Which study visits review subjects' signed informed consent forms?

The correct choice focuses on periodic and termination site visits, which are key moments in a clinical trial where review of participants' signed informed consent forms is essential. During periodic visits, the investigator's team assesses ongoing compliance with study protocols, including ensuring that proper informed consent has been obtained before subjects participate. This helps verify that all subjects are aware of their rights as participants and understand the scope and risks of the study.

At termination site visits, it is crucial to ensure that all consent documentation is in order before closing the trial at the site. This includes checking whether consent forms were signed and that the participants were adequately informed about their involvement in the study.

In contrast, although site initiation and monitoring visits involve oversight of the study and its procedures, they may not specifically emphasize reviewing signed informed consent forms in the same way. Similarly, termination and interim visits would focus more on concluding studies and reviewing interim data rather than the initial consent process. Therefore, periodic and termination site visits are specifically tailored to ensure that the consent process is accurately documented and adhered to throughout the study.