What Is the Question?

  • Lawrence M. Friedman
  • Curt D. Furberg
  • David L. DeMets
  • David M. Reboussin
  • Christopher B. Granger


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. The reliability of clinical trial results derives in part from rigorous prospective definition of the hypothesis. This contrasts with observational studies where the analyses are often exploratory, may be part of an iterative process, and therefore more subject to chance [1]. 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 Comparative Effectiveness Research Primary Question 
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 International Publishing Switzerland 2015

Authors and Affiliations

  • Lawrence M. Friedman
    • 1
  • Curt D. Furberg
    • 2
  • David L. DeMets
    • 3
  • David M. Reboussin
    • 4
  • Christopher B. Granger
    • 5
  1. 1.North BethesdaUSA
  2. 2.Division of Public Health SciencesWake Forest School of MedicineWinston-SalemUSA
  3. 3.Department Biostatistics and Medical InformaticsUniversity of WisconsinMadisonUSA
  4. 4.Department of BiostatisticsWake Forest School of MedicineWinston-SalemUSA
  5. 5.Department of MedicineDuke UniversityDurhamUSA

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