The ever-increasing volume of evidence makes it difficult for clinicians to maintain a working knowledge of new clinical information. Even after identifying relevant information for a given condition, clinicians and their patients still must ensure that the information is of high quality. Clinicians must consider the quality of a study to minimize the possibility that the evidence will be contradicted by later studies, and ensure that the research is free of conflicts of interest and applies to their particular patient’s clinical circumstances (Ioannidis, 2005; Prasad et al., 2011).

Uneven Diffusion of Knowledge

Although the supply of knowledge is increasing, there are lags in the time it takes to translate promising evidence into clinical practice. It is estimated that the results of a landmark study will take 15-16 years to be widely implemented following the study’s publication (Balas and Boren, 2000). For example, it took 13 years for most experts to recommend thrombolytic drugs for heart attack treatment after their first positive clinical trial (Antman et al., 1992). Similarly, the results of major clinical trials often are not implemented in regular clinical practice, as was the case for the Occluded Artery Trial (OAT) on the timing of coronary angioplasty after heart attack (Deyell et al., 2011; Redberg, 2011), the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) on effective treatments for high blood pressure (Avorn, 2010; Stafford et al., 2010), and the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) study on coronary angioplasty versus medical therapy (Borden et al., 2011). As a result of this slow diffusion of knowledge and other factors, Americans receive only half of the preventive, acute, and chronic care recommended by clinical guidelines (McGlynn et al., 2003) and approximately 60 percent of recommended pharmaceutical treatments (Shrank et al., 2006).

Implications of Advances in Genetics

The accelerating pace of research has led to striking prospects for individualized diagnoses and treatments. Although the potential is still largely unrealized, ongoing developments offer promise to accelerate this progress. For example, the cost of sequencing the whole genome has decreased from $2.7 billion, the cost when the first human genome was sequenced, to $10,000 in 2010 and may fall to as little as $1,000 in the foreseeable future (Samani et al., 2010). Between 2005 and 2008, more than 100 genetic variants associated with nearly 40 complex diseases and traits were identified and replicated using genomewide scans, and in 2008, genetic tests for more than 1,200 clinical conditions were available (Genetics and Public Policy



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