Question: UnitID and UnitType in CDA
Jan 15, 2013Question:
What is the purpose of unitID and unitType in the address type in HL7 CDA? Do they come from a closed termset? I assume they are related, but I can’t really tell as I haven’t found documentation about it
Answer:
Well, this is some thing that’s a little unclear in the data types definitions. The data types spec says that these two names map to two particular part type codes:
| unitID | UNID |
| unitType | UNIT |
Then it gives these definitions for these two codes:
| UNID | unit identifier | The number or name of a specific unit contained within a building or complex, as assigned by that building or complex. |
| UNIT | unit designator | Indicates the type of specific unit contained within a building or complex. E.g. Appartment, Floor |
Separating out these kind of fields in an address is very unusual - most systems simply have lines + town/suburb + post code + state/country, depending on where you are in the world.
But some systems parse the address more aggressively, or demand more careful entry on the part of the person filling out the field. In Australia, this level of data entry is something I’ve occasionally seen on that part of large public-facing entities, such as telstra, or medical insurers (as much as anything else, it’s about cheaper postal delivery).
By the way, if you receive an address part UnitId and UnitType, and you don’t cater for these kind of address parts, the intention is that you collapse these to a plain line of text, or something simpler that you do support.