I read a thought-provoking question last week: "Does adherence to guidelines really have a positive impact on healthcare?"
Evidence-based medicine (EBM) was just emerging as I qualified, so has always been with me. The five steps of EBM in practice were first described in 1992 and the Cochrane Collaboration was founded in 1993. Cochrane's suggestion was that the methods used to prepare and maintain reviews of controlled trials in pregnancy and childbirth, should be applied more widely.
Working out what is an effect of 20 years of evidence-based practice from the many other factors affecting the population (and its health) is extremely difficult, but Neal Maskrey (GP and Professor of evidence-informed decision making at Keele University) points out that there has been a shift in our thinking that we may underestimate. "You don't see people getting antibiotics, paracetamol, and a decongestant for a cold anymore because we unconsciously follow the evidence that they don't do any good. We don't measure that change and demonstrate that EBM 'works.' In skilled clinicians' hands, EBM has imperceptibly become an integral and positive part of providing care."
I believe there has been a huge shift in our thinking and it's all a very long way from 'you do it, because it's always worked for your consultant (as far as he can remember).' It also feels much better to have a discussion with a patient that contains, "There is good evidence that X works in this situation", rather than "I think we should try X!"
Professor Maskrey also queries whether it would be better to question 'variable quality of guidelines' rather than their efficacy. He states that "only 5% have a described search strategy, grade the evidence, and report the type of stakeholders".
Part of my role as editor is to search through major societies and guideline producers, to keep us up-to-date. I have a list of 100+ sources, in addition to regular updates from Dynamed on potential (high-quality) practice-changing papers, the Lancet, NEJM and the BMJ. [I like reading.] High quality means, adhering to the EBM principles and certainly having a stated search strategy.
EBM however, is not without criticism. It produces quantitative research, especially from randomised controlled trials (RCTs), which means that the results may not be relevant for all treatment situations. Certain population demographics tend to be under-researched (racial minorities and people with co-morbid diseases), and so general statements drawn from RCTs should be guarded. Also, as per the recent high-profile BMJ campaign, not all evidence from an RCT is always made accessible, so treatment effectiveness reported from RCTs may be different from that achieved in routine clinical practice. If only 'selected' evidence is published, how do we know the true picture and how do we stop our cynical side questioning motives?
Published studies may also not be representative of all the studies completed on a given topic (published and unpublished), or may be unreliable due to the different study conditions and variables. Many high- profile medics have pointed out that as RCTs are expensive, research topics are highly motivated according to the sponsor's interests, often 'big pharma'. How many high-quality papers have you seen recently that looked at something that couldn't be commercialised? There may be cheap solutions out there, but how will we ever know if no one stands to make a profit?
EBM should not preclude clinicians from using their personal experience in deciding how to treat their patient. It has been suggested that "the knowledge gained from clinical research does not directly answer the primary clinical question of what is best for the patient at hand" and suggests that EBM should not discount the value of clinical experience. Another suggestion is that "the practice of evidence-based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research". And that (I guess) is why you visit our pages. For our latest evidence-based content updates (including lung cancer, osteoarthritis, domestic violence) click here.