add suggested text to: Implantable medical devices that have UDI information  SHALL  represent this information in either  carrierAIDC  or  carrierHRF . UDI may not be present in all scenarios such as historical implantable devices, patient reported implant information, payer reported devices, or improperly documented implants. If UDI is not present and the manufacturer and model information is available, it  SHOULD  be included to support historical reports of implantable medical devices . Although both are marked must support, servers are not required to support both udi_HRF and udi_AIDC but they SHALL support at least one of these elements