This week’s BMJ is a theme-based issue on Evidence-Based Medicine. It contains the expected articles on how to judge whether or not EBM is living up to its promise, how best to implement it, and so on. There is one aspect of EBM, however, that is not addressed: its effect on the drug and device industries.
An implicit subtext of the evidence-based movement is that it helps counter the millions of dollars of industry propaganda and hype that wash over us every year. And EBM does, indeed, provide tools to judge drugs and interventions more objectively than we think the industry would like us to. But the drug and device industries have evolved along with (or ahead of) their customers.
Pharmaceutical companies have responded to EBM by carefully designing trials destined to apply to as wide a population as possible, while still obtaining (p<0.05) benefit. Then, armies of drug reps sally forth armed with reprints, while researchers are sent out to spread the gospel of statistical significance. EBM has made us particularly avid of hard data (while relegating clinical significance to a somewhat subordinate role). This emphasis on statistically significant data has been digested by industry and is now used to sell drugs and devices.
Evidence is good. Evidence-based methodologies are better. But they aren’t magic bullets. And EBM is a tool whose use is not restricted to pure and virtuous clinicians. Caveat lector.