Several interrelated strategies involving physician leadership and participation have been proposed to contain health care costs while preserving or improving quality. These include programs targeting the 10% of the population that incurs 70% of health care expenditures, disease management programs to prevent costly complications of chronic conditions, efforts to reduce medical errors, the strengthening of primary care practice, decision support tools to avoid inappropriate services, and improved diffusion of technology assessment. An example of a cost-reducing, quality-enhancing program is post-hospital nurse monitoring and intervention for patients at high risk for repeated hospitalization for congestive heart failure. Disease management programs that target groups with a chronic condition rather than focusing efforts on high-utilizing individuals may be effective in improving quality but may not reduce costs. Error reduction has great potential to improve quality while reducing costs, although the probable cost reduction is a small portion of national health care expenditures. Access to primary care has been shown to correlate with reduced hospital use while preserving quality. Inappropriate care and overuse of new technologies can be reduced through shared decision-making between well-informed physicians and patients. Physicians have a central role to play in fostering these quality-enhancing strategies that can help to slow the growth of health care expenditures.

Reports of clinical trials usually emphasize benefits and give less attention to harms.

The Evidence-based Practice Center (EPC) program within the Agency for Healthcare Research and Quality (AHRQ) provides detailed evidence reports for partner organizations that they can translate into activities that improve patient care. A review of these dissemination activities provides a rich opportunity to understand how to create more successful linkages between best evidence and best practice. On the basis of interviews with EPC directors, AHRQ staff, and representatives of public and private users of EPC reports, we summarize the variety of efforts to disseminate the work of the EPCs. We also identify a case example of a successful dissemination of an EPC report. Experience to date reinforces the importance of creating close ties between researchers and the policymakers, clinicians, and other decision makers who use EPC evidence reports; developing a conceptual framework to guide the process; and establishing the resource foundation for the entire effort.

Randomized, controlled trials (RCTs) are firmly established as the standard for determining which medical treatments are effective. In some areas of health care, however, among them surgery, public health, and the organization of health care delivery, most evidence addressing the effectiveness of clinical or policy interventions rests on nonrandomized studies. We examine the use of study designs other than RCTs in Evidence-based Practice Center reports addressing questions of the effectiveness of treatment interventions. These reports offer the opportunity to examine the approaches used and the challenges faced by reviewers when nonrandomized studies are included and their quality assessed. We then offer recommendations for using these studies in systematic reviews of treatment interventions.

The authors discuss 3 challenges in conducting and interpreting any systematic review that are particularly relevant for systematic reviews of therapeutic devices or surgical procedures: 1) inclusion or exclusion of grey literature, 2) the role of nonrandomized studies, and 3) issues in applying the results to clinical care that are unique to the surgical and therapeutic device literature. The authors also discuss empirical evidence related to these topics and illustrate how reviewers in the Agency for Healthcare Research and Quality's Evidence-based Practice Center program have dealt with these challenges in developing evidence reports for decision makers and clinicians about therapeutic devices or surgical procedures.

An evidence synthesis of a medical intervention should assess the balance of benefits and harms. Investigators performing systematic reviews of harms face challenges in finding data, rating the quality of harms reporting, and synthesizing and displaying data from different sources. Systematic reviews of harms often rely primarily on published clinical trials. Identifying important harms of treatment and quantifying the risk associated with them, however, often require a broader range of data sources, including unpublished trials, observational studies, and unpublished information on published trials submitted to the U.S. Food and Drug Administration. Each source of data has some potential for yielding important information. Criteria for judging the quality of harms assessment and reporting are still in their early stages of development. Investigators conducting systematic reviews of harms should consider empirically validating the criteria they use to judge the validity of studies reporting harms. Synthesizing harms data from different sources requires careful consideration of internal validity, applicability, and sources of heterogeneity. This article highlights examples of approaches to methodologic issues associated with performing systematic reviews of harms from 96 Evidence-based Practice Center evidence reports.

Educators have recognized the need to apply evidence-based approaches to medical training. To do so, medical educators must have access to reliable evidence on the impact of educational interventions. This paper describes 5 methodologic challenges to performing systematic reviews of educational interventions for health care professionals: finding reports of medical education interventions, assessing quality of study designs, assessing the scope of interventions, assessing the evaluation of interventions, and synthesizing the results of educational interventions. We offer suggestions for addressing these challenges and make recommendations for reporting, reviewing, and appraising interventions in medical education.

Economic analyses can provide valuable information for health care decision makers. Systematic reviews of economic analyses can integrate information from multiple studies and provide important insights by systematically examining how differences between models lead to different results. We use our experience in developing and implementing systematic reviews of economic analyses for the U.S. Preventive Services T ask Force, particularly our systematic review of the cost-effectiveness of colorectal cancer screening, to illustrate key methodologic challenges and suggest a framework for other researchers in this area.

Increasingly, consumers, clinicians, regulatory bodies, and insurers are using systematic reviews of drug interventions to select treatments and set policies. Although a systematic review cannot provide all the information a clinician needs to make an informed choice for therapy, it can help decision makers distinguish what claims about effectiveness are based on evidence, identify critical information gaps, describe features of the evidence that limit applicability in practice, and address whether drug effectiveness differs for particular subgroups of patients. To improve the relevance and validity of reviews of drug therapies, reviewers need to delineate clinically important subgroups, specific aims of therapy, and most important outcomes. They may need to find unpublished trials, studies other than direct comparator (head-to-head) trials, and additional details of published trials from pharmaceutical manufacturers and regulatory agencies. In this paper, we address ways to formulate questions relevant to specific clinical therapeutic aims; discuss types of studies to include in drug efficacy and effectiveness reviews and how to find them; and describe ways to assess applicability of studies to actual practice.

Some important health policy topics, such as those related to the delivery, organization, and financing of health care, present substantial challenges to established methods for evidence synthesis. For example, such reviews may ask: What is the effect of for-profit versus not-for-profit delivery of care on patient outcomes? Or, which strategies are the most effective for promoting preventive care? This paper describes innovative methods for synthesizing evidence related to the delivery, organization, and financing of health care. We found 13 systematic reviews on these topics that described novel methodologic approaches. Several of these syntheses used 3 approaches: conceptual frameworks to inform problem formulation, systematic searches that included nontraditional literature sources, and hybrid synthesis methods that included simulations to address key gaps in the literature. As the primary literature on these topics expands, so will opportunities to develop additional novel methods for performing high-quality comprehensive syntheses.

Diagnostic tests are critical components of effective health care. They help determine treatments that are most beneficial for a given patient. Their assessment is a complex process that includes such challenges as a dearth of studies that evaluate clinical outcomes and lack of data on use of the test in realistic clinical settings. The methodologic quality of studies of diagnostic tests also lags behind the quality of studies of therapeutic interventions. Statistical methods to combine diagnostic accuracy data are more complex and not as well developed, leading to difficulties in the interpretation of results. The Agency for Healthcare Research and Quality Technology Assessment Program has adopted a 6-level framework for evaluating diagnostic technologies. The model emphasizes the need for systematic reviews of diagnostic test studies to go beyond the assessment of technical feasibility and accuracy to examine the impact of the test on health outcomes. In this paper, we use examples from 3 Evidence-based Practice Center reports to illustrate 3 challenges reviewers may face when reviewing diagnostic test literature: finding relevant studies, assessing methodologic quality of diagnostic accuracy studies, and synthesizing studies that evaluate tests in different patient populations or use different outcomes.

The use of complementary and alternative medicine (CAM) continues to grow in the United States. The Agency for Healthcare Research and Quality has devoted a substantial proportion of the Evidence-based Practice Center (EPC) program to systematic reviews of CAM. Such syntheses present different challenges from those conducted on western medicine topics, and in many ways are more difficult. We discuss 3 challenges: identifying evidence about CAM, assessing the quality of individual studies, and addressing rare serious adverse events. We use illustrations from EPC evidence reports to show readers approaches to the 3 areas and then present specific recommendations for each issue.

To provide decision makers with the best available evidence, the Agency for Healthcare Research and Quality established a network of Evidence-based Practice Centers across North America. The centers perform systematic reviews on important questions posed by partner organizations about clinical, organizational, and policy interventions in healthcare. The Agency works closely with partners and other decision maker s to help translate that evidence into practice or policy. In this paper, we review important lessons we have learned over the past 7 years about how to increase the efficiency and impact of systematic reviews. Lessons concern selecting the right topics and scope, working effectively with partners, and balancing consistency and flexibility in methods. We examine continuing evolutions of the program and the impact of planned work on comparative effectiveness performed as part of the Medicare Modernization Act of 2003.

One commonly held explanation for high and rising health care costs in the United States points to the market power of health care providers. This third article of a 4-part series examines how the prices and quantities of health care services interact to influence health care expenditures. The article also reviews cost-containment strategies that are designed to reduce prices and quantities of services. One major difference between the costs of care in the United States and those in other developed nations is the price per unit of care--physician fees, payments per hospital day, and pharmaceutical prices. Greater quantities of high-priced innovative technologies in the United States also contribute to higher expenditures in the United States compared with other nations. During the 1990s, payers were partially successful in slowing cost growth by reducing the prices of physician and hospital payments, but more recently, hospitals increased their market power by consolidation and could demand higher prices. Quantities and costs of services for Medicare beneficiaries vary markedly among geographic regions, with research showing an association between health care costs and the supply of hospital beds and specialist physicians. These findings suggest that limiting the supply of resources may reduce the quantity, and thereby the costs, of health services. Shifting the financial risk of health care costs from insurers to providers, as has been done with the Medicare diagnosis-related-group payment and capitation reimbursement, can also be effective in containing costs.

Bacterial infections are a major cause of illness and death in patients who are neutropenic after chemotherapy treatment for cancer. Trials have shown the efficacy of antibiotic prophylaxis in decreasing the incidence of bacterial infections but not in reducing mortality rates.

Technologic innovation, in combination with weak cost-containment measures, is a major factor in high and rising health care costs. Evidence suggests that improved health care technologies generally increase rather than reduce health care expenditures. Greater availability of such technologies as magnetic resonance imaging, computed tomography, coronary artery bypass graft, angioplasty, cardiac and neonatal intensive care units, positron emission tomography, and radiation oncology facilities is associated with greater per capita use and higher spending on these services. Because the spread of new technologies is relatively unrestrained in the United States, many of these technologies are used to a greater extent than in other nations, and the United States thereby incurs higher health care costs. Nations with a greater degree of health system integration have relied on expenditure controls and global budgets to control costs. Although diffusion of technology takes place more slowly in more tightly budgeted systems, the use of innovative technologies in those systems tends to catch up over time.

Although thyroid nodules are common, few are malignant and require surgical treatment. A systematic approach to their evaluation is important to avoid unnecessary surgery. Fine-needle aspiration biopsy has resulted in substantial improvements in diagnostic accuracy, cost reductions, and higher malignancy yield at time of surgery. The preferred approach when repeated fine-needle aspiration biopsy fails to yield an adequate specimen remains a challenge. Management of patients with nodules "suspicious for follicular neoplasm" is difficult, since only 15% to 20% of such lesions have been shown to be malignant. Immunohistochemical markers, such as galectin-3 and human bone marrow endothelial cell (HBME-1), have shown promise in preliminary studies. Routine calcitonin measurement in patients with thyroid nodules has been advocated for early detection of medullary thyroid cancer. However, the low frequency of this cancer, coupled with the high cost associated with case detection, has resulted in a lack of general acceptance of this recommendation.

Testing of urine samples is noninvasive and could overcome several barriers to screening for chlamydial and gonococcal infections, but most test samples are obtained directly from the cervix or urethra.