Evidence-based medicine aims to provide clinicians and patients with choices about the most effective care based on the best available research evidence. To patients this is a natural expectation. To clinicians this is a near impossible dream. The US report Bridging the quality chasm has documented and drawn attention to the gap between what we know and what we do. The report identified types of quality problems—overuse, underuse, and misuse. It suggested: “The burden of harm conveyed by the collective impact of all of our health care quality problems is staggering.” While attention has focused on misuse (or error), a larger portion of the preventable burden is likely to be the evidence-practice gaps of underuse and overuse.
Research that should change practice is often ignored for years—for example, crystalloid (rather than colloid) for shock, supine position after lumbar puncture, bed rest for any medical condition, and appropriate use of anticoagulants and aspirin among patients with atrial fibrillation. Antman et al documented the substantial delays between cardiovascular trial results and textbook recommendations. However, even when best practices are well known they are often poorly implemented: national surveys show that the majority of hypertensive patients are undetected, untreated, or inadequately controlled, which has led to the current interest in knowledge translation.