Whither preventive medicine?

To the extent that Gabe Slowey and David Rapoport hold globally negative views on personal preventive measures and because Nicholas Forbath assigns me a nihilistic view of them, I disagree with all 3 of these correspondents.

During my clinical and health policy years I advocated and applied a wide array of personal preventive manoeuvres because I was dedicated, not to global conclusions about the value of preventive medicine, but to methods for generating level 1 evidence1 as to whether its individual elements did more good than harm (by level 1 evidence I mean either systematic reviews of randomized trials or “all-or-none” evidence by which, for a universally fatal condition, an intervention was followed by survival or a less frequent adverse outcome was completely eliminated by the intervention). On that basis I advocated and practised the vigorous detection and treatment of certain levels of symptomless elevated blood pressure,2 never ordered testing of prostate-specific antigen in a symptomless man, and changed my practice and teaching about treating hypercholesterolemia from a negative to a positive stance when the accumulating evidence from randomized trials of statin drugs showed that they did more good than harm.

In response to Mark Taylor, because the absence of proof is not the proof of absence, folks like me don't advocate abandoning established practices just because they haven't been tested in randomized controlled trials. Moreover, seat belt use satisfied the second criterion for level 1 evidence as soon as users began to survive auto crashes that were previously uniformly fatal. Importantly, however, when this same criterion is applied to another auto safety tradition, school-based drivers' education, the level 1 evidence shows that this intervention doesn't create better drivers, only younger ones, and its net effect appears to be harmful.3