for indexing articles from
4,800 of the world's leading biomedical journals
for the MEDLINE/PubMED database. 20 000 terms
organised in hierarchies. Clinical
Classifications In current use by UK General
Practitioner are READ codes. It is planned that
these will be superseded by the SNOMED CT
classification, which is to be used in the
electronic patient record in the UK. 700 000
terms arranged in hierarchies. Epidemiological
Classifications The International Classification
of Diseases (ICD), published by the World Health
Organisation (WHO) has become the international
standard diagnostic classification for all
general epidemiological and many health
management purposes. Different classifications
for different purposes
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MeSH NLM distribution

• MeSH is available to download in XML and ASCII
  format from the National Library of Medicine
  (NLM) http//www.nlm.nih.gov/mesh/filelist.html.
  We currently use 2005 MeSH obtained in ASCII
  format.
• There are 22 000 MeSH headings arranged into 42
  000 nodes in the MeSH tree or hierarchy.
• Each mesh heading has a unique identifier (UI), a
  string text label or MeSH heading (MH), and one
  or more MeSH tree numbers (MN) identifying a
  terms position in the MeSH hierarchy.
• There are 15 MeSH headings covering the breadth
  of the vocabulary at the base of tree structure.
  Each MeSH term falls into one or more of these 15
  headings.
• MeSH is polyhierarchical. Each term may be the
  parent of more specific terms and similarly each
  term may be the child of broader terms. A given
  term, identified by a fixed MH and UI, may occur
  at more than one point in the hierarchy, that is
  it may have more than one MN.

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Example of hierarchical MeSH tree structure
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Example entry from MeSH distribution
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MeSH representation in UMLS
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MeSH representation advantages and disadvantages
of UMLS

• Advantages
• Taxonomy remains part of an integrated whole, the
  Metathesaurus, linking definitions from various
  source vocabularies.
• All hierarchical relationships are represented in
  the MRHIER table of the Metathesaurus.
• Regular updates available from NLM.
• Disadvantages
• The MeSH headings (numbering 22 000) are stored
  in the MRCONSO table of the Metathesaurus
  containing 3 500 000 entries.
• The hierarchical relationships of MeSH (numbering
  42 000) are stored in the MRHIER table of the
  Metathesaurus containing 7 500 000 entries.
• Entry points to UMLS are still provided using the
  CODE column in MRCONSO.

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Log files
Log files are plain text records of requests to a
server. Each line contains all the details of a
single request file requested, date, IP number
of the client, referring address for the request,
number of bytes served, and the user agent of the
client. Example records from the log file for
PCEL are shown below
68.142.250.160 - - - 30/Jun/2005135552 0100
"GET /index.cfm? fuseactionhome.sectionid200.14
0 HTTP/1.0" 500 540 "-" "Mozilla/5.0 (compatible
Yahoo! Slurp http//help.yahoo.com/help/us/ysearc
h/slurp) 68.142.251.55 - - - 30/Jun/20051400
37 0100 "GET /index_card.cfm? id3 HTTP/1.0"
404 6353 "-" "Mozilla/5.0 (compatible Yahoo!
Slurp http//help.yahoo.com/help/us/ysearch/slurp
) 194.82.51.28 - - - 30/Jun/2005141121
0100 "GET /imgs/sgul.gif HTTP/1.0" 200 3943
"http//www.pcel.info/" "Mozilla/4.0 (compatible
MSIE 6.0 Windows NT 5.1)"
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Requests for Resources from PCEL for the Four
Month Period January to April 2005
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Mapping between resource IDs and MeSH terms
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MeSH tree top Chi squared results for observed
versus expected values (Jan 2005)
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MeSH heading Information Science Chi squared
results (January 2005)
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Results and Implications

• User preferences were identified by analysis of
  the specific key MeSH headings associated with a
  resource.
• These preferences were not demonstrated for
  generic key MeSH headings.
• This implies that specific rather than generic
  MeSH headings should be used to classify
  resources. This is the recommendation of the
  National Library of Medicine, this paper provides
  an evidence base for this decision.

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MIE 2006, August 27th30th, MECC, Maastricht, The
Netherlands. UBIQUITY Technologies for better
health in aging societies.
Specific classification of elibrary resources
says more about users preferences.
Primary Care Electronic Library
http//www.pcel.info/ Power Point Presentation
http//www.gpinformatics.org/meetings.htm
Judas Robinson, Postgraduate Student, St.
Georges, University of London, Cranmer Terrace,
Tooting, London, SW17 0RE jsrobins_at_sgul.ac.uk