Reversals of Established Medical Practices: Evidence to Abandon Ship

摘要: IDEALLY, GOOD MEDICAL PRACTICES ARE REPLACED BY BETter ones, based on robust comparative trials in which new interventions outperform older ones and establish standards of care. Often, however, established must be abandoned not because a better replacement has been identified but simply what was thought to beneficial not. In these cases, it becomes apparent that clinicians, encouraged by professional societies guidelines, have using medications, procedures, or preventive measures vain. For example, percutaneous coronary intervention performed for stable artery disease hormone therapy prescribed postmenopausal women cost billions dollars supported the existence entire specialties many years. Stable accounted 85% all stenting United States at time Clinical Outcomes Utilizing Revascularization Aggressive Drug Evaluation (COURAGE) trial. Large, well-designed randomized tested whether practices improved major patient outcomes revealed patients were being helped. Defenders therapies wrote rebuttals editorials fought their specialties, reality best could done abandon ship. How medical care are wrong? It is known. Medical practice evolved out centuries theorizing, personal experiences, bits evidence, expert consensus, diverse conflicts biases. Rigorous questioning long-established difficult. There thousands clinical trials, most deal with trivialities efforts buttress sales specific products. Given this conundrum, possible some subspecialties little evidence. Their disappearance probably would harm might help salvage derailed health budgets. However, unlikely specialists support testing constitute main source income. Instead, research community performs studies modest incremental value without even knowing basic appropriate. Rarely, investigators find courage test “truths” large, rigorous trials. When happens, empirical evidence suggests “medical reversals” may quite common. an evaluation 35 published journal 2009 practice, 16 (46%) reported results consistent current contradicted constituted reversal, another 3 (9%) inconclusive. Perhaps high-profile general journals more prone publish unusual less inclined defend specialized turf than specialty journals. selection filter favor reversal publications stronger favoring validation standard The mere generates interest never tested. high–impact factor journals, 39 mostcited 1990-2003 found significant benefit intervention, 9 (23%) effects those subsequent 19 (49%) replicated studies, 11 (28%) remained largely unchallenged, no large trial conducted same question. Many reversals involve conditions promoted over years primarily pathophysiological considerations. Often one exist, they clinically relevant biased. vertebroplasty—the injection polymethylmethacrylate cement into fractured bone—gained popularity early 2000s treatment osteoporotic fractures. Initial addressed pathophysiology therapy, delineated technical skills required optimally perform procedure, furthered discussion about benefits vertebroplasty. Claims strongly 2 included sham pro-