Regarding randomization and unblinding, which statement is correct?

Regarding randomization and unblinding, which statement is correct?

• A. The investigator should follow the trial's randomization procedures and ensure that the code is broken only in accordance with the protocol. If blinded, promptly document and explain any premature unblinding to the sponsor.
• B. The investigator may break the code at will.
• C. The sponsor decides randomization, not the investigator.
• D. Unblinding is not allowed at all.

Answer: (A)

The important idea is that randomization and blinding are protected throughout the trial, and any deviation from that protection must follow the protocol and proper channels. The investigator is responsible for following the trial’s randomization procedures and keeping the allocation concealed unless the protocol or safety needs require unblinding. If unblinding occurs while the study is blinded, it should be documented promptly and explained to the sponsor (and, as required, to the appropriate oversight bodies) so there is a clear record and no bias is introduced. This is why the correct statement stands: the investigator follows the randomization procedures, and if unblinding happens prematurely, a prompt, documented explanation to the sponsor is required. Unauthorised or at-will unblinding would undermine the trial’s integrity, and saying the sponsor alone decides randomization or that unblinding is never allowed contradicts standard safety and protocol provisions.

The important idea is that randomization and blinding are protected throughout the trial, and any deviation from that protection must follow the protocol and proper channels. The investigator is responsible for following the trial’s randomization procedures and keeping the allocation concealed unless the protocol or safety needs require unblinding. If unblinding occurs while the study is blinded, it should be documented promptly and explained to the sponsor (and, as required, to the appropriate oversight bodies) so there is a clear record and no bias is introduced.

This is why the correct statement stands: the investigator follows the randomization procedures, and if unblinding happens prematurely, a prompt, documented explanation to the sponsor is required. Unauthorised or at-will unblinding would undermine the trial’s integrity, and saying the sponsor alone decides randomization or that unblinding is never allowed contradicts standard safety and protocol provisions.