When a search parameter points to a choice type, not all of the available data types may be relevant for the type of search parameter.

For example: Procedure-date, with type "date", has the expression "Procedure.occurrence". This field can be a dateTime, Period, string, Age, Range, or Timing (Timing was added after R4). From the search parameters page, it looks like only dateTime, Period, and Timing are eligible for a date search. This search parameter's expression should be clarified to "Procedure.occurrence.as(dateTime) | Procedure.occurrence.as(Period) | Procedure.occurrence.as(Timing)".

Search parameters should be reviewed for other instances of this pattern.