Thursday, February 11, 2010

Evidence-based... inquisition?

Remember the trial a couple of years ago that showed that group support participation was associated with prolonged survival among women with metastatic breast cancer? I've thought a lot about that over the years. Isn't it interesting that something as simple as a supportive environment can make a difference in what researchers consider to be the hardest endpoint there is: survival? In our dualistic view of the human organism, we think of support as acting in the realm of the psyche, and not the physical. And yet, here is the evidence of a psychological exposure somehow making a tangible physiologic difference.

Now, how do we do evidence-based medicine? Well, we look for clinical studies that tell us whether and how well a treatment works for a particular condition. For the rabid evidenistas among us the most valid design to provide such evidence is a randomized controlled trial, since it has the most internal validity (i.e., we are in fact likely to be studying what we think we are studying). When we pat ourselves on the back on a randomization well done, we cite the balance in the fairly obvious demographic and clinical characteristics in the two (or more) comparator groups, namely, age, gender, comorbidities, the burden of acute illness, and the like. We rarely bother with their social or psychological milieu; in fact edging up to evaluating that may be viewed by some as engaging in quackery. Well, true, these exposures are ephemeral and somewhat abstract, but look at the breast cancer study... Just because it is difficult to study and we do not have validated tools for them currently, does not mean that we can ignore, or worse yet, disparage, their potential influence. Isn't there a saying to the effect that we cannot discover that which we do not currently have the tools to understand?

And speaking of inadequate tools, a related sticky wicket comes to mind: heterogeneity. I say it is related because we do not even dare look at the underlying non-physiologic heterogeneity as I mentioned above. What may surprise the uninitiated more, however, is the fact that we do not have good tools to identify physiologic heterogeneity. And as most appreciate, heterogeneity demands large numbers of subjects to study to get a detectable effect. In fact, our research enterprise is set up to do mammoth studies for often a miniscule difference (think cardiology trials requiring 20,000 patients to demonstrate a fall in mortality from 0.5% to 0.25%). It is very likely that by using this sledge hammer method to craft the fine jewel of evidence we are missing huge chunks of useful information.

And if this is the case for our Western paradigm of medical treatment, how does it play out in our study of Eastern and other non-traditional modalities? Don't take me wrong; I am not suggesting having blind faith in homeopathy, for example. But I am curious about how cultural psychology may influence responses to such treatments as Ayurvedic medicine, say. Perhaps it only "works" in conjunction with meditation and yoga? An "Eastern bundle" anyone?

The point is I do not know the answers to these questions. What I do know is that with our approach to evidence building we are looking at a vast castle through a key hole: we are only seeing small swaths of reality. My final point is this: because so much remains in the dark, we need to be humble when exploring evidentiary basis for any intervention. A parochial attitude equating gaps in our understanding to lack of effectiveness makes us seem like the Inquisition persecuting Galileo for defining an alternate reality which turned out in the long run to be the truth we live by.  

2 comments:

  1. Such wonderful points Marya and something that I've written about a few times, both on Disruptive Women in Healthcare and Flashfree. What I've seen in my research is that when Western methodology starts to incorporate some of the inherent philosophies of Eastern practice, such as individualization, the results change. One study I consistently point to is ACUFLASH, and evolving data continue to show benefit.

    Thanks for this post - it's critical to open the minds of the allopathic and scientific communities to new ways of thinking.

    ReplyDelete
  2. Thanks for your comment, Liz! Yes, ACUFLASH is an interesting case, where our Western methods showed somewhat dubious results. And people are using the "P" word, of course. But I say, what is wrong with leveraging the placebo effect? We actually do it in Western medicine a lot. And if we are worried about reimbursing something that has not been definitively shown to "work", how about robotic prostate surgery? (http://www.nytimes.com/2010/02/14/health/14robot.html?pagewanted=1&hp)

    ReplyDelete