This guideline has been approved by the American Association for the Study of Liver Diseases and represents the position of the Association. These recommendations provide a data-supported approach. They are based on the following:(1) formal review and analysis of the recentlypublished world literature on the topic (Medline search);(2) American College of Physicians Manual for Assessing Health Practices and Designing Practice Guidelines1;(3) guideline policies, including the AASLD Policy on the Development and Use of Practice Guidelines and the American Gastroenterological Association Policy Statement on Guidelines2; and (4) the experience of the authors in the specified topic.

Intended for use by physicians, these recommendations suggest preferred approaches to the diagnostic, therapeutic and preventative aspects of care. They are intended to be flexible, in contrast to standards of care, which are inflexible policies to be followed in every case. Specific recommendations are based on relevant published information. To more fully characterize the available evidence supporting the recommendations, the AASLD Practice Guidelines Committee has adopted the