There seemed to be many systems for rating literature but few that met the needs of the busy practitioner trying to make sense of individual clinical trials and the hundreds of both evidence-based and consensus-based guidelines that seemed to spring up overnight. In 2004, the editors of the U.S. family medicine and primary care journals and the Family Practice Inquiries Network published a paper on a unified taxonomy called Strength of Recommendation (SOR) Taxonomy that seemed to fit the bill (Figure A-1).3 This taxonomy made use of existing systems for judging study quality while incorporating the concept of patient-oriented (e.g., mortality, morbidity, symptom improvement) rather than disease-oriented (e.g., change in blood pressure, blood chemistry) outcomes as most relevant. A SOR A recommendation is one based on consistent, good-quality patient-oriented evidence; SOR B is a recommendation based on inconsistent or limited-quality patient-oriented evidence; and SOR C is a recommendation based on consensus, usual practice, opinion, disease- oriented evidence, or case series (Figure A-1 and A-2).