QuestionnaireResponse.age_at_response duplicates Visit.age_at_visit_start linked through QuestionnaireResponse.associated_visit

[diatomsRcool]

Does QuestionnaireResponse.age_at_response duplicate Visit.age_at_visit_start because these are linked through QuestionnaireResponse.associated_visit?

[bfurner]

Currently QuestionnaireResponse.associated_visit is an optional attribute to handle the potential use case of questionnaires administered outside of an obviously associated visit. Also, it is conceivable that a visit spans numerous days (e.g. an inpatient stay) and that a questionnaire may be administered on one day of a multiple-day visit and one wants to be able to track on which particular day a response is given. In either of these use cases, having the ability to provide an QuestionnaireResponse.age_at_response would be useful.