What Is the Question?

  • Lawrence M. Friedman
  • Curt D. Furberg
  • David L. DeMets


The planning of a clinical trial depends on the question that the investigator is addressing. The general objective is usually obvious, but the specific question to be answered by the trial is often not stated well. Stating the question clearly and in advance encourages proper design. It also enhances the credibility of the findings. One would like answers to a number of questions, but the study should be designed with only one major question in mind. This chapter discusses the selection of this primary question and appropriate ways of answering it. In addition, types of secondary and subsidiary questions are reviewed.


Response Variable Total Mortality Nonfatal Myocardial Infarction Primary Question Noninferiority Trial 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer New York 2010

Authors and Affiliations

  • Lawrence M. Friedman
    • 1
  • Curt D. Furberg
    • 2
  • David L. DeMets
    • 3
  1. 1.BethesdaUSA
  2. 2.School of MedicineWake Forest UniversityWinston-SalemUSA
  3. 3.Department of Biostatistics & Medical InformaticsUniversity of WisconsinMadisonUSA

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