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NGC Disclaimer

Purpose and Sponsorship

The National Guideline Clearinghouse™ (NGC) is an Internet Web site intended to make evidence-based clinical practice guidelines and related abstract, summary, and comparison 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. NGC was originally 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 operates 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 beginning of each document.

Intended Audience

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

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. You may find out about Web sites that contain information designed especially for patients by visiting the patient resources page.

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):

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 judgement.

Although AHRQ, AMA, and AHIP set minimum inclusion criteria which are published in the Federal Register and on this site, NGC partners do not make judgments regarding the comparative quality of information on the site. AHRQ verifies that each guideline meets the established minimum criteria for inclusion, but does not verify or evaluate accuracy of the individual guideline content. Guideline summaries provide users of the site with categories for comparing the guidelines in the database.


AHRQ and its contractor ECRI Institute, AMA, and AHIP make no warranties concerning the content or clinical efficacy of the clinical practice guidelines and related materials. Inclusion of any guideline in NGC does not constitute or imply an endorsement by AHRQ or its contractor ECRI Institute, AMA, or AHIP of the guidelines or of the sponsor or developer of any such guidelines, and guideline.gov does not host any advertising.

Any reference in NGC materials, or in material linked to NGC, to a specific commercial product, process, or service by trade name, trademark, or manufacturer, does not constitute or imply an endorsement, recommendation, or any favoritism by the United States Government or its contractor ECRI Institute, AMA, or AHIP. The views and opinions of authors in the documents on this site do not necessarily state or reflect those of the United States Government or its contractor ECRI Institute, AMA, or AHIP and shall not be used for advertising or product endorsement purposes.

With respect to the information available from this site, neither the United States Government or its contractor ECRI Institute, AMA, AHIP 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.

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 with 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.

1Institute of Medicine. (1990). Clinical Practice Guidelines: Directions for a New Program. M.J. Field and K.N. Lohr (eds.) Washington, DC: National Academy Press (page 39).

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 on-line services and against deliberate efforts to gain unauthorized access to restricted portions of NGC.

By accessing this site you are consenting to system monitoring for law enforcement and other purposes. AHRQ, AMA, and AHIP have not restricted linked sites from obtaining information about visitors to their sites.

National Guideline Clearinghouse™ (NGC) Privacy Policy Notice

Information Automatically Collected and Stored

When you browse through any Web site, read pages, or download information, certain information about your visit can be collected. NGC automatically collects and temporarily stores the following information about your visit, but this information does not identify you personally:

NGC uses this information for statistics on the traffic to our site, to find out about general user interest in various areas of our site, and to help us make our site more useful to visitors.

NGC tracks the keywords that are entered into our search engine and the browse terms used to measure interest in specific topics, but we do not monitor which terms a particular user enters.

Cookie Disclaimer - A "cookie" is information stored on your computer by a Web server and used to customize your web service in some way. NGC uses cookies to store information about your interactions that may be needed later to perform a function. Currently, the NGC Web site uses "cookies" to remember whether a user has viewed the NGC Disclaimer statement and to store information in the users' Guideline Collection. NGC does not use "cookie" information for any other purpose, nor does it make the information available to anyone else.

You can choose not to accept cookies and still use the NGC Web site. However, you will be unable to use the cookie-dependent features. Refer to the help information in your browser software for instructions on how to disable cookies.

No additional information is collected about your visit, and we do not record information about individual behavior or use of the site.

Personally Provided Information

You do not have to give us personal information to visit our Web site. If you choose to provide us with additional information about yourself through an e-mail message, form, survey, etc., we will only maintain the information as long as needed to respond to your question or to fulfill the stated purpose of the communication. The information provided is handled on a confidential basis. However, e-mail is not necessarily secure against interception. If your message is sensitive, you may prefer to send it by postal mail instead.


Except for authorized law enforcement investigations, NGC makes no attempt to identify individual users or usage patterns. We do not give, share, sell or transfer any personal information to a third party.

Intrusion Detection

For site security purposes and to ensure that this service remains available to all users, we employ software programs to monitor traffic to identify unauthorized attempts to upload or change information, or otherwise cause damage. Such attempts are strictly prohibited and may be punishable under the Computer Fraud and Abuse Act of 1986 and the National Information Infrastructure Protection Act.

Systems of Records

Electronically submitted information is maintained and destroyed according to the principles of the Federal Records Act and regulations and guidance from the National Archives and Records Administration, and in some cases may be subject to the Privacy Act. If information that you submit is to be used in a Privacy Act system of records, there will be a Privacy Act Notice provided.

Links to Other Sites

Our Web site has links to other Federal agencies. We also have selected links to other Web resources. The privacy policy described here does not necessarily apply to those other sites. Once you link to another site, you are subject to the privacy policy of that site.

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