Interested in live on-site STOPP® Seminar? Learn more...

Join ED in Washington, DC... The innovative adaptive design was made possible by the methods developed by Ed Lakatos, which are currently available only in the software STOPP®

4th Annual Trial Design Innovation - Accelerating Safer Drug, Device and Biologic Development with Adaptive Trials:
July 14- 15, 2009 at Washington DC

Cardiovascular Trial: Designing for a Range of Alternatives in the Presence of Non-Proportional Hazards
Edward Lakatos, PhD, President, BIOSTATHAVEN, INC.

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The Clinical Trial Results website provides an excellent database of PowerPoint slides which can be used in conjunction with STOPP® to design new trials. Search the left navigation bar for specific therapeutic area of interest. See tutorial example below:

Flash video player View Tutorial: Use Adobe Acrobat to prepare a PowerPoint survival curve for analysis with STOPP®


Key Publications

  • Armitage P, McPherson CK, Rowe BC. Repeated significance tests on accumulating data. Journal of the Royal Statistical Society, Series A 1969; 132:235-244.

  • Huang IK, Shih WJ, DeCani JS. Group sequential designs using a family of Type I error probability spending functions. Statistics in Medicine 1990; 9: 1439-1445.

  • Pocock SJ. Group sequential methods in the design of clinical trials. Biometrika 1977; 64:191-199

  • O’Brien PC, Fleming TR. A multiple testing procedure for clinical trials. Biometrics 1979; 35:549-556.

  • Lan KKG, DeMets DL. Discrete sequential boundaries for clinical trials. Biometrika 1983; 70:659-663.

  • Lan KKG, DeMets DL. Group sequential procedures: Calendar versus information time. Statistics in Medicine 1989; 8:1191-1198.

  • Lan KKG, DeMets DL. Changing frequency of interim analysis in sequential monitoring. Biometrics 1989; 45:1017-1020.

  • Lakatos, E. Sample sizes for clinical trials with time dependent rates of losses and non-compliance. Controlled Clinical Trials 1986; 7:189-199.

  • Lakatos E. Sample size based on the logrank statistic in complex clinical trials. Biometrics 1988; 44:229-241.

  • Lakatos E, Lan KKG. A comparison of sample size methods for the logrank statistic. Statistics in Medicine 1992; 11:179-191.

  • Lakatos E. Designing complex group-sequential survival trials. Statistics in Medicine 2002; 21:1969-1989.

  • Lan KKG, Zucker DM. Sequential monitoring of clinical trials: the role of information and Brownian motion. Statistics in Medicine 1993; 12:753-765.

  • Procshan MA, Lan KKG, Wittes JT. Statistical Monitoring of Clinical Trials – A Unified Approach. 2006 Springer, NY.

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STOPPĀ® software was made possible by SBIR Grant Number R44CA101617 from the National Cancer Institute of the National Institutes of Health.