Monitoring Response Variables

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


The investigator’s ethical responsibility to the study participants demands that results in terms of safety and clinical benefit be monitored during trials. If data partway through the trial indicate that the intervention is harmful to the participants, early termination of the trial should be considered. If these data demonstrate a clear benefit from the intervention, the trial may also be stopped early because to continue would be unethical to the participants in the control group. In addition, if differences in primary and possibly secondary response variables are so unimpressive that the prospect of a clear result is extremely unlikely, it may not be justifiable in terms of time, money, and effort to continue the trial. Also, monitoring of response variables can identify the need to collect additional data to clarify questions of benefit or toxicity that may arise during the trial. Finally, monitoring may reveal logistical problems or issues involving data quality that need to be promptly addressed.


Interim Analysis Adaptive Design Monitoring Committee Conditional Power Cardiac Arrhythmia Suppression 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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