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A Note on Correction of Information Time in a Survival Trial Using an Alpha Spending Function

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Abstract

Spending functions allow flexible monitoring of a clinical trial in that neither the number nor timing of the interim analyses need be pre-specified. Instead, we specify a function dictating the amount of alpha to be spent by different fractions of information. With a survival outcome, information is proportional to the number of patients who will have an event by the end of the trial. If the initial estimate of the number of events is incorrect, then we will spend an undesirable amount of alpha at interim looks. This note shows that for the most popular spending functions, which spend very little alpha early, we can fix an underestimate of the final information with very little effect on the boundaries.

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References

  1. Pocock SJ (1977) Group sequential methods in the design and analysis of clinical trials. Biometrika 64:191–199

    Article  Google Scholar 

  2. O’Brien PC, Fleming TR (1979) A multiple testing procedure for clinical trials. Biometrics 35:549–556

    Article  Google Scholar 

  3. Lan KK, DeMets D (1983) Discrete sequential boundaries for clinical trials. Biometrika 70:659–663

    Article  MathSciNet  MATH  Google Scholar 

  4. Lan KK, Zucker DM (1993) Sequential monitoring of clinical trials: The role of information and Brownian motion. Stat. Med. 12:753–765

    Article  Google Scholar 

  5. Proschan MA, Lan KKG, Wittes JT (2006) Statistical monitoring of clinical trials: a unified approach. Springer, New York

    MATH  Google Scholar 

  6. Armitage P, McPherson CK, Rowe BC (1969) Repeated significance tests on accumulating data. J. R. Stat. Soc. A 132:235–244

    Article  MathSciNet  Google Scholar 

  7. Lan KK, DeMets DL (1989) Group sequential procedures: calendar versus information time. Stat. Med. 8:1191–1198

    Article  Google Scholar 

  8. Lan KK, Lachin JM (1990) Implementation of group sequential logrank tests in a maximum duration trial. Biometrics 46:759–770

    Article  Google Scholar 

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Authors and Affiliations

  1. National Institute of Allergy and Infectious Diseases, 6700A Rockledge Drive, Room 5140, MSC 7609, Bethesda, MD, 20892-7609, USA

    Michael A. Proschan & Martha Nason

Authors
  1. Michael A. Proschan
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  2. Martha Nason
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Correspondence to Michael A. Proschan.

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Proschan, M.A., Nason, M. A Note on Correction of Information Time in a Survival Trial Using an Alpha Spending Function. Stat Biosci 3, 250–259 (2011). https://doi.org/10.1007/s12561-010-9027-9

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  • DOI: https://doi.org/10.1007/s12561-010-9027-9

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