RESUMO
Clinical guidelines have become an integral part of clinical care. We assessed professional society-based clinical guidelines from 2012 to 2022 to elucidate the trends in numbers of documents, recommendations, and classes of recommendations. Our results found that 40% of the guidelines do not follow all recommendations made by the Institute of Medicine for trustworthy documents. There has been a significant increase in documents in cardiology, gastroenterology, and hematology/oncology. In addition, of more than 20,000 recommendations, there was significant variability in recommendations made by different professional societies within a specialty. In documents from 11 of the 14 professional societies, more than 50% of the recommendations are supported with the lowest levels of evidence. In cardiology, in addition to the guideline documents, 140 nonguideline documents provide 1812 recommendations using the guideline verbiage, and 74% of the recommendations are supported by the lowest level of evidence. These data have important implications for health care because guidelines and guideline-like documents can be used for health policy issues such as assessment of quality of care, medical liability, education, and payment.