In One Sentence ...

The Randomizer provides a self-serve, easy to use, secure and 24 hour-a-day Randomization Service for Multi-Center Clinical Trials that runs exclusively on the Internet.

Easy to Use

Investigators randomize patients with only a few clicks by simply completing an on-screen form with patient details and are immediately notified of the treatment allocation.

Using a flexible role-based access control, trial coordinators can nominate investigators, biometricians, monitors and pharmacists. For multi-center trials, user management can be delegated to participating centers. Trial coordinators can open or stop patient recruitment at any time. They can also choose to be notified via email on events such as randomization, emergency unblinding and others.


Many randomization methods, such as permuted blocks, biased coin, urn randomization, minimization and others, are available. As an additional service for biometricians, the Randomizer provides a powerful simulation tool, which can be used to generate static randomization lists or to test a trial design. The software's GCP-compliance has been confirmed by the Austrian Agency for Health and Food Safety (AGES).


All transactions are logged. The trial's audit trail and the list of randomizations can be downloaded and analyzed at any time by the trial monitor. Network traffic between the web-browser and the Randomizer is encrypted using TLS (Transport Layer Security) with strong encryption. TLS is the industry standard security technology for creating an encrypted link between a web server and a browser and is widely used for Internet banking and e-commerce.

See for Yourself

A fully functional demo is available so you can see how the service works.

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