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Friday, September 19, 2014


There is nothing wrong with trying to improve the value of health care. But better value will depend as much on doing more of what’s good as it will upon doing less of what’s bad ... You don’t bill for talking to a patient about how he wants to die. There’s no code for providing reassurance rather than ordering a test. And, for all the talk about transforming our health-care system from one that treats illness to one that promotes health, no one pays you to talk to patients about how they might lead healthier lives.

- Lisa Rosenbaum, What Big Data Can't tell us about health care
Props to The Incidental Economist for the heads-up on her writings. Below, another interesting cite from another of her New Yorker articles, apropos of "Big Data" and EBM:
Because cardiovascular disease is so common, cardiologists have been able to study millions of patients, leading to what is arguably the most robust evidence base in all of clinical medicine. Yet despite innumerable outstanding clinical trials, we are always held back by what we don’t know.

Consider the claim that medications are as good as stents for treatment of stable coronary artery disease. This is the idea upon which most accusations about the overuse of stents are predicated. Several studies support this assertion, but the seminal one is the COURAGE trial, which randomly assigned patients with stable blockages to either medication or a stent. The study found that those treated with medications lived just as long as those with stents. COURAGE is a super-star trial, the best of its kind. So why can’t we say, once and for all, that it’s inappropriate to use stents for patients with stable coronary disease?

The answer is that it’s because such a statement is a colossal oversimplification. The fundamental challenge of translating data into practice is what we call generalizability: Can we extrapolate the findings from a trial to real life? If you are a doctor who is trying to practice evidence-based care, the first thing you want to ask yourself is, Would my patient have been enrolled in the trial? Sun Kim would not have been eligible for the COURAGE trial, which excluded all patients with high-risk features—or nine out of ten otherwise eligible patients.

But let’s say that your patient is among the ten per cent who would have been enrolled in COURAGE. Can’t you say now, with certainty, that your patient should not get a stent? Still no. Real life rarely resembles clinical trials, which are, by definition, rarefied environments—well-oiled machines with incredible depth of resources and a staff to orchestrate patient care.

If, as in the case of COURAGE, you set out to show that medications are as effective as stents in treating chronic disease, you want to make sure that the patients in the trial are actually taking those medications. In reality, the rate of adherence to medications is about fifty per cent, but COURAGE not only provided medications for free—it also hired nurse managers who saw patients regularly and adjusted dosages. Not only did these patients adhere to medications at a far higher rate than patients usually do—this adherence also translated to excellent blood pressure and cholesterol control.

If it’s hard to apply the findings from any one trial to the treatment of a particular patient, it’s harder still to use data from many trials to create guidelines that can be applied to any patient. When a group of expert cardiologists were asked to do just that, they recognized that there are many factors to be considered in addition to medication—including the acuity of the disease, the patient’s degree of chest pain, the results of stress tests, and which of four main arteries are blocked. When you account for all of these factors, you come up with over four thousand clinical scenarios for which stenting may or may not be appropriate, many of which can’t be mapped precisely to a clinical trial.

It was in these gaps between data and life where I lost Sun Kim. There is no guideline that says, “This is how you manage an elderly man who asks nothing of anyone, who may or may not be taking his medications, and who has difficulty coming to see you because he vomits every time he gets on the bus.” In a world with infinite resources, we could conduct clinical trials to address every permutation of coronary disease and every circumstance. But that’s not the world we live in. And in our world, I reached a point where I could not keep Sun Kim out of the hospital.
 - When Is a Medical Treatment Unnecessary?
Good stuff.


I'll be there early Monday morning. Register here if you've not already done so.  Should be a very interesting event. My 2013 M-W coverage, here, here, and here. I also went to the Sunday prelims last year.

More to come...

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