The PI is ultimately responsible for ensuring that informed consent is obtained (see 21 CFR 812.100) and the general expectation is that the PI will ensure that the person(s) conducting informed consent is appropriately qualified to lead the discussion. This means they are able to explain the research, facilitate understanding by the participant, and answer any study related questions. This may or may not be a study physician, another study medical provider, or a study coordinator and it may be one person or several persons. That said, it would generally be expected that a study coordinator would not present a complex study involving significant medical risk without at least partial involvement of a medical provider (Likely the PI), but not that a medical provider must lead the entire discussion.
