AllergyIntolerance.recordedDate Description (update) :  Date allergy or intolerance was first recorded Comments (update) :  When onset date is unknown, recordedDate can be used to establish if the allergy or intolerance was present on or before a given date.  If the recordedDate is known and provided by a sending system, it is preferred that the receiving system preserve that recordedDate value. If the recordedDate is not provided by the sending system, the receipt timestamp is sometimes used as the recordedDate.  By contrast, the recorder is the most  recent author .  AllergyIntolerance. recorder Comment (updated) :  Because the recorder takes responsibility for accurately recording information in the record, the recorder is the  most recent  author.  The recorder may or may not be the asserter.  By contrast, the recordedDate is when the allergy or intolerance was  first  recorded