Medical necessity under weak evidence and little or perverse regulatory gatekeeping

Medical necessity (claiming that a medical intervention or care is – at minimum – reasonable, appropriate and acceptable) depends on empirical evidence and on the interpretation of that evidence. Evidence and its interpretation define the standard of care. This commentary argues that both the evidence base and its interpretation are currently weak gatekeepers. Empirical meta-research suggests that very few medical interventions have high quality evidence in support of their effectiveness and very few of them also have relatively thorough assessments of their potential harms. Therefore, evidence on the risk-benefit ratios carries almost always very large uncertainty. Arbitration about medical necessity is thus left to the interpretation process. Professional guidelines are notoriously unreliable and biased in this regard. Regulatory approval ends up being the key arbitrator, but over the years the regulatory process has been subverted. Regulatory approval currently does not mean that an intervention has a favourable risk-benefit ratio, but simply that it can be marketed, sold and made profit from. The process leads to a tragedy of commons where the final victim is society at large: medical necessity is invoked as an alibi for medicine to absorb societal resources.