Determining the criteria for the selection of priority areas required making choices and value judgments based on available evidence while taking into account principles of improving population health and effecting social justice. Several key questions had to be addressed. Should the emphasis be on conditions for which the potential for improvement through systems change is greatest, or those for which the clinical burden and quality deficits are greatest? What evidence is available to inform these decisions, and what are the gaps in that evidence? And what are the trade-offs between choosing priority areas for which the benefits are more modest but predictable and those for which the benefits are more uncertain but potentially greater?
The core issue underlying these questions— how best to allocate limited resources—is a question with which policy makers in the public and private sectors must grapple every day. The Institute of Medicine (IOM) has previously addressed priority setting in three other contexts—technology assessment (Institute of Medicine, 1992), clinical practice guidelines (Institute of Medicine, 1995), and research funding (Institute of Medicine, 1998a). However, this committee’s charge was distinct from these previous efforts: to identify a set of conditions for which quality improvement within the health system could have the most benefit. Thus for candidate priority areas, the committee needed to examine:
Not only the clinical burden of illness, but also the extent of preventable burden attributable to the failure to deliver best-practice care.
Not just the degree to which the current system is broken, but also the extent to which known health care system changes could close gaps between best practice and usual care.
Not only how to improve clinical care for the population as a whole, but also how to address unacceptable disparities in health care.
Not only how to improve clinical care for individual conditions, but also how to identify an initial set of conditions for which improving care could be broadly transformative across the U.S. health care system.
The committee considered three general issues when discussing potential selection criteria. First, to what degree could existing evidence be a guide in assessing candidate priority areas according to the criteria? Second, how broadly should individual priority areas be defined? And finally, where should the line be drawn between the health care system and the rest of society in understanding the potential causes and consequences of the quality gaps in each area?
It has been about 10 years since the term “evidence-based medicine” entered the medical literature (Guyatt, 1991), and since that time the term has become nearly ubiquitous in the vocabulary of clinicians, managers, and researchers. Evidence-based medicine involves the use of clinical research data to develop guidelines or best-practice standards for care. Just as evidence-based medicine can serve as a goal to guide clinical practice, the committee sought to ground its decisions, wherever possible, in quantitative data from the peer-reviewed literature and from nationally representative surveys.
While it is appealing to seek to apply the principles of evidence-based medicine to priority setting and quality improvement, a number of factors make doing so challenging for health systems (Walshe and Rundall, 2001). First, valid and widely applied measures do not exist for some exceptionally important concerns, such as functional capacity. As a result, available sources of data may not include essential gauges of the impact of some conditions in causing a loss of function or