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Randomisation and online databases for clinical trials

Sealed Envelope provide high quality and easy to use online software applications for randomising patients into clinical trials and recording their case report form data (EDC and ePRO).

Randomisation & Code break

Proven, reliable, centralised randomisation services to suit every type of randomised clinical trial (RCT). Tell us about your clinical trial and we can set up a randomisation or code break system to meet your requirements. With over 15 years of experience, and a range of automated systems for randomisation by internet or text message, you can trust Sealed Envelope with your trial.

We have two options for randomisation comprehensive and simple.

Comprehensive randomisation service

Use our comprehensive randomisation service to randomise patients online. Code breaking can also be performed by authorised users. Learn more

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Expert set-up

A qualified statistician will oversee the creation of your system. We can give you advice if required on the options available to suit your trial.

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Customised to your trial

Each system is tailored to fit your trial so you only get the features you need. This makes the system easier to use by hiding unnecessary complexity.

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Control panel for trial managers

Users with administrator accounts can view all randomisations as well as reports showing randomisations by site, investigator and over time.

Simple randomisation service

We also offer a simple randomisation service intended for non-commercial clinical trials that do not require minimisation. Get started!


Online set up

You set-up the system yourself online. It only takes a few minutes and you can be randomising immediately!

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Free for up to 50 randomisations

The first 50 randomisations for simple systems are free. Optional features such as stratification, named treatment groups and unequal allocation can be activated for a low fee.


Randomisation by text message

An option to allow randomisation by sending a text message can be added to your simple system. This is useful for users in the field who may not have good internet access.

Red Pill

Red Pill is Sealed Envelope's online database application for electronic data capture (EDC) and ePRO - recording case report form data for patients participating in clinical trials. Investigators and subjects enter forms directly online, and trial managers can manage the data in real time. Learn more

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Contact us if you would like a demonstration of our comprehensive randomisation service or Red Pill, have any specific queries about our services or would like a quote for your clinical trial.

Client testimonials

Our systems have randomised thousands of patients in hundreds of trials.

Published studies that used Sealed Envelope

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Sealed Envelope is certified as meeting the standards ISO/IEC 27001 information security management, Cyber Essentials, and NHS England Data Security and Protection Toolkit. We are registered with the UK Information Commissioner's Office and comply with UK/EU GDPR. Read more about security and data protection…

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