I broadly differ with the hansonian take on medicine. I think metamed failed not because it offered more effective healing but went bust because medicine doesn't really demand healing; but rather that medicine is about healing, generally does this pretty well, and Metamed was unable to provide a significant edge in performance over standard medicine. (I should note I am a doctor, albeit a somewhat contrarian one. I wrote the 80k careers guide on medicine).

I think medicine is generally less fertile ground for hansonian signalling accounts, principally because health is so important for our life and happiness we're less willing to sacrifice it to preserve face (I'd wager it is an even better tax on bs than money). If the efficacy of marginal health spending is near zero in rich countries, that seems evidence in support of, 'medicine is really about healing' - we want to live healthily so much we chase the returns curve all the way to zero!

There are all manner of ways in which western world medicine does badly, but I think sometimes the faults are overblown, and the remainder are best explained by human failings rather than medicine being a sham practice:

1) My understanding of the algorithms for diagnosis is that although linear regressions and simple methods can beat humans at very precise diagnostic questions (e.g. 'Given these factors of a patient who is mentally ill, what is their likelihood of committing suicide?), humans still have better performance in messier (and more realistic) situations. It'd be surprising for IBM to unleash Watson on a very particular aspect of medicine (therapeutic choice in oncology) if simple methods could beat doctors across most of the board.

(I'd be very interested to see primary sources if my conviction is mistaken)

2) Medicine has become steadily more and more protocolized, and clinical decision rules, standard operating procedures and standards of care are proliferating rapidly. I agree this should have happened sooner: that Atul Gwande's surgical checklist happened within living memory is amazing, but it is catching on, and (mildly against hansonian explanations) has been propelled by better outcomes.

I can't speak for the US, but there are clear protocols in the UK about initial emergency management of heart attacks. Indeed, take a gander at the UK's 'NICE Pathways' which gives a flow chart on how to act in all circumstances where a heart attack is suspected.

3) I agree that the lack of efficacy information about individual doctors isn't great. Reliable data on this is far from trivial to acquire however, and that with doctors understandable self-interest not to be too closely monitored seems to explain this lacuna as well as the hansonian story. (Patients tend to want to know this information if it is available, which doesn't fit well with them colluding with their doctors and family in a medical ritual unconnected to their survival).

4) Over-treatment is rife, but the US is generally held up as an anti-examplar of this fault, and (at least judging by the anecdotes) medics in the UK are better (albeit still far from perfect) at flogging the patient to death with medical torture. Outside of this zero or negative margin, performance is better: it is unclear how much is attributable to medicine, but life expectancy, disease free life expectancy, and age-standardized mortality rates for most conditions are declining.

Now, why Metamed failed (I appreciate one should get basically no credit for predicting a start up will fail given this is the usual outcome, but I called it a long time ago):

Metamed's business model relied on there being a lot of low hanging fruit to pluck. That in many cases, a diagnosis or treatment would elude the clinician because they weren't appraised of the most recent evidence, were only able to deal in generalities rather than personalized recommendations, or that they just were less adept at synthesizing the evidence available.

If it were Metamed versus the average doctor - the one who spends next-to-no time reading academic papers, who is incredibly busy, stressed out, and so on, you'd be forgiven for thinking that metamed has an edge. However, medics (especially generalists) have long realized they have no hope of keeping abreast of a large medical literature on their own. Enter division of labour: they instead commission the relevant experts to survey, aggregate and summarize the current state of the evidence base, leaving them the simpler task of applying in their practice. To make sure it was up to date, they'd commission the experts to repeat this fairly often.

I mentioned NICE (National Institute of Clinical Excellence) earlier. They're a body in the UK who are responsible (inter alia) for deciding when drugs and treatments get funded on the NHS. They spend a vast amount of time on evidence synthesis and meta-analysis. To see what sort of work this produces google 'NICE {condition}'. An example for depression is here. Although I think the UK is world leading in this aspect, there are similar bodies in similar countries in other countries, as well as commercial organizations (e.g. Uptodate.)

Against this, Metamed never had any edge: they didn't have groups of subject matter experts to call upon for each condition or treatment in question, nor (despite a lot of mathsy inclination amongst them) did they by and large have parity in terms of meta-analysis, evidence synthesis and related skills. They were also outmatched in terms of quantity of man hours that could be deployed, and the great headstart NICE et al. already had. When their website was still up I looked at some of their example reports, and my view was they were significantly inferior to what you could get via NICE (for free!) or Uptodate or similar services for their lower fees.

MEtamed might have had a hope if in the course of producing these general evidence summaries, a lot of fine-grained data was being aggregated out to produce something 'one size fits all' - their edge would be going back to the original data to find out that although generally drug X is good for a condition, in ones particular case in virtue of age, genotype, or whatever else, drug Y is superior.

However, this data by and large does not exist: much of medicine is still at the stage of working out whether something works generally, rather than delving into differential response and efficacy. It is not clear it ever will - humans might be sufficiently similar to one another that for almost all of them one treatment will be the best. The general success of increasing protocolization in medicine is some further weak evidence of this point.

I generally adduce meta-med as an example of rationalist overconfidence. That insurgent Bayesians can just trounce relevant professionals in terms of what they purport to do thanks to signalling etc. But again, given the expectation was for it to fail (as most start ups do), this doesn't provide evidence. If it had succeeded, I'd have updated much more strongly in the magic of rationalism meaning you can win and the world being generally dysfunctional.