How to handle EAV variable/value pairs in MEASUREMENT or OBSERVATION - Call for input from the community

They are Observations when we don’t have an exact-ish (few exceptions) start date or the date represents the day the fact was recorded. All facts you want to know happened for inclusion/exclusion criteria for a study, but can’t be certain of the date for the traditional cause/effect, before/after observational study. Examples: family history, most medical/surgical history, social history, survey data, etc.