Doenças Vasculares 2009
Preamble
These recommendations provide a data-supported ap- proach. They are based on the following: (1) formal re- view and analysis of the recently published world literature on the topic (Medline search); (2) American College of Physicians Manual for Assessing Health Prac- tices and Designing Practice Guidelines1; (3) guideline policies, including the AASLD Policy on the Develop- ment 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 preventive 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 quality of evidence supporting recommendations, the Practice Guidelines Committee of the AASLD requires a Class (reflecting benefit versus risk) and Level (assessing strength or certainty) of Evidence to be assigned and reported with each recommendation (Table 1, adapted from the American
