Thursday, October 14, 2010

The reality of "science-based medicine"

Dr. Novella continues with his egregious oversimplification of the concept of science-based medicine here. I again felt compelled to respond. And given my previous difficulties with getting my responses accepted by the web site, I thought I'd post it here too. Tell me what you think.

Dear Dr. Novella,

Once again I have to agree with some of your premises, but disagree with your misguided leaps of illogic. I agree that if a modality has not been proven effective, the only way it should be left alone to be used by the public is if it has been shown to be safe. Alas, the risk-benefit equation is an individual choice, and we cannot impose our quantitative bottom line on it. Your assertion that scientific medicine is being eschewed because of acceptance of alternative modalities is as flawed as maintaining that a rain dance brings on rain. I know you said the relationship was complicated, but let's be honest: you think that CAM acceptance is killing allopathic medicine.

Now, let's get on to "proof" in science-based medicine. As you well know, while we do have evidence for efficacy and safety of some modalities, many are grandfathered without any science. Even those that are shown to have acceptable efficacy and safety profiles as mandated by the FDA, are arguably (and many do argue) not all that. There is an important concept in clinical science of heterogeneous response to treatment, HTE, which I have addressed extensively on my blog. I did not make it up, it is very real, and it is this phenomenon that makes it difficult to predict how an individual will respond to a particular intervention. This confounds much of what we think is God's own word on what is supposed to work in allopathic medicine.

Finally, do you really think that agents that are approved based on a 2-week prolongation of median survival in a desperately ill population of patients are used because of their supposed scientific merit? I would have to argue that there is a lot of subcortical emotional thinking that goes into these decisions. Can you really prove to me that a 2-week increase in median survival is not tantamount to placebo effect, aka type I error? Yet this is science-based. I think if I had a horrible disease, I might opt for acupuncture to make me feel better in the weeks I have left rather than rely on this kind of "science" to prolong my misery by 2 weeks.

Bottom line, we need to appreciate that none of the science is all that straightforward. Let us not dumb down the arguments and create false dichotomies. If we do, no one wins.


  1. Good summary Marya. Too often the term 'science' is used as an authoritative trademark rather than indicating what it really is, a humbly questioning and critical striving to understand the world. The fact that some commentators such as in this example so relentlessly pursue 'woo' issues while largely ignoring many of the extremely difficult and complex controversies within mainstream science makes me wonder what their motivation really is; to expand human understanding or to pursue a social aim of confronting and defeating the now socially-powerful advocates of alternative medicine. These aren't the same objectives.

    I probably don't disagree as strongly as you about the possible harms of alternative medicine (anti-vaccine loons are pretty bad), I just don't see our role in the medical establishment to be to stamp out these heinous evils through all means available including government intervention. I don't think we have the power to completely change some of these beliefs in others and efforts like this example are probably counter-productive anyway. We can provide information and recommendation and these are likely work best in all ways if delivered humbly and engagedly. I've amended the one post on my blog referring to acupuncture to make this crystal clear.

    The tone of dogmatic paternalism which I'm sure is partly what set you off also makes me wonder what the author's mainstream clinical practice is like, since to my mind dogmatic paternalism is the enemy of good clinical practice. For whatever controversies exist in current neurology practice does he also come down hard on one side, overgeneralising research findings rather than taking interest in fine-grained detail, all fuelled by a personal disdain for those who practice in ways alternative to his own? This is speculation but the linked commentary makes me feel it is more likely the case in this sort of clinician than average.

    I of course have my own angle and I don't think the rise of the movement of 'evidence-based medicine' has been helpful in restraining complacent authoritativeness. This is ironic since a clear aim of the movement was to devalue the social authority of established 'experts'. Sadly I feel the overall effect has been negative and it has merely provided a framework for anyone to aspire to a position of discussion-stymieing authority, in place of the crusty ancient professors whose pronouncements were previously taken as gospel.

  2. Dear Ed, thanks for your thoughtful comment. I could not agree with you more, and we really need to bring humbleness back to the profession.

    One issue I want to expand on that you bring up is my attitude towards CAM. First, I think that the umbrella of CAM is way too broad and heterogeneous to be a coherent rubric. The potential value of traditional Chinese medicine may be quite different from healing crystals, say. Second, as for vaccines, there are a number of issues. I am a great believer in vaccination as a public health measure. I do think that we have gone a bit overboard with vaccines such a chicken pox and HPV, where economic expediency seems to have trumped the clinical risk-benefit equation. And while I am truly appalled by the demagoguery surrounding the vaccination debate, in the same vein as acknowledging the realities of our science, I would like to acknowledge the nuances of the vaccine issues.

    Too often I feel that the "science-based" zealots lump everyone's objections to their dogma into the ignorance bucket and resort to insults and intellectual dishonesty to defeat the opposition. In this way many dichotomies are created which conceal the nuances of potentially enriching discussions. I concede that I am incensed by these attitudes, and I will try harder in the future to keep my equanimity.

    As always, thanks for your well thought-out comments -- they challenge me to keep examining my assumptions!


  3. Crikey! I have been meaning to respond for a while and now you have put up about 4 new posts since this one! No way I could be that productive, I bet you have full-time clinical, research and teaching work as well.

    Anyway first and most important don't try to keep your equanimity. Proper vigorous discussion entails that no one is afraid of someone getting het up or afraid of offending the reader. Though dogma is bad passion is great, I reckon.

    Good point about vaccination not being one simple issue. Varicella and HPV vaccines are less critical than pertussis and pneumococcal. In general I'm more nihilistic and disengaged about CAM than most doctors, and probably more than you'd expect. What I mean is that I don't feel it's my role to address CAM either way. Many seem to feel that they should discuss or support or advocate with regard to their patients' CAM use and should therefore try to understand it better. I don't; patients rarely ask me about it and I never raise it. On the rare occasion it is raised my only response is simply 'sorry, I don't know anything about that'. Some might feel this a bit negligent but to me I genuinely value patient autonomy and that cuts both ways. I don't condemn patients for pursuing CAM and I don't feel obliged to help them out with it either. I can confidently say that while discussing or promoting vaccinations or any other alternative view on medicine I've NEVER invoked 'science' and 'scientific evidence' to try to bully the listener into behaviour change.

    This has become a pointed issue in the child protection work I've done in the past, where a specialist has been clearly angry with parents for pursuing CAM against their orders or simply not following their orders to the letter. Since they lack the legal and ethical discipline which child protection work necessitates they think they can call on the child protection paediatrician to use the power of the state to enforce their wishes. If the child is not in clear danger of significant harm they are quickly set straight (the few cases where parents really are horribly negligent and prosecuted are a small minority of those referred to us).

    Anyway I'd better get on and look at the rest of your posts or I'll fall even more behind. I can't seem to get my name on my responses on blogspot, just 'theykilledkenny', which is annoying so sorry about that.

  4. Ooh maybe should be still more specific about CAM as an area I don't address with patients. All I mean by CAM is theories and practices not covered by mainstream medicine ie. that taught in medical schools and discussed in medical journals. A deliberately vague definition. As it turns out I don't myself believe in any of the range of CAM theoretical frameworks and have not taken the time to look at them in more detail; but I don't believe a lot of what I read in medical journals either.

  5. Thanks, Ed. What did you think of the recent Atlantic article about John Ioannidis' work? I did a post on it this past week titled "Lies and more lies: Are all lies created equal?"

  6. Marya,

    I think you really hit the nail on the head here. With Dr. Novella and his crew, there certainly appears to be a pattern of gross simplification and as you stated "leaps of logic" when it comes to accepting evidence. The behaviour is almost biblical in nature accompanied by the casual ommissions of acknowledging the limitations that comes along with much of it.

    My own observation supports your characterization of a dogmatic or at least belief based dismissal of alternate modalities based alone on an arbitrary definition of what they deem scientifically plausible.

  7. Thanks, Schwarts, I think that these people are quite sincere about their love for science-based medicine. But then again, so is the Pope about his love for The Church.