title: A guide to GRADE guidelines for the readers of JTH.
abstract: More than 70 organizations worldwide have adopted the GRADE methodology for guideline development. The ninth iteration of the American Collage of Chest Physicians guidelines (AT9) adopted structural and policy changes that resulted in a greater adherence to GRADE guidance than previous iterations. The most important of these changes include minimizing the impact of financial and intellectual conflict of interest, increasing the rigor of evidence evaluation, acknowledging uncertainty in estimates of typical values and preferences, and awareness of the large variability in values and preferences. One of the consequences of the greater adherence to GRADE methodology is an increase in weak vs. strong recommendations in AT9. The result of the GRADE process highlights the desirability of higher-quality evidence both regarding the outcomes of alternative management strategies and regarding the distribution of values and preferences in patients considering those alternatives. It also encourages shared decision making in encounters between physicians and patients. Although some physicians might find the uncertainty underlying medical practice discouraging or unsettling, relative to denying or obscuring the uncertainty, acknowledging and addressing the uncertainty will lead to more credible, realistic, and useful recommendations.
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
authors.forename: G
authors.initials: G
authors.lastname: Guyatt
authors.forename: J W
authors.initials: JW
authors.lastname: Eikelboom
authors.forename: E A
authors.initials: EA
authors.lastname: Akl
authors.forename: M
authors.initials: M
authors.lastname: Crowther
authors.forename: D
authors.initials: D
authors.lastname: Gutterman
authors.forename: S R
authors.initials: SR
authors.lastname: Kahn
authors.forename: H
authors.initials: H
authors.lastname: Schunemann
authors.forename: J
authors.initials: J
authors.lastname: Hirsh
mesh_terms: D001241:Aspirin / Q000627:therapeutic use; D003657:Decision Making; D019317:Evidence-Based Medicine / Q000379:methods; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D019983:Guideline Adherence; D006405:Hematology / Q000592:standards*; D006801:Humans; D007391:International Cooperation; D017410:Practice Guidelines as Topic; D012196:Review Literature as Topic; D012955:Societies, Medical; D016896:Treatment Outcome; D014481:United States
chemical_list: D005343:Fibrinolytic Agents; D001241:Aspirin
keywords: antithrombotic agents; aspirin; conflict of interest; evidence-based medicine; guidelines