All result/observation data would be associated with the Patient resource rather than ResearchSubject. The meaning of data obtained from subjects within a study derives from its context within the study design.

• Should data on a ResearchSubject link to that structure
  • The structure itself likely belongs to ResearchStudy
• Is this handled through Patient

Not sure if a change is needed. If it can all be handled through Patient would suggest illustrations of how this is done should be available and/or connectathon activity to test it out.