1] Centre for Liver Research and National Institute for Health Research Birmingham Liver Biomedical Research Unit, University of Birmingham, Birmingham, UK  Liver and Hepatobiliary Unit, Queen Elizabeth Hospital Birmingham, Birmingham, UK  Hepatitis C Virus Research Group, University of Birmingham, Birmingham, UK.
We aimed to describe the overall quality of evidence supporting international guidelines in liver disease.
The quality of evidence supporting guidelines from three international liver disease associations was graded as high, moderate, or low according to the systems initially used to assess the primary literature.
Twenty-three current guidelines were developed with the use of five evidence-grading systems. Evidence was assessed as low-quality (from consensus opinions) in 43.9% of all recommendations. Recommendations based on high-quality evidence (from consistent data from randomized controlled trials) appeared least frequently. Where guidelines had been updated, there was a 22% increase in the total number of recommendations, due largely to an increase in recommendations based on low-quality evidence. Recommendations revised to include high-quality evidence accounted for only 16.3% of all new or updated recommendations.
Guidelines in liver disease are heterogeneous. Evidence-based recommendations in these guidelines are most frequently based on low-quality evidence.