EBM anyone? Yes, but which one?

I recently saw a tweet by a German homeopath stating that ‘homeopathy is 100% experienced based medicine’. It made me think and realise that there is not just one EBM, there are, in fact, at least three EBMs!

1. Experience based medicine
2. Eminence based medicine
3. Evidence based medicine

I will start with the type which I encountered first when studying medicine all those years ago.

EMINENCE BASED MEDICINE

German healthcare was at the time – 1970s – deeply steeped in this variety of EBM. What the professor said was right, and there was no discussion about it. I don’t even know how my teachers would have reacted, if we had challenged their wisdom, because nobody ever did; it just did not occur to us.

Personally, I never got along too well with this type of EBM. I found it stifling, and this feeling might have contributed to my first ‘escape’ to England in 1979. In the UK, I felt, things were refreshingly different (see also my recent obituary of my former boss).

EXPERIENCE BASED MEDICINE

So-called alternative medicine (SCAM) is almost entirely based on this type of EBM. Practitioners of SCAM pride themselves of their experience and are convinced that it outweighs evidence any time. They rarely miss an occasion to stress that their treatment as stood the test of time. And as such it does not require evidence; if SCAM did not work, it would not have survived all these years.

Little do they know that the appeal to tradition is a logical fallacy. And little do they care that the long tradition of their SCAMs might just signal how obsolete their treatments truly are. Hundreds (homeopathy) or thousands (acupuncture) of years ago, we had little knowledge about physiology, pathology, etc., and clinicians had to make do with the little that got. Seen in this light, experience based medicine is a negative label that indicates the fact that the treatments are likely to be obsolete and out-dated.

EVIDENCE BASED MEDICINE

Providers of SCAM have a deeply rooted dislike for the word evidence. The reason is simple: their SCAMs are usually very shy on evidence; little wonder that they like to focus on experience instead. Yet, try to explain the concept of evidence to someone neutral like a barman, for instance – whenever I made this attempt, I was interrupted by him saying: ‘Hold on, are you saying that before EBM you did not depend on evidence? This is frightening! What on earth did you rely on then?’

It is indeed not logical to rely on eminence or on experience, in my view. And therefore, I have stopped explaining EBM to people who have common sense, like my barman. Let’s try something else instead: imagine you are seriously ill and are able to chose between three clinician who are each the leading head in their type of EMB.

THE EMINENCE IS A PROFESSOR MANY TIMES OVER AND SIMPLY KNOWS THAT HE IS ALWAYS RIGHT

Personally, I would run a mile. I have seen too many of those blundering through the wards of university hospitals. He never makes a mistake, except that things do go wrong quite often; and when they do, it is the fault of some underling, of course.

THE EXPERIENCED CLINICIAN WITH YEARS OF PRACTICE WHO HAS SEEN IT ALL AND HAS ALL THE ANSWERS

With a bit of bad luck, he might be a homeopath. He will tell you endlessly of cases that were similar to yours. Occasionally, there was an aggravation (which, of course, is a good sign in his view), but in the end he cured them all with his treatments that had stood the test of time. He has excellent bedside manners, a lot of charisma, and is a good listener. Who was it that said: “the three most dangerous words in medicine are IN MY EXPERIENCE”?

Yes, you guessed it: run and don’t turn back!

THE CLINICIAN WHO KNOWS WHAT THE CURRENT BEST EVIDENCE HAS TO OFFER

He might not be all that charismatic, perhaps he even is a bit abrupt. But he will know the latest developments and weigh the risks of all therapeutic options against their benefits.

But hold on, my barman would interrupt at this point, this is not either or. One can have both experience and evidence!

I told you my barman was clever. The definition of evidence based medicine is not healthcare based on up-to date knowledge, it is the integration of best research evidence with clinical expertise and patient values. It thus rests on three pillars: external evidence, ideally from systematic reviews, the clinician’s experience, and the patient’s preferences.

Therefore, my barman and I agree that eminence based medicine is highly questionable, experience based medicine can be outright dangerous, and evidence based medicine is the only EBM version that does make sense.