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Unplanned adaptations before breaking the blind

Martin Posch1, Michael A Proschan

  • 1European Medicines Agency, 7 Westferry Circus, E14 4HB London, UK. Martin.Posch@ema.europa.eu

Statistics in Medicine
|June 28, 2012
PubMed

Insights

When clinical trial primary outcomes are unreliable, a permutation test can salvage the study if applied before treatment unblinding. This method offers a pragmatic solution, despite potential criticisms.

Area of Science:

  • Clinical Trials
  • Biostatistics
  • Statistical Methods

Background:

  • Clinical trials may encounter unforeseen issues with primary outcome measurement reliability.
  • Rigid adherence to flawed trial designs can compromise study integrity and results.

Purpose of the Study:

  • To explore the utility of permutation tests for salvaging clinical trials with unreliable primary outcomes.
  • To evaluate the feasibility and limitations of modifying trial procedures mid-study.

Main Methods:

  • The study proposes using a permutation test.
  • This statistical method is suggested as a recourse when primary outcome measures are unreliable.
  • The critical timing for implementation is before breaking the treatment blind.

Main Results:

  • Permutation tests can provide a viable alternative to abandoning a flawed clinical trial.
  • This approach allows for study salvage under specific, pre-defined conditions.

Conclusions:

  • Modifying trial procedures, such as employing permutation tests, can be preferable to maintaining a nonsensical design.
  • While not a perfect solution, this method offers a pragmatic approach to address critical issues in clinical trial execution.

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