Impact of Drug Adherence in Clinical Trials

  • Michel BurnierEmail author
Part of the Updates in Hypertension and Cardiovascular Protection book series (UHCP)


In randomized clinical trials assessing the efficacy or benefits of a new drug treatment or a new treatment strategy, it is generally assumed that patients follow strictly the recommendations on how and when to take their medications. Therefore, little attention is given to adherence and this latter is rarely measured adequately. When it is, data are often handled inappropriately. The purpose of this chapter is to discuss the problems of drug adherence in clinical trials and to review the multiple consequences that a low adherence might have such as failure to demonstrate efficacy, underestimation of the drug efficacy, underestimation of safety concerns, and increased study costs.


Evidence based medicine Clinical trials Randomization Meta-analysis 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Service of Nephrology and Hypertension, Department of MedicineCentre Hospitalier Universitaire Vaudois (CHUV), University HospitalLausanneSwitzerland

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