Quality of Clinical Practice Guidelines for Glycemic Control in Type 2 Diabetes Mellitus

Background: Several studies have reported that clinical practice guidelines (CPGs) in a variety of clinical areas are of modest or variable quality. The objective of this study was to evaluate the quality of an international cohort of CPGs that provide recommendations on pharmaceutical management of glycemic control in patients with type 2 diabetes mellitus (DM2). Methods and Findings: We searched the National Guideline Clearinghouse (NGC) on February 15th and June 4th, 2012 for CPGs meeting inclusion criteria. Two independent assessors rated the quality of each CPG using the Appraisal of Guidelines for Research & Evaluation II (AGREE II) instrument. Twenty-four guidelines were evaluated, and most had high scores for clarity and presentation. However, scope and purpose, stakeholder involvement, rigor of development, and applicability domains varied considerably. The majority of guidelines scored low on editorial independence, and only seven CPGs were based on an underlying systematic review of the evidence. Conclusions: The overall quality of CPGs for glycemic control in DM2 is moderate, but there is substantial variability among quality domains within and across guidelines. Guideline users need to be aware of this variability and carefully appraise and select the guidelines that they apply to patient care.