Dear allstaters and experts in randomization,
Please advise on the following two scenario in a randomized trial to what issues should be considered:
First scenario-
During randomization visit, an eligible participant is given a randomization envelop containing the details of the treatment (implant device) she would be allocated to. This participant changes her mind (refusing to participate) right after opening the envelop (she may have read what treatment she is assigned) and she never received any treatment.
The trial investigator gives this same opened randomization envelop to the next participant who is coming for randomization. this second participant received the actual treatment (intended for the previous particip.) and continues her follow-up and the problem about randomization irregularieties is only discovered later during follow-up.
Question: Can we say participant 1 was discontinued before randomization since she never actually received any treatment?
What about participant 2, should she be excluded from analysis because the investigators knew the treatment she was going to receive prior to randomization contrary to the protocol?
Second scenario-
two participants are each given an envelop containing one of two treatment (implant devices) randomly allocated to them. Accidentally the actual treatments are switched, so that each of the two participants despite being assigned one treatment, she actually receive the one intended for the other. this problem is discovered later on during followup.
Question: Can they be kept in the analysis and analysed according to intention to treat? Are there ethical issues to be considered, as they did not receive the treatments they thought they were on?
I'd appreciate any responses,
Thanks
Dr Habib.
