Clarification of the Nature and Use of the ACR Appropriateness Criteria in Decision-Support Trials

We are writing in response to the recently published article by Rosenkrantz et al. ( ). In the article, the authors point out that the Appropriateness Criteria (AC) of the American College of Radiology (ACR) provide guidance for many clinical concerns in the abdomen, but not for a majority of them, in the practice of a large urban academic medical center. We have been associated with the AC for a long time and wish to thank the authors of this article for their thoughtful and useful study and to provide some perspective. Although clearly not perfect, the AC, as the authors note, are the most complete and methodologically sound clinical imaging guidelines available. The process for creating, revising, and maintaining the AC is rigorous and time consuming and depends on the dedicated volunteer work of more than 1500 current and former panel members. Currently, there are more than 450 radiologists, radiation oncologists, and consultants from more than 20 other medical specialties, all volunteers, at work on the panels with important administrative support from the ACR. The AC were begun in 1993, to provide guidance as to which imaging test or tests, if any, would be most likely to be helpful in a specific clinical scenario. They were intended to provide both education and clinical guidance. Since 1996, the number of AC topics has nearly doubled (from 116 to over 200) and the number of variants has increased from 600 to over 980. New AC have been created to address scenarios that are important in terms of clinical impact, use of imaging, cost, and prevalence. The process of developing and revising each AC is well defined, comprehensive, and expensive. It is based on the RAND Corporation/University of California, Los Angeles Appropriateness Method User's Manual ( ). It begins with a systematic review of the published literature, including synthesis of the evidence and rating of the quality of the relevant peer-reviewed articles, followed by creation of a narrative addressing the topic, and then, with the use of the modified Delphi method, creation of a table of recommendations on the basis of benefits and harms. Topics are regularly updated, to ensure that they are based, to as great an extent as possible, on the most current, relevant literature. This rigorous methodology and the substantial time demands imposed by it of necessity limit the number of clinical problems that can be addressed.