About Guidelines

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

Guidelines FAQ

Q. What is the difference between a practice guideline and a quality measure?
A. Clinical Practice Guidelines are documents that include recommendations intended to optimize patient care that are based on an evidence-based systematic review. Quality measures are math equations to help understand how often health care services are consistent with current medical knowledge. Guideline recommendations form the denominator and numerator statements of quality measures.

Q. When do you update guidelines?
A. An update is considered when there is new published evidence that significantly changes either the conclusions or the recommendations in a guideline. Guidelines and case definitions are assessed at least every three years to determine whether new literature has been published that would warrant an update. If the Guideline Development, Dissemination, and Implementation (GDDI) Subcommittee is aware of new evidence that may change conclusions or recommendations in the guideline prior to the next scheduled triennial review, the Subcommittee will review earlier.

Q. Do you collaborate with other guideline developers?
A. Medical associations and organizations regularly work together on medical practice guidelines when multiple groups or clinician specialties are involved with the treatment of a specific disease. There are two levels of collaboration:

  • Full collaboration: The development panel reflects equal representation from the collaborating societies. The societies involved sign a formal letter of agreement outlining terms of copyright ownership, simultaneous publication, division of costs before project initiation, and the method to be used.
  • Invited participation: AAN staff works with the societies to obtain a nominee. This individual serves as the official representative from the organization, providing updates to the organization’s board of directors. The organization has the opportunity to review and comment on the guideline during public comment periods and to endorse the guideline before publication.


Additionally, the AAN has several ways of endorsing or affirming the value of guidelines developed by other organizations. For more information, review the AAN endorsement policy.

Q. How do you choose what guidelines to develop?
A. Guideline projects can are either updates to existing guideline that have become out of date, or are new projects. AAN members and others are welcome to submit topic nominations at any time. All topic nominations are reviewed by the Guideline Development, Dissemination, and Implementation (GDDI) Subcommittee. The Subcommittee reviews and votes on nominated topics quarterly using a ranking tool known as the Topic Nomination Priority Score (TNPS). The following criteria are taken into account:

  • Relevance to neurologists
  • Disease prevalence
  • Degree of practice variation or controversy
  • Project feasibility (amount of evidence, AAN and GDDI resources, whether collaboration with one or more external societies is required)
  • Impact on patient care and outcomes


Not all topics are accepted for development. In addition, the GDDI limits the existing topic list to 25 topics awaiting development at any one time.

Q. What information/studies will be considered and included in the guidelines?
A. Authors review the available scientific studies that 1) meet the inclusion criteria and 2) address the clinical question will be conducted and will serve as the basis for the development of each guideline. Inclusion criteria and questions are set before the literature search begins. In addition, unpublished literature (also known as grey literature), such as supplements, book chapters, and studies that are unpublished or are not included in bibliographic retrieval systems, is included as well to reduce publication bias.

Q. How is the level of evidence of each study determined?
A. For AAN guidelines, the risk of bias in studies is measured using a four-tiered classification scheme. In this scheme, studies rated Class I are judged to have a low risk of bias; Class II, a moderate risk of bias; Class III, a moderately high risk of bias; and Class IV, a very high risk of bias. The classification rating is also known as the level of evidence.

Q. What is GRADE?
A. GRADE stands for “Grading of Recommendations Assessment, Development and Evaluation.”
GRADE is a transparent approach to grading the quality of evidence and strength of recommendations. The methodology is designed to help clinicians understand the strength of the science backing treatment recommendations, minimizing bias and aiding them in their interpretation.

Q. Who is on guideline development panels and how were they chosen?
A. Panels include members of the Guideline Development, Dissemination, and Implementation Subcommittee, an evidence-based medicine methodologist, neurologist subject matter experts, non-neurologists subject matter experts, representatives from physician and patient organizations, and patient representatives. The Subcommittee leadership reviews and approves all panel members. The lead author and over half of the members of the development panel cannot have conflicts of interest. 

Steps of the AAN Evidence-based Guideline Development Process 

1 Select topic

  GDDI Subcommittee reviews topics submitted by committee members, AAN members, AAN sections, and others. Topics are prioritized by board-approved criteria (see FAQ)

2 Form development panel Panel members include Subcommittee members, a methodology expert, neurologist subject matter experts, organization representatives, and patient repressentatives.  All panel members must disclose all potential conflicts of interest. The AAN requires the lead author  and over half of the panel members to have no conflicts of interest related to the guideline topic. 
3 Develop clinical questions and protocol Each clinical question must have the following four elements: Population, Intervention, Co-Intervention, and Outcome. Questions drive the research and are included in the guideline protocol. The questions should address an area of quality concern, controversy, confusion, or practice variation.
4 Post protocol for public comment The protocol is a document that includes the clinical questions and the plan for the research strategy. The AAN posts the protocol on the AAN website for a 30-day public comment period to get feedback from members, organizations, and others affected by the disease to make sure the right questions are being asked. 
5 Review and analyze evidence 

A literature search is performed by a medical librarian, and then studies are reviewed by members of the development panel to determine if they meet inclusion criteria. Each study is reviewed by two independent reviewers.

Developers then create an evidence table and  populate with the essential characteristics of the included studies. Risk of bias is measured for each study using a four-tiered classification scheme.

A modified version of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) process is used to determine  whether the developer's confidence in the evidence is sufficient to support practice recommendations.

6 Synthesize  evidence and develop conclusions Data from the included studies is synthesized into conclusions. Conclusions are succinct statements that summarize the evidence

in answer to a specific clinical question. Conclusions inform recommendations. 

7 Develop recommendation statements  Actionable practice recommendations are based on evidence, and also consider the following elements (see FAQ or Development Manual for full list): patient preferences, cost, and value of benefit relative to the risk. 


8 Post draft guideline  for public comment The AAN posts the draft guideline on the AAN website for a 30-day public comment period to get feedback from members, organizations, and others affected by the disease, on the comprehensiveness and clarity of the document. 
9 Journal peer-review  The Neurology® journal solicits reviewers from its network to review and comment on the manuscript.
10 AAN approvals After public comment, the draft guideline must receive approval from the AAN Guideline Subcommittee, the AAN Practice Committee, and the AAN Institute Board of Directors before publishing 
11 Develop derivative products AAN guideline staff may develop tools for clinical and patient audiences, including the following: slide presentation, clinician summary, patient summary, guideline or case definition for clinicians, and algorithms.
12 Publish in Neurology and disseminate Guidelines are published in the AAN's journal, Neurology, and posted on the AAN website. Announcements are published in AANnews® and AANe-news, and guidelines are submitted to the National Guideline Clearinghouse. AAN communications staff may launch a media publicity campaign, including tactics such as issuing a press release.
13 Review for currency At least every three years, published guidelines are reviewed by the AAN Guideline Subcommittee for currency. Reviewed guidelines are reaffirmed as current, updated, or retired. 

Topic Nomination

To submit an idea for a future guideline, complete the topic nomination form. All topics are reviewed by the Guideline Development, Dissemination, and Implementation Subcommittee. To ask questions or for more information, reach out to