Consumers, patients, health care professionals, and payers need information to make informed medical decisions. CER is the use of evidence to directly compare two or more interventions and strategies to prevent, diagnose, treat, and monitor health conditions. This presentation reviews the types of data used in CER and explores the strengths and weaknesses of different types of studies. Each decision maker must consider the relevance and credibility of the available evidence. The presenter will review the questions that should be considered when evaluating relevance and credibility. CER will continue to play an important role in determining what works best for patients in the future.