Path
ContactDetail.telecom.ContactPoint.rank
Id
ContactPoint.rank
Type
Cardinality
0 - 1
Definition
Specifies a preferred order in which to use a set of contacts. ContactPoints with lower rank values are more preferred than those with higher rank values.
Comment
Note that rank does not necessarily follow the order in which the contacts are represented in the instance.
Ranks need not be unique. E.g. it's possible to have multiple contacts with rank=1. If the ranks have different systems or uses, this would be interpreted to mean "X is my most preferred phone number, Y is my most preferred email address" or "X is my preferred home email and Y is my preferred work email". If the system and use for equally-ranked contacts are the same, then the level of preference is equivalent for both repetitions.
Ranks need not be sequential and not all repetitions must have a rank. For example, it's possible to have 4 contacts with ranks of 2, 5 and two with no rank specified. That would be interpreted to mean the first is preferred over the second and no preference stated for the remaining contacts.
Constraint
All FHIR elements must have a @value or children