Definitions

Understanding Guideline Language

Best Evidence Synthesis 
We include only the best available evidence for any given outcome addressing a recommendation. Accordingly, we first included the highest quality evidence for any given outcome if it was available. In the absence of two or more occurrences of an outcome at this quality, we considered outcomes of the next lowest quality until at least two or more occurrences of an outcome had been acquired. For example, if there were two ‘moderate’ quality occurrences of an outcome that addressed a recommendation, we did not include ‘low’ quality occurrences of this outcome. 

Current Quality Requirements (6/2013 - Present)
Strong - Two or more HIGH quality studies
Moderate - One HIGH or 2 MODERATE quality studies
Limited - One MODERATE or 1 or more LOW quality studies
Consensus – Expert opinion (no studies)*
*Only used in one circumstance: It pertains to medical interventions that potentially prevent loss of life or limb (catastrophic consequences).
 
Previous Quality Requirements (7/2009 – 5/2013)
Strong - Two or more HIGH quality studies
Moderate - One HIGH or 2 MODERATE quality studies
Limited - One MODERATE or 2 LOW quality studies
Consensus – Expert opinion (no studies)**
Inconclusive – One LOW quality study, Contradictory studies, Lack of evidence (no studies)
 ** For the work group to make a consensus-based recommendation, the recommendation must be supported by a rationale that follows specific rules.

Language Stems
To prevent bias in the way recommendations are worded, the AAOS uses specific predetermined language stems that are governed by the evidence strengths. Each recommendation was written using language that accounts for the final strength of the recommendation. 

Current Language Stems (6/2013 - Present)
Strong - Strong evidence supports that the practitioner should/should not do X, because…
Moderate - Moderate evidence supports that the practitioner could/could not do X, because…
Limited - Limited evidence supports that the practitioner might/might not do X, because…
Consensus - In the absence of reliable evidence, it is the opinion of the work group that…
 
 Previous Language Stems (7/2009 - 5/2013)
Strong - We recommend… or We cannot recommend
Moderate - We suggest…
Limited - It is an option…
Consensus - In the absence of reliable evidence, it is the opinion of the work group…
Inconclusive - We are unable to recommend for or against…