What is a forced randomisation?
When a trial uses a code list then it is possible that a kit matching the chosen treatment group may not be available on site. This is more likely to happen when the drug supply is constrained so that each site does not hold much IMP stock.
When this happens there are several possible outcomes:
- The randomisation fails
- The randomisation succeeds but no kit code is assigned
- A different treatment group is chosen (one which is available on site)
The last case this is called a
forced randomisation because the first choice treatment allocation was not available.
Sealed Envelope randomisation supports forced randomisation when using
minimisation. It can be specified on the
code list tab of the CRF Builder. You can see whether forced allocations are allowed for your trial on the
specification page. If an allocation is forced both the original and forced allocation is recorded in the randomisation database.