Set up (double) blinded randomization
- It is possible to set up blinded randomization in Castor by assigning appropriate rights to users
- There are two separate user rights that are linked to randomization: ‘Randomize’ (Rand.) and ‘View Randomization’ (View rand.).
- Each of these rights can be assigned to different users and institutes.
- With the Randomize right, a user can randomize patients (records).
- This is done via the Randomization tab within a record.
- The View Randomization right is necessary to see to which group a record has been allocated.
- The user with Randomize rights only will see the date of randomization and by whom the randomization was performed, but the allocation and randomization number will remain hidden.
- This means that users who need to be blinded to the group allocation should not have View Randomization rights.
- To unblind the randomization, assign the View Randomization right to the user who needs unblinding at the end of the study.
- In my study, the user will not be able to see the randomization allocation for the Test Institute.
- This is captured in the audit trail.
- Make sure that the forms are also built to preserve the blinding.
- There should be no questions that are dependent on the randomization group, nor should the outcome of randomization be used in a calculation or summary field.
- The randomization field in your study will indicate 'Hidden' for users without View Randomization rights.