Doctors have often joked that about half of what they are taught in medical school is wrong-- but no one knows which half. And indeed, the history of medicine is filled with highly-touted "miracle cures" that everyone "knew" to be effective-- but which turned out upon rigorous examination to be not only useless, but harmful, even deadly.
In an attempt to address this situation, the concept of "evidence-based medicine" was born. Although many people imbue medicine with the aura of science, it is only within the last five decades or so that genuinely scientific principles have begun to be widely applied.
Unfortunately, however, both the right and the left have been attacking scientific medicine lately. From the right, the "intelligent design" movement has attempted to redefine science and the Bush administration has dismissed, distorted and even attempted in some cases to suppress research that doesn't support its political positions in medical controversies from AIDS prevention to sex education to stem cell research. Corporate influence on medical research has also grown, unchecked.
However, the left's attitude toward science has unfortunately enabled and empowered these attacks because it refuses to see scientific knowledge as superior to that gained by other means.
It would be hard to find a better example of this sort of fuzzy thinking (that has been gleefully dissected by the blogosphere: see my colleague Trevor Butterworth at stats, pharyngula , and badscience, just for starters), than this recent paper. Titled "Deconstructing the evidence-based discourse in health sciences: truth, power and fascism," it was published (presumably as a self-critique) in the September issue of International Journal of Evidence-Based Health Care.
The article claims that, "...the evidence-based movement in the health sciences is outrageously exclusionary and dangerously normative with regards to scientific knowledge. As such, we assert that the evidence-based movement in health sciences constitutes a good example of microfascism at play in the contemporary scientific arena."
The goal of this "fascistic" enterprise is simply for physicians to start by applying the best science known (for example, beginning by trying a drug shown by multiple, randomized clinical trials to be effective 60% of the time) and then using personal, clinical knowledge to fine-tune and individualize treatment (this particular patient shares characteristics with other patients whom I've seen fail on this drug, so I will switch rapidly if I don't see immediate efficacy).
This way, the patient gets the benefit of both the collective scientific wisdom of the field (which is less subject to individual biases because the scientific method is aimed at eliminating as many as possible) and the doctor's own personal experience (which is honed by practice, but is still subject to all the normal human biases).
Although the notion of scientific medicine and using concepts like randomization, blinding and large samples to test medications and therapies goes back to the 1940's and in some instances, earlier, the idea of systematically applying the knowledge gained through clinical trials is of much more recent vintage. Historians of medicine credit British epidemiologist Archie Cochrane with founding the modern evidence-based medicine movement in 1972, when he wrote a book that laid out its principles.
The term "evidence-based medicine" itself, however, does not appear in the medical literature until 1992. In 1993, the Cochrane Collaboration (named for the epidemiologist) was founded to systematically review the literature and disseminate its conclusions to make the best possible evidence widely available to practitioners.
So, what this paper is arguing is that rather than use the systematically organized and analyzed data gathered from the best research available, medicine should instead "work towards the creation of a space of freedom (of thought)," that would not ostracize "those with 'deviant' forms of knowledge, [ label] them as rebels" and reject "their work as scientifically unsound."
It says: "The evidence-based enterprise invented by the Cochrane Group has captivated our thinking for too long, creating for itself an enchanting image that reaches out to researchers and scholars. However, in the name of efficiency, effectiveness and convenience, it simplistically supplants all heterogeneous thinking with a singular and totalising ideology. The all-embracing economy of such ideology lends the Cochrane Group's disciples a profound sense of entitlement, what they take as a universal right to control the scientific agenda."
In other words, science is just another voice in the dialogue and the claims of people who, for example, have nothing more than anecdotes to back their proposed treatments or policies, should be given equal weight to those who have used scientific techniques to eliminate biases from their data as much as possible. This is not to say that evidence-based medicine is perfect-- but the scientific method is the only thing that reliably and consistently shows us "what works" and "what doesn't." It is the only methodology deliberately designed to avoid the biases that consistently make us see only what we want to see and hear only what we want to hear.
Can corporate and other influences affect what science finds and what research is published? Absolutely. But if we are to buy the logic of the authors of this paper, my "deviant" claim that standing on my head cured my cancer is just as valid as ten double-blind controlled studies systematically reviewed by a panel of independent experts.
If the left is to have any credibility in forging a "reality based" politics, it is going to have to elevate rigorous science and critical thought above claims that have not been exhaustively tested. It is valid to critique science and to probe for biases that have managed to resist controls. But if you abandon the idea that science has any extra weight entirely, you cannot rationally argue against intelligent design or quack cures or policies that demonstrably hurt people. After all, your claims are just another equally valid "perspective." Enough!