The Agency for Healthcare Research and Quality (AHRQ), through its Evidence-based Practice Centers (EPCs), sponsors the development of evidence reports and technology assessments to assist public- and private-sector organizations in their efforts to improve the quality of healthcare in the United States. The reports and assessments provide organizations with comprehensive, science-based information on common, costly medical conditions and new healthcare technologies and strategies. The EPCs systematically review the relevant scientific literature on topics assigned to them by AHRQ and conduct additional analyses when appropriate prior to developing their reports and assessments.

Strong methodological approaches to systematic review improve the transparency, consistency, and scientific rigor of these reports. Through a collaborative effort of the Effective Health Care (EHC) Program, the Agency for Healthcare Research and Quality (AHRQ), the EHC Program Scientific Resource Center, and the AHRQ Evidence-based Practice Centers have developed a Methods Guide for Comparative Effectiveness Reviews. This Guide presents issues key to the development of systematic reviews and describes recommended approaches for addressing difficult, frequently encountered methodological issues.

The Methods Guide for Comparative Effectiveness Reviews is a living document and will be updated as further empiric evidence develops and our understanding of better methods improves.

If you have comments on this Methods Guide paper, they may be sent by mail to the Task Order Officer named below at: Agency for Healthcare Research and Quality, 5600 Fishers Lane, Rockville, MD 20857, or by email to vog.shh.qrha@cpe.

• Robert Otto Valdez, Ph.D., M.H.S.A.
  Director
  Agency for Healthcare Research and Quality
• Craig A. Umscheid, M.D., M.S.
  Director
  Evidence-based Practice Center Program
  Center for Evidence and Practice Improvement
  Agency for Healthcare Research and Quality
• Arlene S. Bierman, M.D., M.S.
  Director
  Center for Evidence and Practice Improvement
  Agency for Healthcare Research and Quality
• Lionel L. Bañez, M.D.
  Task Order Officer
  Center for Evidence and Practice Improvement
  Agency for Healthcare Research and Quality