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Purpose and Sponsorship

NGC is a Web site intended to make evidence-based clinical practice guidelines, related summaries, and companion materials widely available to health care professionals. NGC is an initiative of the Agency for Healthcare Research and Quality (AHRQ), U.S. Department of Health and Human Services, and was created by AHRQ in partnership with the American Medical Association and the American Association of Health Plans (now America's Health Insurance Plans [AHIP]). AHRQ sponsors and maintains the NGC pursuant to statutory mandates (1) to support research designed to improve the quality of health care, reduce its cost, and broaden access to essential services and (2) to develop and disseminate evidence-based information to increase the scientific knowledge needed to enhance patient and clinical decision-making, improve health care quality, and promote efficiency in the organization of public and private systems of health care delivery. The guidelines and some of the related materials on this site are the products of named organizations that are solely responsible for their content. Objective summaries and factual comparisons of the guidelines at this site are prepared by AHRQ's contractor, ECRI Institute, in consultation with the responsible organizations that prepared the respective guidelines. The authors and publishers of every document at this site are identified at the end of each document.

Intended Audience

The informational offerings presented on this site are intended primarily for the following audiences:

  • Physicians, nurses, and other health care professionals and provider organizations
  • Health plans, health systems, health care organizations, hospitals, and integrated health care delivery systems
  • Medical specialty and professional societies
  • Researchers
  • Federal, State, and local government health care policymakers and specialists

Other Audiences Including Patients

If you are a patient and are accessing this site, you should understand that the information presented is intended and designed for the use of the expert audiences previously identified. You should seek assistance from a health care professional in interpreting these materials and applying them in individual cases.

Definition and Selection of Evidence-based Guidelines and Related Materials

The NGC database contains evidence-based clinical practice guidelines as defined by the Institute of Medicine (IOM):

Clinical practice guidelines are statements that include recommendations intended to optimize patient care that are informed by a systematic review of evidence and an assessment of the benefits and harms of alternative care options.

These guidelines are not fixed protocols that must be followed, but are intended for health care professionals and providers to consider. While they identify and describe generally recommended courses of intervention, they are not presented as a substitute for the advice of a physician or other knowledgeable health care professional or provider. Individual patients may require different treatments from those specified in a given guideline. Guidelines are not entirely inclusive or exclusive of all methods of reasonable care that can obtain/produce the same results. While guidelines can be written that take into account variations in clinical settings, resources, or common patient characteristics, they cannot address the unique needs of each patient nor the combination of resources available to a particular community or health care professional or provider. Deviations from clinical practice guidelines may be justified by individual circumstances. Thus, guidelines must be applied based on individual patient needs using professional judgment.

Although AHRQ and its contractor, ECRI Institute, set minimum inclusion criteria, NGC does not make judgments regarding the comparative quality of information on the site. NGC verifies that each guideline meets the established minimum criteria for inclusion, but does not verify or evaluate the accuracy or appropriateness of the individual guideline content.


NGC Disclaimer

NGC does not develop, produce, approve, or endorse the guidelines represented on this site.

All guidelines summarized by NGC and hosted on our site are produced under the auspices of medical specialty societies, relevant professional associations, public or private organizations, other government agencies, health care organizations or plans, and similar entities.

Guidelines represented on the NGC Web site are submitted by guideline developers, and are screened solely to determine that they meet the NGC Inclusion Criteria.

NGC, AHRQ, and its contractor, ECRI Institute, make no warranties concerning the content or clinical efficacy or effectiveness of the clinical practice guidelines and related materials represented on this site. Moreover, the views and opinions of developers or authors of guidelines represented on this site do not necessarily state or reflect those of NGC, AHRQ, or its contractor, ECRI Institute, and inclusion of guidelines in NGC may not be used for advertising or commercial endorsement purposes.

Readers with questions regarding guideline content are directed to contact the guideline developer.

Liability Disclaimer

With respect to the information available from this site, neither AHRQ nor its contractor, ECRI Institute, nor any of their employees, makes any warranty, express or implied, including the warranties of merchantability and fitness for a particular purpose, or assume any legal liability or responsibility for the accuracy, completeness, clinical efficacy or value of any such information or any apparatus, product, or process described or referenced in NGC material or in material at other sites linked to NGC.

In addition, AHRQ and its contractor, ECRI Institute, cannot endorse, or appear to endorse, derivative or excerpted materials, and cannot be held liable for the content or use of adapted products that are incorporated on other Web sites. Any adaptations of these electronic documents and resources must include a disclaimer to this effect. Advertising or implied endorsement for any commercial products or services is strictly prohibited.

Endorsement Disclaimer

Reference on this Web site to any specific commercial products, process, service, manufacturer, company, or trademark does not constitute its endorsement or recommendation by AHRQ or its contractor, ECRI Institute. As an agency of the U.S. Government, AHRQ cannot endorse or appear to endorse any specific commercial products or services.

Permission to Reproduce Content

Permission and requirements regarding reproduction and downloading of respective documents and files are specific to each guideline and related documents in the NGC database. Please read carefully and comply with specific notices on downloading and reproduction contained within each document. Documents available from this site may be protected under U.S. and foreign copyright laws unless otherwise noted. Permission to reproduce or to disseminate further may be required.

Site Protection and Monitoring Notice

To assure the integrity of information on this site and to make it responsive to public needs and demand requirements, AHRQ will monitor system access against actions to disable these online services and against deliberate efforts to gain unauthorized access to restricted portions of the NGC Web site.

By accessing this site you are consenting to system monitoring for law enforcement and other purposes. AHRQ does not restrict linked sites from obtaining information about visitors to their sites.

Links to Other Sites

Our Web site has links to Federal agencies, guideline developing and submitting organizations, and selected links to other Web resources. The Privacy Policy Notice does not apply to those other sites. Once you link to another site, you are subject to the privacy policy of that site.

NGC is not responsible for the availability or content of these external sites, nor does NGC endorse, warrant, or guarantee the products, services, or information described or offered at these other Internet sites. Users cannot assume that the external sites will abide by the same Privacy Policy to which NGC adheres.

Page Last Reviewed or Updated: July 15, 2016