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Journal of Clinical Epidemiology | 2011

GRADE guidelines: 1. Introduction—GRADE evidence profiles and summary of findings tables

Gordon H. Guyatt; Andrew D Oxman; Elie A. Akl; Regina Kunz; Gunn Elisabeth Vist; Jan Brozek; Susan L. Norris; Yngve Falck-Ytter; Paul Glasziou; Hans deBeer; Roman Jaeschke; David Rind; Joerg J. Meerpohl; Philipp Dahm; Holger J. Schünemann

This article is the first of a series providing guidance for use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system of rating quality of evidence and grading strength of recommendations in systematic reviews, health technology assessments (HTAs), and clinical practice guidelines addressing alternative management options. The GRADE process begins with asking an explicit question, including specification of all important outcomes. After the evidence is collected and summarized, GRADE provides explicit criteria for rating the quality of evidence that include study design, risk of bias, imprecision, inconsistency, indirectness, and magnitude of effect. Recommendations are characterized as strong or weak (alternative terms conditional or discretionary) according to the quality of the supporting evidence and the balance between desirable and undesirable consequences of the alternative management options. GRADE suggests summarizing evidence in succinct, transparent, and informative summary of findings tables that show the quality of evidence and the magnitude of relative and absolute effects for each important outcome and/or as evidence profiles that provide, in addition, detailed information about the reason for the quality of evidence rating. Subsequent articles in this series will address GRADEs approach to formulating questions, assessing quality of evidence, and developing recommendations.


Journal of Clinical Epidemiology | 2011

GRADE guidelines: 9. Rating up the quality of evidence.

Gordon H. Guyatt; Andrew D Oxman; Shahnaz Sultan; Paul Glasziou; Elie A. Akl; Pablo Alonso-Coello; David Atkins; Regina Kunz; Jan Brozek; Victor M. Montori; Roman Jaeschke; David Rind; Philipp Dahm; Joerg J. Meerpohl; Gunn Elisabeth Vist; Elise Berliner; Susan L. Norris; Yngve Falck-Ytter; M. Hassan Murad; Holger J. Schünemann

The most common reason for rating up the quality of evidence is a large effect. GRADE suggests considering rating up quality of evidence one level when methodologically rigorous observational studies show at least a two-fold reduction or increase in risk, and rating up two levels for at least a five-fold reduction or increase in risk. Systematic review authors and guideline developers may also consider rating up quality of evidence when a dose-response gradient is present, and when all plausible confounders or biases would decrease an apparent treatment effect, or would create a spurious effect when results suggest no effect. Other considerations include the rapidity of the response, the underlying trajectory of the condition, and indirect evidence.


European Respiratory Journal | 2014

International ERS/ATS guidelines on definition, evaluation and treatment of severe asthma

Kian Fan Chung; Sally E. Wenzel; Jan Brozek; Andrew Bush; Mario Castro; Peter J. Sterk; Ian M. Adcock; Eric D. Bateman; Elisabeth H. Bel; Eugene R. Bleecker; Louis-Philippe Boulet; Christopher E. Brightling; Pascal Chanez; Sven-Erik Dahlén; Ratko Djukanovic; Urs Frey; Mina Gaga; Peter G. Gibson; Qutayba Hamid; Nizar N. Jajour; Thais Mauad; Ronald L. Sorkness; W. Gerald Teague

Severe or therapy-resistant asthma is increasingly recognised as a major unmet need. A Task Force, supported by the European Respiratory Society and American Thoracic Society, reviewed the definition and provided recommendations and guidelines on the evaluation and treatment of severe asthma in children and adults. A literature review was performed, followed by discussion by an expert committee according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach for development of specific clinical recommendations. When the diagnosis of asthma is confirmed and comorbidities addressed, severe asthma is defined as asthma that requires treatment with high dose inhaled corticosteroids plus a second controller and/or systemic corticosteroids to prevent it from becoming “uncontrolled” or that remains “uncontrolled” despite this therapy. Severe asthma is a heterogeneous condition consisting of phenotypes such as eosinophilic asthma. Specific recommendations on the use of sputum eosinophil count and exhaled nitric oxide to guide therapy, as well as treatment with anti-IgE antibody, methotrexate, macrolide antibiotics, antifungal agents and bronchial thermoplasty are provided. Coordinated research efforts for improved phenotyping will provide safe and effective biomarker-driven approaches to severe asthma therapy. ERS/ATS guidelines revise the definition of severe asthma, discuss phenotypes and provide guidance on patient management http://ow.ly/roufI


Journal of Clinical Epidemiology | 2011

GRADE guidelines: 4. Rating the quality of evidence—study limitations (risk of bias)

Gordon H. Guyatt; Andrew D Oxman; Gunn Elisabeth Vist; Regina Kunz; Jan Brozek; Pablo Alonso-Coello; Victor M. Montori; Elie A. Akl; Ben Djulbegovic; Yngve Falck-Ytter; Susan L. Norris; John W Williams; David Atkins; Joerg J. Meerpohl; Holger J. Schünemann

In the GRADE approach, randomized trials start as high-quality evidence and observational studies as low-quality evidence, but both can be rated down if most of the relevant evidence comes from studies that suffer from a high risk of bias. Well-established limitations of randomized trials include failure to conceal allocation, failure to blind, loss to follow-up, and failure to appropriately consider the intention-to-treat principle. More recently recognized limitations include stopping early for apparent benefit and selective reporting of outcomes according to the results. Key limitations of observational studies include use of inappropriate controls and failure to adequately adjust for prognostic imbalance. Risk of bias may vary across outcomes (e.g., loss to follow-up may be far less for all-cause mortality than for quality of life), a consideration that many systematic reviews ignore. In deciding whether to rate down for risk of bias--whether for randomized trials or observational studies--authors should not take an approach that averages across studies. Rather, for any individual outcome, when there are some studies with a high risk, and some with a low risk of bias, they should consider including only the studies with a lower risk of bias.


Journal of Clinical Epidemiology | 2011

GRADE guidelines: 7. Rating the quality of evidence--inconsistency

Gordon H. Guyatt; Andrew D Oxman; Regina Kunz; James Woodcock; Jan Brozek; Mark Helfand; Pablo Alonso-Coello; Paul Glasziou; Roman Jaeschke; Elie A. Akl; Susan L. Norris; Gunn Elisabeth Vist; Philipp Dahm; Vijay K. Shukla; Julian P. T. Higgins; Yngve Falck-Ytter; Holger J. Schünemann

This article deals with inconsistency of relative (rather than absolute) treatment effects in binary/dichotomous outcomes. A body of evidence is not rated up in quality if studies yield consistent results, but may be rated down in quality if inconsistent. Criteria for evaluating consistency include similarity of point estimates, extent of overlap of confidence intervals, and statistical criteria including tests of heterogeneity and I(2). To explore heterogeneity, systematic review authors should generate and test a small number of a priori hypotheses related to patients, interventions, outcomes, and methodology. When inconsistency is large and unexplained, rating down quality for inconsistency is appropriate, particularly if some studies suggest substantial benefit, and others no effect or harm (rather than only large vs. small effects). Apparent subgroup effects may be spurious. Credibility is increased if subgroup effects are based on a small number of a priori hypotheses with a specified direction; subgroup comparisons come from within rather than between studies; tests of interaction generate low P-values; and have a biological rationale.


Journal of Clinical Epidemiology | 2011

GRADE guidelines: 8. Rating the quality of evidence-Indirectness

Gordon H. Guyatt; Andrew D Oxman; Regina Kunz; James Woodcock; Jan Brozek; Mark Helfand; Pablo Alonso-Coello; Yngve Falck-Ytter; Roman Jaeschke; Gunn Elisabeth Vist; Elie A. Akl; Piet N. Post; Susan L. Norris; Joerg J. Meerpohl; Vijay K. Shukla; Mona Nasser; Holger J. Schünemann

Direct evidence comes from research that directly compares the interventions in which we are interested when applied to the populations in which we are interested and measures outcomes important to patients. Evidence can be indirect in one of four ways. First, patients may differ from those of interest (the term applicability is often used for this form of indirectness). Secondly, the intervention tested may differ from the intervention of interest. Decisions regarding indirectness of patients and interventions depend on an understanding of whether biological or social factors are sufficiently different that one might expect substantial differences in the magnitude of effect. Thirdly, outcomes may differ from those of primary interest-for instance, surrogate outcomes that are not themselves important, but measured in the presumption that changes in the surrogate reflect changes in an outcome important to patients. A fourth type of indirectness, conceptually different from the first three, occurs when clinicians must choose between interventions that have not been tested in head-to-head comparisons. Making comparisons between treatments under these circumstances requires specific statistical methods and will be rated down in quality one or two levels depending on the extent of differences between the patient populations, co-interventions, measurements of the outcome, and the methods of the trials of the candidate interventions.


Journal of Clinical Epidemiology | 2011

GRADE guidelines: 2. Framing the question and deciding on important outcomes

Gordon H. Guyatt; Andrew D Oxman; Regina Kunz; David Atkins; Jan Brozek; Gunn E Vist; Philip Alderson; Paul Glasziou; Yngve Falck-Ytter; Holger J. Schünemann

GRADE requires a clear specification of the relevant setting, population, intervention, and comparator. It also requires specification of all important outcomes--whether evidence from research studies is, or is not, available. For a particular management question, the population, intervention, and outcome should be sufficiently similar across studies that a similar magnitude of effect is plausible. Guideline developers should specify the relative importance of the outcomes before gathering the evidence and again when evidence summaries are complete. In considering the importance of a surrogate outcome, authors should rate the importance of the patient-important outcome for which the surrogate is a substitute and subsequently rate down the quality of evidence for indirectness of outcome.


Journal of Clinical Epidemiology | 2011

GRADE guidelines: 5. Rating the quality of evidence—publication bias

Gordon H. Guyatt; Andrew D Oxman; Victor M. Montori; Gunn Elisabeth Vist; Regina Kunz; Jan Brozek; Pablo Alonso-Coello; Ben Djulbegovic; David Atkins; Yngve Falck-Ytter; John W Williams; Joerg J. Meerpohl; Susan L. Norris; Elie A. Akl; Holger J. Schünemann

In the GRADE approach, randomized trials start as high-quality evidence and observational studies as low-quality evidence, but both can be rated down if a body of evidence is associated with a high risk of publication bias. Even when individual studies included in best-evidence summaries have a low risk of bias, publication bias can result in substantial overestimates of effect. Authors should suspect publication bias when available evidence comes from a number of small studies, most of which have been commercially funded. A number of approaches based on examination of the pattern of data are available to help assess publication bias. The most popular of these is the funnel plot; all, however, have substantial limitations. Publication bias is likely frequent, and caution in the face of early results, particularly with small sample size and number of events, is warranted.


Clinical Infectious Diseases | 2016

Management of Adults With Hospital-acquired and Ventilator-associated Pneumonia: 2016 Clinical Practice Guidelines by the Infectious Diseases Society of America and the American Thoracic Society.

Andre C. Kalil; Mark L. Metersky; Michael Klompas; John Muscedere; Daniel A. Sweeney; Lucy B. Palmer; Lena M. Napolitano; Naomi P. O'Grady; John G. Bartlett; Jordi Carratalà; Ali A. El Solh; Santiago Ewig; Paul D. Fey; Thomas M. File; Marcos I. Restrepo; Jason A. Roberts; Grant W. Waterer; Peggy E. Cruse; Shandra L. Knight; Jan Brozek

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patients individual circumstances.These guidelines are intended for use by healthcare professionals who care for patients at risk for hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP), including specialists in infectious diseases, pulmonary diseases, critical care, and surgeons, anesthesiologists, hospitalists, and any clinicians and healthcare providers caring for hospitalized patients with nosocomial pneumonia. The panels recommendations for the diagnosis and treatment of HAP and VAP are based upon evidence derived from topic-specific systematic literature reviews.


World Allergy Organization Journal | 2009

Sub-Lingual Immunotherapy: World Allergy Organization Position Paper 2009

G. Walter Canonica; Jean Bousquet; Thomas Casale; Richard F. Lockey; Carlos E. Baena-Cagnani; Ruby Pawankar; Paul C. Potter; Philippe Jean Bousquet; Linda Cox; Stephen R Durham; Harold S. Nelson; Giovanni Passalacqua; Dermot Ryan; Jan Brozek; Enrico Compalati; Ronald Dahl; Luís Delgado; Roy Gerth van Wijk; Richard G. Gower; Dennis K. Ledford; Nelson Augusto Rosário Filho; E. Valovirta; O. M. Yusuf; Torsten Zuberbier; Wahiduzzaman Akhanda; Raúl Lázaro Castro Almarales; Ignacio J. Ansotegui; Floriano Bonifazi; Jan Ceuppens; Tomás Chivato

Chair: G. Walter Canonica Co-Chairs Jean Bousquet, Thomas Casale, Richard F. Lockey, Carlos E. Baena-Cagnani, Ruby Pawankar, Paul C. Potter Authors Philippe J. Bousquet, Linda S. Cox, Stephen R. Durham, Harold S. Nelson, Giovanni Passalacqua, Dermot P. Ryan, Jan L. Brozek, Enrico Compalati, Ronald Dahl, Luis Delgado, Roy Gerth van Wijk, Richard G. Gower, Dennis K. Ledford, Nelson Rosario Filho, Erkka J. Valovirta, Osman M. Yusuf, Torsten Zuberbier Co-Authors Wahiduzzaman Akhanda, Raul Castro Almarales, Ignacio Ansotegui, Floriano Bonifazi, Jan Ceuppens, Tomás Chivato, Darina Dimova, Diana Dumitrascu, Luigi Fontana, Constance H. Katelaris, Ranbir Kaulsay, Piotr Kuna, Désirée Larenas-Linnemann, Manolis Manoussakis, Kristof Nekam, Carlos Nunes, Robyn O’Hehir, José M. Olaguibel, Nerin Bahceciler Onder, Jung Won Park, Alfred Priftanji, Robert Puy, Luis Sarmiento, Glenis Scadding, Peter Schmid-Grendelmeier, Ester Seberova, Revaz Sepiashvili, Dírceu Solé, Alkis Togias, Carlo Tomino, Elina Toskala, Hugo Van Beever, Stefan Vieths

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Elie A. Akl

American University of Beirut

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Andrew D Oxman

Norwegian Institute of Public Health

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