Evidence-Based Medicine

In order to obtain the best evidence, an electronic-based search of answers to
the formulated questions in sources of «ready made» evidence, is the easiest
and fastest way. These sources include the Cochrane Library, Best Evidence,
ACP Journal Club, Clinical Evidence; Infopoems, DARE and others. The main
obstacle against using these resources is cost of subscription (that they are
not free).
If these sources are not available or if the answers of the search question
was not found in them, one would have to search sources of primary evidence
(original articles and systematic reviews). These articles can be found in
electronic databases (e.g. Medline, EMBASE, SAM) and Electronic journals
(e.g. Bandolier, Journal of Evidence Based medicine, JAMA, NEJM, Lancet,
BMJ etc.).
Critically appraising the evidence
The practitioner needs to develop a sorting strategy in reviewing the available
literature so as to remove relevant from irrelevant materials. Then he should
decide whether the article is well conducted and can be used or not.
Several checklists have been developed to help make this process easy,
systematic and more or less reproducible. Usually they focus on three man
areas; validity, results and applicability. Validity or closeness to truth usually
examines the methodology of the article
Critical appraisal
For any clinician, the real key to assessing the usefulness of a clinical study
and interpreting the results to an area of work is through the process of critical
appraisal. This is a method of assessing and interpreting the evidence by
systematically considering its validity, results and relevance to the area of
work considered.
The Critical Appraisal Skills helps health service professionals and decisionmakers
develop skills in appraising evidence about clinical effectiveness. Its
process uses three broad issues that should be considered when appraising a
review article:
• Are the results of the review valid
• What are the results
• Will the results help locally
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