recorder - remove reference to ResearchSubject participant.actor - remove reference to ResearchSubject causality.author - remove reference to ResearchSubject Add a comment to participant.actor to say:  "The subject can be a participant if the subject was involved in the adverse event in another capacity beyond just being the subject, such as when the subject is a contributor or informant." Add a comment to participant backbone to say:  "The participant should not be used when there is another element to capture the participation, such as subject or recorder"