Our low cost simple service is quick and easy to set up yourself online. By upgrading to our Simple + service you get access to additional customisation features (see below). We recommend our comprehensive service for Clinical Trials of Investigational Medicinal Products (CTIMPs) because it provides a full audit log and role based user accounts.

Why not try the service out by creating a test trial first? This will allow you to become familiar with the way the system works before setting it up for use in your real trial.

How it works

Patients are randomised to one of two treatment groups ('A' or 'B') and the result recorded. Randomisation is blocked (using random permuted blocks) to ensure that the groups are balanced periodically.

There is a single password for a trial and anyone with the password may carry out new randomisations for that trial. The randomisation results are shown on-screen and emailed to both the administrator of the trial and to the randomiser. Read the full specification.

You can increase the randomisation limit to suit your sample size by buying more randomisations at any time. See pricing.

Simple +

Upgrade to our Simple + service and get access to these additional features:

  • Stratify, e.g. by age group or centre
  • Name your treatment groups, e.g. Placebo and Aspirin rather than A and B
  • Alter the allocation ratio from 1:1, for example to 2:1
  • Have more than two treatment groups
  • Choose your own block sizes
  • Add eligibility criteria that must be met to allow randomisation
  • Randomise by text message - try the demo now!

To get your free 50 randomisations make sure you don't choose any of these paid options when creating your trial.

Walkthrough Follow a worked example to create a trial using a randomisation list.

How to cite this service

Sealed Envelope Ltd. 2022. Simple randomisation service. [Online] Available from: https://www.sealedenvelope.com/simple-randomiser/v1/ [Accessed 12 Jul 2024].

Find an existing trial

Get started!

Create a new trial

Free for 50 randomisations

excluding Simple + service