Certainly we would get more bang for our buck from engineering and public health than from medicine on the margin, but the effects of cure are near and the effects of prevention are far, so who’s going to get elected on a platform of diverting those funds?

Couldn’t 1,000 observational studies give us good ideas as to which treatments are harmful or wasteful at the margin? And which are beneficial (I’m sure some are)? We’d still have a picture of how useful medicine is at the margin, but we’d also get an idea of which treatments were helpful and which ones weren’t.

Anyway, when my mom had a glioblastoma, she had two surgeries, radiation treatment and chemotherapy. She died within a year of the initial diagnosis. Interestingly, her GP told her, after the first surgery (which was indicated to confirm the type of brain tumor), not to undergo further treatment, as it would be painful and offer no meaningful benefit. However, the oncologists were much more bullish on the effects of treatment. Had we known then what we know now, we might have foregone treatment, but we deferred to the experts.

Clearly, in this case, considerable extra expense had no marginal benefit.

As a practical matter, who would volunteer to enroll in the study? Today, I figure lots of people would sign up for a 50% chance at free medicine. But consider those who land in the arm where they have to pay almost everything out of pocket. In 2014, they can drop out and buy subsidized insurance instead. Rationally, anyone who expected to save money that way would do so. Those who remain would be healthier than average, skewing the results
.

That raised a strange question: does Spriteless’ anecdote argue against Robin’s claim, or in favour of it?

The problem is that the naive reading of “medicine is on average is near useless or harmful on the margin;” is that the margin is the homeopathy zone. The treatments do nothing and only money is at stake. That is not actually what Robin is saying. Useless on average covers both useless in every case and a balance of kill and cure.

Spriteless’ anecdote offers us an image of the typical medical procedure as a reasonably priced surgery that is directly life saving. If that were the end of the story it would be easy to show that medical expenditures produced a large impact on mortality. It’s not. So what is the rest of the story?

Accepting Robin’s judgement that it is hard to demonstrate the marginal benefit of medicine in the aggregate figures, the implications of Spriteless’ anecdote are perhaps inverted. If I’m persuaded that reasonably priced surgeries that are directly life saving are common place, then my heart sinks, for the implication is that the average is coming from a balancing factor of common place medical disaster. And Robin’s point becomes about lives as well as money; there are many lives to be saved by cutting back on killer surgery.