clinIT offers interactive voice response (IVR) and interactive web response (IWR) systems as tools to support central randomization.

In addition, our IVR and IWR can be used to support or control-check other parts of a clinical trial, including recruitment rates, 24-hour emergency codebreak services, management and re-supply of study treatment at the site. The main method of randomization is treatment allocation using a list of permuted blocks.

For stratifying confounders, the list is divided into sections - one for each stratum defined by the cross-classification of factor levels. If there are many stratifying factors, then the balancing of stratified randomization becomes more and more difficult when using randomization lists. An alternative is dynamic allocation via central randomization by an IVRS. A commonly used dynamic allocation technique is minimization with biased coin assignment or Zelen’s method.

clinIT’s IVR/IWR system facilitates the execution of trials with an adaptive design. With our IVRS, adaptations, such as change of allocation ratio or drop of treatment arms, can be easily implemented in an ongoing study.