Early Stopping with East SEQUENTIAL

East SEQUENTIAL provides accurate early stopping tools that are essential for conducting cost-effective clinical studies. Early stopping calculations report the probability that a trial will yield statistically significant results. They can be conducted midway through the trial to determine whether or not it would be productive for the trial to continue.

A cornerstone of the East guide to clinical success is its selection of finely tested, state-of-the-art methods for early stopping. East provides a host of validated stopping rules for efficacy and futility, to determine the benefits of continuing time-consuming, resource-consuming trials.
East SEQUENTIAL enables customers to implement East ADAPT, East SURVIVAL, East SURVADAPT and East PREDICT.


East SEQUENTIAL creates elegant charts that illustrate the value-gained from various early-stopping boundaries, highlighting alternatives that simplify and clarify design options. An extensive selection of stopping-rules and spending functions inform optimal trial design by capturing differences in time, cost-effectiveness and sample size.

The ability to compute and compare conditional and predictive power at the interim stage plays an integral role in enhanced monitoring strategy. East SEQUENTIAL provides opportunities to update efficacy and (or) futility boundaries after each stage of hypothesis testing. A wide assortment of stopping-boundaries and boundary scales provide unparalleled decision-making tools. East SEQUENTIAL can also display boundaries on multiple scales.


Features and Options

Charts and Tables

  • Stopping Boundaries
  • Scales: Z, Score, P-value, Delta, Delta/Sigma
  • Error Spending
  • Average Sample Number


  • Error Spending Functions
  • Lan-Demets [Pocock, O’Brien-Fleming]
  • Gamma, Rho, Interpolated
  • Generalized Haybittle-Peto
  • Wang-Tsiatis
  • Non-Binding Futility
  • Pampallona-Tsiatis, P-value, Conditional Power
  • Delta/Sigma
  • Flexible Boundaries
  • Efficacy and/or Futility at Selected Looks
  • Unequal Spacing of Looks

Interim Monitoring Dashboard

  • Track Error Spent, Update Boundaries
  • Conditional and Predictive Power
  • Bias-corrected Inference
  • Adjusted P-values, Point Estimates
  • Confidence Intervals

Common risk ratio design, simulation and interim monitoring

Trials with super-superiority hypothesis

Trials with equivalence hypothesis