Clearly it is crucial that if one is going to base health care decisions on "evidence" found in various information sources, that the validity of this information can be assessed. The International Congress on Biomedical Peer Review and Global Communications <http://www.ama-assn.org/public/peer/peerhome.htm > aimed to evaluate peer review as a tool for assessing the quality and credibility of scientific information, to help close the information gap between the East and West and the South and North, and to increase the efficiency and effectiveness of global biomedical communications. The strength of evidence depends on many factors, and no discussion on evidence-based medicine would be complete without mention of the efforts of the Cochrane Collaboration.

"To make well-informed decisions about health care, clinicians, policy makers, funders and patients need access to reliable evidence about the effects of health care interventions. Unfortunately people are often not aware of the evidence that is available, the evidence is disorganised and inaccessible, or it simply does not exist." (About the Cochrane Collaboration, South African Health Technology Monitor, Vol 1, No 1, July 1997, Medical Research Council – monitor@eagle.mrc.ac.za )

The Cochrane Collaboration < http://hiru.mcmaster.ca/cochrane > facilitates the creation, review, maintenance and dissemination of systematic overviews of the effects of health care interventions.

The Database of Abstracts of Reviews of Effectiveness (DARE) < http://www.york.ac.uk/inst/crd/info > is a collection of records of good quality research reviews of the effectiveness of health care interventions, and the management and organisation of health services.

Whilst reviews would be expected to provide a more balanced view of the evidence, it is clear that techniques such as meta-analysis are still beset by problems (Meta-analysis: Unresolved issues and future developments. BMJ 1998;316:221-225 (17 January), http://www.bmj.com/ ). We also have to be careful that "evidence" doesn’t become the only focus. As Kerridge et al point out, at the individual level, the presence of reliable evidence does not ensure that better decisions will be made, and at the level of national policy determination and resource allocation evidence is available for relatively few interventions. Looking only to evidence-based medicine is seeking simplistic solutions to inherently complex problems (BMJ 1998;316:1151 http://www.bmj.com ).

Evidence based medicine is really a principle that should be applied to all health professions and aspects of health care. Evidence based drug therapy is just one example of particular relevance to the pharmacist.

A number of sites look at the pharmacological implications of evidence based practice:

National Prescribing Centre [UK] < http://www.npc.co.uk >

Therapeutics Initiative Home Page [Canada] < http://www.interchg.ubc.ca/jauca/ >

PreMeC [New Zealand] < http://www.premec.org.nz >

Evidence based health (EBH) is the application of critical appraisal to problems in health care. This list is for teachers and practitioners in health related fields. To subscribe send an email with the message join evidence-based-health to mailbase@mailbase.ac.uk

Health A to Z http://www.healthatoz.com

MedwebSA http://www.medwebsa.co.za  (in development, useful potential)

Medical World Search http://www.mwsearch.com

MedFinder Smart Medical Web Search http://www.netmedicine.com/medfinder.htm

MedSite Medical Search Engine http://www.medsite.com

CliniWeb http://www.ohsu.edu/cliniweb/   is an index and table of contents to clinical information on the Web.

There has been a proliferation of search engines on the Internet. Many of them index billions of pages, which are visited regularly by "spiders" or "robots" (eg HotBot), while others adopt a more catalogue-oriented approach (eg Yahoo) where entries are organised by broad categories which drill down. There are also variations in the power of the search engines, some allowing complex Boolean searches, categorisation by location and other factors. The search engine which I personally have found to have the best mix of speed, ease of use and functionality is HotBot.

HotBot http://hotbot.com

Altavista http://www.altavista.digital.com

Yahoo http://www.yahoo.com

DogPile http://www.dogpile.com

African / South African Search Sites:

Ananzi http://www.ananzi.co.za

Internet Gateway to South Africa http://www.minotaur.marques.co.za

Rubani http://www.rubani.com

ZaZoo http://www.mweb.co.za/zazoo

Medical Matrix < http://www.medmatrix.org > has ranked, peer-reviewed, annotated, updated clinical medicine resources

The Health Information Research Unit < http://hiru.mcmaster.ca/ > studies the phenomenology of health information, develops information tools to support evidence-based medicine and evaluates informational health interventions

In a short article on "The changing face of Information: Balancing the power of new techniques versus the credibility of established methodology" http://www.healthlink.org.za/hlink/info/internet1.htm , some of these issues were addressed:

• Information retrieval and dissemination are essential features of research
• The Internet is revolutionising the way information is used
• With the power and ease of use of the Internet, come information overload and disinformation, which threaten to discredit the technology.
• Regulation will not ensure ethical, accurate health information - adherence to codes of conduct and education of the user to critically evaluate information is required