1. Resources of scientific knowledge:
the weight of where to search
Joost Daams, MA
Medical Information Specialist
AMC medical library
1 October 2012

2. Introduction
The weight…
… of WHERE to search:
• Internet as resource of medical information
• Journals & articles
• Books & point of care tools
• Catalogs & digital library
• Bibliographic databases
• Guidelines & other resources of evidence

3. The weight of WHERE to search …
(…HOW to search is a different chapter ☺)
Lack of face validity:
the curious case of “meat bastards”
• Integrity
• transparency
• reproducibillity (validity)
… and evidence

4. Internet as resource of medical information (1)
How physicians get information to diagnose and treat patients
Derived from:
http://www.wolterskluwerhealth.com/News/Documents/White%20Papers/Wolters%20Kluwer%20Health%20Survey%20Executive%2
0Summary-Media.pdf, last consulted: 29th September 2012

5. Internet as resource of medical information (2)
What about:
• integrity
• transparency
• reproducibillity (validity)?
?? ??? ?
What about:
• content
• relevance ranking
• … and evidence?

6. Journals & articles (1)
The quality of a journal (≈ article) can be assessed by quality indicators:
1. Established reputation
e.g. Radiology is considered to be the top journal among radiologists, regardless of other quality inidcators
2. “Scientometrics”
e.g. Journal Impact Factor (JIF), Hirsch-Index, Web “ Sitations”
3. Peer-review (y/n)
4. ICMJE compliancy (y/n)
e.g. ethical considerations in the conduct and reporting of research, guidelines for the publication process as well
as the editorial process

7. Journals & articles (2)
More on the Journal Impact Factor (JIF)
JIF2011 = A/B
• What it is & application A = the number of times articles published in 2009 and
2010 were cited by indexed journals during 2011.
B = the total number of "citable items" published by that
journal in 2009 and 2010. ("Citable items" are usually
• Critique articles, reviews, proceedings, or notes; not editorials or
Temporality bias Letters-to-the-Editor.)
Geographical/language bias
Topicality bias
Incentive for self-citations
Range of provided subject topics
Assignment of journals to topics
Poor adaptation of web downloads / web citations
Non-transparent journal inclusion criteria by Thomson Reuters
Monolithic organisation
Strengths
“ Impact factor is not a perfect tool to measure the quality of articles but there is nothing better and it has the
advantage of already being in existence and is, therefore, a good technique for scientific evaluation.
(…) The use of impact factor as a measure of quality is widespread because it fits well with the opinion we have
in each field of the best journals in our speciality.”
(Hoeffel C. Journal Impact factors. Allergy. 1998;53;1225)

8. Journals & articles (3)
More on the International Committee of Medical Journal Editors (ICMJE)
• What it is & application
• Important (major?) achievement
“The ICMJE member journals will require, as a condition of consideration for publication in their journals,
registration in a public trials registry”
• … however publication bias is poorly addressed
“Editors should seriously consider for publication any carefully done study of an important question, relevant to their
readers, whether the results for the primary of any additional outcome are statistically significant.”

9. Journals & articles (4)
Open Access (OA) : a (would-be) idealists’ dream?
• What it is & application
Golden road or green road?
exposure
• What it’s not
A priori free access (from the authors’ point of view)
Already out there for all disciplines
A priori (not) peer-reviewed
Always protective of author rights
• Does OA influence JIF?
Further research is needed: only 1 study indicated increased downloads without a necessary influence on clinical
practice, but:
•` Researchers in the sciences do not see access to the scientific literature as an especially important problem
• Authors consider factors such as journal reputation and the absence of publication fees when deciding where to
submit their work. In contrast, free access is not a significant factor in their submission decissions.
(The impact of free access to the scientific literature: a review of recent research, Davis, Philip M. and Walters,
William H. Journal of the Medical Library Association. 2011;99(3);208)

10. Books & ‘point of care tools’
Making a “case” for books
Can exposure to high concentration of
toluene diisocyanate (TDI) cause cognitive
impairments?
?
“ In summary, psychometric testing using the Wechsler memory scale
? (1945) has shown a selective memory defect for relatively long-term
recall among the group of firemen who were clinically thought to be still
suffering from organic cerebral impairment four years after the fire.”
Neurological complications after a single severe exposure to toluene di-
isocyanate PAMELA M.LE QUESNE et al. British Journal of Industrial
Medicine . 1976;33;72-78

11. Catalogs & digital library
Catalogs
Bibliographic databases
!

12. Bibliographic databases
Pubmed ≠ Medline:
In addition to MEDLINE citations, PubMed also contains:
• In-process citations which provide a record for an article before it is indexed with MeSH and added to MEDLINE or converted to out-of-scope status.
• Citations that precede the date that a journal was selected for MEDLINE indexing (when supplied electronically by the publisher).
• Some OLDMEDLINE citations that have not yet been updated with current vocabulary and converted to MEDLINE status.
• Citations to articles that are out-of-scope (e.g., covering plate tectonics or astrophysics) from certain MEDLINE journals, primarily general science and general chemistry
journals, for which the life sciences articles are indexed with MeSH for MEDLINE.
• Citations to some additional life science journals that submit full text to PubMedCentral® and receive a qualitative review by NLM.
• Citations to author manuscripts of articles published by NIH-funded researchers.
• Citations for a subset of books available on the NCBI Bookshelf (a citation for both the book and each chapter or section of the book).
Source: http://www.nlm.nih.gov/pubs/factsheets/dif_med_pub.html , last consulted 1 October 2012
Why search beyond Pubmed?
# journals AND med AND psy AND emb unique
Medline 5,521 2,926
Psychinfo 596 2,208 1,402
Embase 2,360 571 3,982 1,412
Source http://www.ub.unimaas.nl/ub-fdgw/ubtest/co/m-p-e-coverage-overlap.htm, revised 11 March 2009

13. Guidelines & other resources of evidence

14. Questions?