THE RED SECTION The American Journal of GASTROENTEROLOGY VOLUME 108 | NOVEMBER 2013 www.amjgastro.com nature publishing group 1686 In 1990, the Institute of Medicine (IOM) deined practice guide- lines as, “systematically developed statements to assist prac- titioner and patient decisions about appropriate health care for speciic clinical circumstances”(1). he IOM describes ive major ways that guidelines are employed: assisting clinician decision making, educating individuals or groups, assessing and assuring quality of care, guiding allocation of resources, and reducing the risk of legal liability for negligent care (1). However, guidelines are used by groups other than physicians to deine acceptable standards of care. Guidelines are utilized by insurance companies and managed care organizations to determine appropriateness of care, level of coverage, and reimbursements. Similarly, lawyers employ guidelines in mal- practice litigation with the presumption that failure to follow the clinical guidelines constitutes negligence. More recently, medical organizations are using guidelines to publish quality metrics as benchmarks for cost-efective quality care that may then be used to determine physician reimbursement (1–5). It is therefore imperative that guidelines provide up-to-date and accurate information based on the highest level of evidence. Systematic Analysis Underlying the Quality of the Scientific Evidence and Conflicts of Interest in Gastroenterology Practice Guidelines Joseph D. Feuerstein, MD 1 , Anne E. Giford, MPH 1 , Mona Akbari, MD 1 , Jonathan Goldman, MD 1 , Daniel A. Leler , MD, MS 1 , Sunil G. Sheth, MD 1 and Adam S. Cheifetz, MD 1 OBJECTIVES: The practice guidelines published by the American Gastroenterological Association (AGA) and the American College of Gastroenterology (ACG) are used to establish standards of care and improve patient outcomes. We examined the guidelines for quality of evidence, methods of grading evidence, and conflicts of interest (COIs). METHODS: All 81 (AGA and ACG) guidelines available online on 26 July 2012 were reviewed for the presence of grading of evidence and COIs. In total, 570 recommendations were evaluated for level of evidence and methods used to grade the evidence. The data were evaluated in aggregate and by society. RESULTS: Only 31% ( n = 25) of the guidelines graded the levels of evidence. A total of 12 systems were used to grade the quality of evidence in these 25 guidelines. Of the 570 recommendations reviewed, only 29% ( n = 165) were supported by the highest quality of evidence, level A; 37% ( n = 210) level B, 29% ( n = 165) level C, and 5% ( n = 30) level D. Since 2007, 87% ( n = 13/15) of the ACG guidelines graded the evidence compared with only 33% of the AGA guidelines ( n = 4/12). Furthermore, 70% ( n = 57/81) of the guidelines failed to disclose any information regarding COIs. Of the 24 articles commenting on COIs, 67% reported COIs. CONCLUSIONS: Although the majority of the gastroenterology guidelines fail to grade the quality of evidence, more recent ACG guidelines grade majority of their recommendations. When the evidence is graded, most of the supporting evidence is based on lower-quality evidence. In addition, most of the guidelines fail to comment on COIs, and when disclosed, numerous COIs were present. This study highlights the critical need to revise the guideline development process. Future guidelines should clearly state the quality of evidence for their recommendations, utilize a standard grading system, and be transparent regarding all COIs. SUPPLEMENTARY MATERIAL is linked to the online version of the paper at http://www.nature.com/ajg Am J Gastroenterol 2013; 108:1686–1693; doi:10.1038/ajg.2013.150 1 Department of Medicine and Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA. Correspondence: Joseph D. Feuerstein, MD, Department of Medicine and Division of Gastroenterology, Beth Israel Deaconess Medical Center , 330 Brookline Avenue, E/DANA 501, Harvard Medical School, Boston, Massachusetts, USA. E-mail: jfeuerst@bidmc.harvard.edu