title: [GRADE guidelines: 9. Rating up the quality of evidence].
abstract: 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.
authors.affiliation: Donau-Universität Krems, Department für Evidenzbasierte Medizin und Klinische Epidemiologie, Krems, Austria. christina.kien@donau-uni.ac.at
authors.forename: Christina
authors.initials: C
authors.lastname: Kien
authors.forename: Gerald
authors.initials: G
authors.lastname: Gartlehner
authors.forename: Angela
authors.initials: A
authors.lastname: Kaminski-Hartenthaler
authors.forename: Joerg J
authors.initials: JJ
authors.lastname: Meerpohl
authors.forename: Maria
authors.initials: M
authors.lastname: Flamm
authors.forename: Gero
authors.initials: G
authors.lastname: Langer
authors.forename: Matthias
authors.initials: M
authors.lastname: Perleth
authors.forename: Holger J
authors.initials: HJ
authors.lastname: Schünemann
mesh_terms: D001317:Austria; D015982:Bias; D019317:Evidence-Based Medicine / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D064887:Observational Studies as Topic; D010043:Outcome and Process Assessment, Health Care / Q000592:standards*; D012046:Rehabilitation / Q000592:standards* / Q000706:statistics & numerical data; D012107:Research Design / Q000592:standards* / Q000706:statistics & numerical data