From its inception in 1971, the AMA Guides quickly became the acknowledged authority in its field. The new edition of Guides carries on this legacy, giving practitioners and non-medical professionals an updated standard in quality evaluations. It is the approved uniform way to evaluate, measure and report impairment. This edition incorporates the latest diagnostic criteria, using the most current scientific evidence from each specialty and a clinical consensus. It was developed by experts representing the major medical specialties. It covers all body systems and contains significant improvements in major chapters including cardiology, respiratory, musculoskeletal and skin. New conditions covered include HIV and latex allergy. In addition, this edition offers user-friendly formatting with consistency among chapters, and improved references and bibliography. Guides is legally mandated or recommended for use in 40 states, and is also used in Australia and Canada.