AASLD guidelines classification scheme
Editor-In-Chief: C. Michael Gibson, M.S., M.D. 
AASLD (American Association of Study of Liver Disease) provides recommendations for various liver diseases. It develops clinical practice guidelines which are supported by a high level of scientific evidence. They assist in appropriate health care to patients. The clinical practice guidelines should not be looked at as "standards of care". They are provided to aid in the diagnosis and management of liver diseases.
Classification of Recommendations
AASLD recommendations are classified into five grades based on quality of evidence.
|Grade I||Randomized controlled trials|
|Grade II - 1||Controlled trials without randomization|
|Grade II - 2||Cohort or case-control analytic studies|
|Grade II - 3||Multiple time series, dramatic uncontrolled experiments|
|Grade III||Opinions of respected authorities, descriptive epidemiology|
AASLD has adapted the recommendations classification from American Heart Association recommendations classification. The adapated classification is as follows:
Class of recommendation
|Class I||Conditions for which there is evidence and/or general agreement that a given diagnostic evaluation, procedure or treatment is beneficial, useful, and effective.|
|CLass II||Conditions for which there is conflicting evidence and/or a divergence of opinion about the usefulness/efficacy of a diagnostic evaluation, procedure or treatment.|
|Class IIa||Weight of evidence/opinion is in favor of usefulness/ efficacy.|
|Class IIb||Usefulness/efficacy is less well established by evidence/opinion.|
|Class III||Conditions for which there is evidence and/or general agreement that a diagnostic evaluation/procedure/ treatment is not useful/effective and in some cases may be harmful.|
Level of evidence
|Level of Evidence||Description|
|Level A||Data derived from multiple randomized clinical trials or meta-analyses.|
|Level B||Data derived from a single randomized trial, or nonrandomized studies.|
|Level C||Only consensus opinion of experts, case studies, or standard-of-care.|
The AASLD Practice Guidelines Committee has adopted the classification used by the Grading of Recommendation Assessment,Development, and Evaluation (GRADE) workgroup with minor modifications. The classification is as follows
Class of Recommendation
|Strength of Recommendation||Criteria|
|1 (Strong)||Factors influencing the strength of the recommendation included the quality of the evidence, presumed patient-important outcomes, and cost.|
|2 (Weak)||Variability in preferences and values, or more uncertainty. Recommendation is made with less certainty, or higher cost or resource consumption.|
Level of Evidence
|Quality of Evidence||Criteria|
|A (High)||Further research is unlikely to change confidence in the estimate of the clinical effect.|
|B (Moderate)||Further research may change confidence in the estimate of the clinical effect.|
|C (Low)||Further research is very likely to impact confidence on the estimate of clinical effect.|
- ↑ "American Association for the Study of Liver Diseases: Welcome to AASLD". Retrieved 2012-10-25.
- ↑ Woolf SH, Sox HC (1991). "The Expert Panel on Preventive Services: continuing the work of the U.S. Preventive Services Task Force". American Journal of Preventive Medicine. 7 (5): 326–30. PMID 1790039.
- ↑ "GRADE working group". Retrieved 2012-10-28.