If your trial is blinded a randomisation list (or code list) will be used to link randomisation codes to treatments.
When a patient is randomised, a randomisation code is assigned from this list. Only people who have access to the list know what treatment this code is linked to. Normally the only people who have access to the list are:
| Randomisation code | Treatment |
|---|---|
| AF5 | Active |
| GY6 | Placebo |
| YU1 | Active |
| FT2 | Placebo |
Codes are written or printed on the packaging of drugs you give to trial patients. This is usually done either by the trial pharmacies or a specialist drug packaging company. Obviously these parties will need to be unblinded and require a copy of the randomisation list to do this.
If you use a drug packaging company you will need to allocate different parts of the code list to different trial sites. You will need to update the randomisation system with this information to ensure the code allocated is available on site when randomising a patient. Conversely, if pharmacies hold unblinded stocks of the trial drugs a pharmacist can write the randomisation code on the packaging. In this case there is no need to allocate different parts of the code list to different trial sites.
The randomisation list can be created by your own statistician or by Sealed Envelope. In the former case please send the randomisation list to us as a spreadsheet or CSV file.
The randomisation code can be any format - it can be a simple number (1, 2, 3…), a box/pack number (2000/21) or an alphanumeric code (AF3, TY8) as above. Some issues to bear in mind when devising a format are:
| Randomisation code | Treatment |
|---|---|
| 1 | Active |
| 2 | Active |
| 3 | Active |
| 4 | Active |
| 5 | Placebo |
If you are using our comprehensive randomisation service, we customise the randomisation form for your trial. The fields to include on this form would normally include:
There may be rare occasions when you cannot access Sealed Envelope, either because of an issue with your internet access or down-time at Sealed Envelope. The trial coordinating centre should be prepared for this event and have a back-up procedure in place. This will usually be described in a randomisation SOP. Common strategies are:
The appropriate strategies will vary by trial. If a manual randomisation is performed, an administrator account can be used to update the randomisation system when it becomes available again.
When a trial uses a code list and a dynamic method of allocation such as minimisation then occasionally the treatment group chosen 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 trial drug stock.
When this happens one of two things can happen:
In the latter case this is called a forced randomisation because the first choice treatment allocation was not available.
Sealed Envelope randomisation systems support both outcomes. You can see whether forced allocations are allowed for your trial on the specification page. If an allocation is forced it is recorded in the randomisation database.
Read about the problems of using real envelopes.
First check that you are trying to log in to the correct system. If you have an email with your login details from Sealed Envelope the URL of the system concerned will be present in the email. In particular be aware that test systems and live system are different and do not share the same login information.
If you are trying to use the password given in an email to you, and you have not changed it since the email was sent, then make sure you are typing in the password exactly as shown. Some letters and digits may look similar (e.g. ‘0’ and ‘O’, ‘1’ and ‘l’). You may find it easier to copy and paste the password, but if you do, make sure you don’t accidentally include leading or trailing spaces.
If you have changed your password or PIN and cannot remember it anymore, ask the trial manager to reset it for you.
You must contact the trial manager or other holder of an administrator account for the system concerned. They will be able to reset your password. An email containing your new password and PIN will be sent to the email address for your account.
When a randomisation system is set up, the first administrator account is created by Sealed Envelope and the login details are sent to that person’s email address. The administrator should log in and create the trial sites, unless the sites have been pre-coded by Sealed Envelope.
You do not need to add all your sites at once - you can come back later and add more sites as needed.
Next you should add some investigator accounts for each site so that randomisations can be performed by the sites. You do this through the user manager.
If your trial has a code list and/or rescue list you should update the list to reflect the availability of treatment kits at each site. Randomisation cannot occur if there are no codes available at a site.
Finally check the specification page and randomisation form and report any discrepancies or errors to Sealed Envelope.
When your randomisation system is set up in Sealed Envelope’s evaluation environment, you should test it until you are satisfied it meets your requirements and is randomising as expected.
The test system is an identical copy of the live randomisation system except it will use a dummy randomisation list or code list (where appropriate). To test it, we recommend taking the following steps:
Notification emails are sent out from our servers when randomisations take place or for various other events. Sometimes a recipient doesn’t receive the email. There are several reasons for this which in descending order of likelihood are:
nhs.uk addresses.Unfortunately we cannot resend notifications so if your mail administrator cannot find it your only option is to ask someone else who received the same notification to forward a copy to you.