In an era of evidence-based medicine, the world is awash in guidelines for appropriate care. How confident can patients and providers be that once a guideline is promulgated, someone is ensuring that it stays consistent with current scientific findings. Not very, according to a study published in the Journal of the American Medical Association. (JAMA Article) For a guideline to be up-to-date, someone needs to be tracking the relevant research and other factors affecting it, such as changes in outcomes being looked at; then their needs to be a process to actually revise the guideline, which can be quite time-consuming; and finally, the new guideline needs to be communicated to practitioners. The authors studied the class one recommendations from the American College of Cardiology/American Heart Association published between 1998 and 2007 and revised between 2006 and 2013. Class one recommendations are the most definitive statement in regard to care, basically saying that this should be done. From the initial recommendation, they considered one of four outcomes–the guideline was fully retained, the guideline was downgraded from class one to a less mandatory status, the guideline was reversed or the recommendation was omitted in subsequent versions of the guideline. The researchers identified 619 class one recommendations in 11 guidelines. Of these 495 were retained in subsequent versions of the guideline, 57 were downgraded or reversed and 67 were omitted. About 20% of recommendations had some change. As might be expected, those guidelines with the greatest level of strength of evidence initially, were least likely to see a change in status in revisions. An accompanying editorial notes that the process for reviewing and revising guidelines can take years. Given that 20% of recommendations, at least in cardiology, were subject to a change, that seems to be too long. As the editorial suggests, some method is needed for more quickly identifying potential changes and getting agreement to make the revision. Otherwise providers may be unaware of potential issues in how they are treating patients. At a minimum a widespread method of alerting doctors that there may be reason to reconsider a particular recommendation would be advisable.