An recent update on the 2012 ACP diabetes mellitus guidelines relies on a formal review, which excluded studies in which standard of care was the comparator, and thus excludes most of the key randomized controlled trials in the diabetes arena. An over-reliance on confounded observational studies is a consequence, limiting the usefulness of this update.
Refers to Qaseem, A., Barry, M. J., Humphrey, L. L. & Forciea, M. A. Oral pharmacologic treatment of type 2 diabetes mellitus: a clinical practice guideline update from the American College of Physicians. Ann. Intern. Med.http://dx.doi.org/10.7326/M16-1860 (2017)