Perspectives on the importance of evidence in medicine

When this week's host of Grand Rounds, the Signout blog, announced a theme edition dedicated to "the interface of evidence with health and health care," I jumped up and down a bit in excitement, and today have decided to dedicate a special post to the occasion. Shameless sucking up, I know, but in any case, here are a few recent items that articulate the importance of evidence in health care.

The British Medical Journal, which is committed to promoting evidence-based medicine, has an article this month by Kay Dickersin, director of the US Cochrane Center, and colleagues on the importance of evidence-based medicine. The Cochrane Collaboration is an international effort to produce systematic reviews of evidence on clinical questions; check out their website, which offers free summaries of all of their reviews.

Anyway, here's the introduction to the BMJ article, whose content is available free, at least this month.

Evidence based medicine is healthcare practice that is based on integrating knowledge gained from the best available research evidence, clinical expertise, and patients' values and circumstances. It is curious, even shocking, that the adjective "evidence based" is needed. The public must wonder on what basis medical decisions are made otherwise. Is it intuition? Magic? The public must also wonder what happens to the research evidence in which they have invested—either directly through taxes or indirectly through buying drugs and other medical products—if it is not guiding clinical practice.

How could something so intuitively obvious to lay people not be similarly viewed by clinicians? And how could this medical milestone be so misunderstood by some? Critics of evidence based medicine worry that it dictates a single "right" way to practise, despite differences among patients; that some self appointed group of "experts" will declare only one type of study to be useful; or that healthcare decisions will be made solely on the basis of costs and cost savings. Giving a name to evidence based medicine and, now, awarding it milestone status could help everyone to realise that it is about making decisions that are based on the best available evidence, not dictating what clinicians do.

My regular readers know by now how obsessed I am with the cost of health care. Fed Chairman Ben Bernanke echoed fears about health care costs this week, pointing out how programs like Medicare, Medicaid, and Social Security will become a huge draw on our economy in years to come, as baby boomers age. It's true, of course, that costs are increasing. The value we put on health care is in part for society to decide, but my perspective is that better use of evidence-based medicine can lower costs for everyone by preventing the wasteful use of procedures, tests, and interventions that don't work (not to mention the aforemention health benefits of evidence-based medicine). Here's a press release about a new paper in Health Affairs that argues just that, more knowledgeably than I can.

The Effect Measure blog this week aimed to put Bernanke's warnings in perspective, at least in 2007 terms; check out the annual costs of entitlements compared to the war in Iraq. Nice graphic, but doesn't put to rest the question of future health care costs.

Finally, here's a plug for a blog I like, The CAM Report, which this week reported that the allopathic (mainstream) health community is now starting to argue in the mainstream medical press (in this case, JAMA) for rigorous evaluation of the evidence behind complementary and alternative medicine (CAM), expanded use of meta-analyses, and consistent reporting requirements for CAM studies.

The CAM Report gives regular updates on new research on CAM, including the good, the bad, and the ugly. If you're interested in the lively debate surrounding the evidentiary basis of CAM, you'll enjoy Respectful Insolence, by Orac; here's a typical post on this debate. I once asked Orac whether we shouldn't be equally concerned about the evidence for allopathic medicine; he agreed, but countered that allopathic medicine is at least based on sound biologically based theory, unlike much complementary and alternative medicine. Really? I've been trying, since then, to come up with examples where allopathic modalities do not have a sound theoretical/biological basis. Anyone?