evidence on specific topics in clinical prevention that serve as the scientific basis for USPSTF recommendations. The USPSTF reviews the EPC report, estimates the magnitude of benefits and harms for each preventive service, reaches consensus about the net benefit for each preventive service, and issues a recommendation.

A number of organizations track and evaluate provider performance by measuring their actual clinical practices against the recommended practices (Table 2-4). To conduct this work, performance measurement groups first establish standards of care against which the performance of providers can be assessed. These are based on the available evidence and the guidelines issued by professional groups. In many cases, however, adequate guidelines are not available or are not evidence based, and this has been a significant barrier to the development of performance measures.

Although the U.S. system for the development, synthesis, and application of clinical evidence has expanded and improved over the past several decades, it continues to face significant challenges. Among these are the persistent gaps in the information available to decision makers, as well as the confusing manner in which the information is presented (e.g., different organizations use different coding schemes to represent similar concepts). Moreover, the quality of the information is often suspect because of a lack of transparency regarding the methods used to generate the information as well as conflict of interest concerns. In addition, inefficiencies in the current system that result from duplications of effort mean that fewer resources are available to fill the remaining information gaps. These concerns are detailed below.

Physicians now have access to a vast amount of relevant clinical information, but often this information is difficult to navigate and it may not address their specific concerns (Tunis, 2005). New tools, such as the Up-to-Date database and the American College of Physicians’ Physicians’ Information and Education Resource are bringing more information directly to physicians’ offices, but uncertainties about the quality and the applicability of the evidence remain.

The available information may not be suitable to the clinician’s needs for a number of reasons. For example, although the provider may want to