Encounter

An encounter in StudyTRAX is a contact with a subject, typically a visit.   An encounter can be a fixed encounter used for data collection whose schedule is known (e.g. Baseline, Month 1, Month 6).  A subject can only have one occurence of a specified fixed encounter. An encounter can also be a non-fixed encounter used for data collection with an unknown schedule (e.g. tracking rejection episodes after a transplant, an unscheduled visit).  A subject may never have a non-fixed encounter or may have mulitple occurences of a specified non-fixed encounter.