The benefits of statistic-based medical diagnoses

A recent eSkeptic reviewed ‘How Doctors Think’ and, amongst some fairly strong criticisms of the book, mentions ‘decision aids’ – algorithm-based methods of diagnosis:

Most doctors do not like decision aids. They rob them of much of their power and prestige. Why go through medical school and accrue a six-figure debt if you’re simply going to use a computer to make diagnoses? One study famously showed that a successful predictive instrument for acute ischemic heart disease (which reduced the false positive rate from 71% to 0) was, after its use in randomized trials, all but discarded by doctors (only 2.8% of the sample continued to use it).5 It is no secret many doctors despise evidence-based medicine. It is impersonal “cookbook medicine.” It is “dehumanizing,” treating people like statistics. Patients do not like it either. They think less of doctors’ abilities who rely on such aids.6

The problem is that it is usually in patients’ best interest to be treated like a “statistic.” Doctors cannot outperform mechanical diagnoses because their own diagnoses are inconsistent. An algorithm guarantees the same input results in the same output, and whether one likes this or not, this maximizes accuracy. If the exact same information results in variable and individual output, error will increase. However, the psychological baggage associated with the use of statistics in medicine (doctors’ pride and patients’ insistence on “certainty”) makes this a difficult issue to overcome.

I can see how that would suck, from a doctor’s perspective. But that’s quite the statistic on the heart disease prediction. Maybe this is the way of the future: statistical techniques that apply to the majority, with human oversight to spot the minority cases.

Having said that, I was hearing this evening how current advances in the understanding of disease at the genetic level are going to lead to much more personalised medicine in the next 10-20 years. Which is cool. It was Francis Collins who said it, mind, and his reasoning skills elsewhere in the interview were somewhat suspect, but he nevertheless knows more about it than me 🙂