Adaptive randomization is used to support the statistical methodology of a clinical trial by maintaining balance among treatments for the analysis population and subgroups (or strata). With this technology individual subject response information is maximized, especially important for studies involving rare conditions, terminally ill patients, and for studies terminated early.
In determining the random adaptive algorithm the clinical trial statistician considers the statistical methodology, or model statement, to be used for the primary efficacy variable. Prognostic factors are incorporated into the random adaptive algorithm in a parallel design to best support the planned statistical analyses. Theoretical frameworks are either frequentist or Bayesian.
The process of developing the random adaptive module of the automated randomization system is delineated including re-sequencing, re-randomization and reporting of randomization transactions. Implementation of an adaptive randomization is relatively easy so that efficiencies of design to achieve balances which support the statistical analysis and reporting accountability are well worth the implementation effort.
Interactive Clinical Technologies Incorporated (ICTI) has been implementing adaptive randomization designs in clinical trials since 1999 and has participated in over 75 adaptive randomization studies of varying complexity.