Journal of General Internal Medicine

, Volume 25, Issue 9, pp 891–892 | Cite as

N-of-1 Trials: A New Future?

  • Eric B. Larson

The idea of N-of-1 randomized trials first came to my attention at a clinical epidemiology meeting during a presentation by Gordon Guyatt in which he described a dramatic case report of a 65-year-old patient with steroid dependent asthma.1 This case, subsequently published in the New England Journal of Medicine, demonstrated that aminophyllinee, then commonly prescribed for asthma and chronic lung disease was causing great harm to the patient as a result of exacerbation of gastroesophageal reflux. The prospect of improving therapeutic precision and avoiding harm inspired me to form an N-of-1 trial service at University of Washington Medical Center. Although this service was generally successful in achieving its goal of improving therapeutic precision it did not endure much beyond its two year pilot project phase.2 I have since wondered at the contrast between how much effort and expense we devote to diagnostic precision compared with the degree to which medicine accepts imprecision in...


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Copyright information

© Society of General Internal Medicine 2010

Authors and Affiliations

  1. 1.Group Health Research InstituteSeattleUSA

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