Introduction to Evidence-Based Medicine, Levels of Evidence, and Systematic Reviews

  • Jennifer J. Shin
  • Christopher J. Hartnick


Diseases of the ears, nose, and throat affect the vast majority of the world’s population. In fact, otolaryngologic complaints are the most common reasons for adult and pediatric outpatient medical visits, and more than three million related surgical procedures are performed annually in the United States alone. Although medical and surgical developments have relentlessly advanced this field, the educational and explanatory literature regarding the evidence supporting those advancements has lagged behind. This deficiency is made more pronounced by burgeoning pressure from the academic medical community, third-party financiers, and members of the legal arena. Such growing responsibility to practice evidence-based medicine requires physicians to understand and critique the millions of articles that have been and continue to be published regarding the treatment of head and neck diseases. Time constraints and the overwhelming number of trials, however, serve as dauinting obstacles for physicians who are now under such pressure to adopt an evidence-based approach.


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Jennifer J. Shin
    • 1
  • Christopher J. Hartnick
    • 2
  1. 1.Harvard Program in Otolaryngology-Head and Neck SurgeryMassachusetts Eye and Ear InfirmaryBostonUSA
  2. 2.Department of OtolaryngologyMassachusetts Eye and Ear InfirmaryBostonUSA

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