Vital Records Common Library (VRCL) FHIR Implementation Guide
2.0.0 - STU2 United States of America flag

This page is part of the Vital Records Common Profile Library (v2.0.0: STU2) based on FHIR (HL7® FHIR® Standard) R4. This is the current published version in its permanent home (it will always be available at this URL). For a full list of available versions, see the Directory of published versions

Usage

Local Time

All event times should be recorded as the local time and local time zone where they took place.

Partial Dates and Times

The purpose of the these extensions (ExtensionPartialDateVitalRecords and ExtensionPartialDateTimeVitalRecords) is to be able to express date and datetime values when some components are not known. For some fields reported in vital records, all four components (year, month, day, time) can be reported/absent independently, resulting in combinations that are not supported by a FHIR dateTime (YYYY, YYYY-MM, YYYY-MM-DD, or a full dateTime). The additional combinations supported by these extensions include:

  • YYYY-XX-DD (year & day with no month)
  • XXXX-MM-DD (month & day with no year)
  • XXXX-XX-DD (day only)
  • XXXX-XX-XX (no recorded date)
  • All of the above options with present or missing time

When using these extensions, a value must be specified for each component (e.g., year, month, day), or a missing value code specified. This allows dates where any component is missing to be specified. These extensions SHALL NOT be used to represent partial values that can be represented by the FHIR date and dateTime directly. The value of the field being extended should provide the portion of the date or dateTime value that can be represented by the FHIR data type. For vital records purposes, the content of the PartialDateTime extension will be used and data absent reasons are restricted to unknown and temp-unknown. Other consumers of the data may not be aware of the extensions, and will rely on the value provided. For example, if the date is 2023-XX-01 (the month being unknown), the value of the date should be 2023, and the partialDate extension would represent all three components.

A value of unknown (all 9's) in IJE is equivalent to a component with DataAbsentReason extension with code unknown. See this for an example of both unknown integer values – an unknown month of birth, "99" in IJE – and unknown time value – the time of birth, "9999" in IJE.

A value of blank (all ' ') in IJE is equivalent to a a component with a DataAbsentReason extension with code temp-unknown.

The following table illustrates the appropriate use of a dateTime field with a partial date time extension. xxxx is a dataAbsentReason of 'temp-unknown'. XXXX is a dataAbsentReason of 'unknown'.

FHIR dateTime Partial Date Time Extension Components YYYY-MM-DD TTTT IJE YYYY IJE MM IJE DD IJE TTTT Description
2023 (none) 2023 blank blank blank Correct Usage
2023-12 (none) 2023 12 blank blank Correct Usage. No extension is required because dateTime can express this partial dateTime.
2023-12-23 (none) 2023 12 23 blank Correct Usage. No extension is required because dateTime can express this partial dateTime.
2023-12-23 T13:28:17-05:00 (none) 2023 12 23 1328. (uses local time) Correct usage.
2023-12-23 2023-12-23 XXXX 2023 12 23 9999 Correct Usage. The extension is required to express the unknown components. The dateTime shows what it can.
(none) XXXX-12-23 1828 9999 12 23 1828 Correct usage. The extension is required and the dateTimecannot express any of this date.
(none) XXXX-12-23 1828 9999 12 23 1828 Correct usage. The extension is required and the dateTimecannot express any of this date.
2023 2023-XX-23 XXXX 2023 99 23 9999 Correct Usage. The extension is required to express the unknown components. The dateTime shows what it can.
2023 2023-xx-23 XXXX 2023 blank 23 9999 Correct Usage. The extension is required to express the unknown components. The dateTime shows what it can. The time is unknown, and the month is temporarily unknown.
(none) 2023-12-23 xxxx 2023 12 23 blank Incorrect usage. This date can be expressed as a FHIR dateTime without the extension.
2023-12-23 2023-12-23 xxxx 2023 12 23 blank Incorrect usage. This date can be expressed as a FHIR dateTime without the extension.
(none) 2023-12-23 XXXX 2023 12 23 9999 Incorrect usage. The extension is required because the unknown time component cannot be expressed as a FHIR dateTime. However, the dateTime should reflect 2023-12-23.
(none) 2023-12-23 xxxx 2023 12 23 blank Incorrect usage. The dateTime should be 2023-12-23. No extension is required because this date can be expressed as a FHIR dateTime.

Birth Date and Time

The USCorePatient profile provides a field for capturing the patient's birthdate. Within the vital records use cases, the date and time of birth are needed, as well as the ability to capture partial dates. The date and time of birth should be captured as follows:

City Codes

FHIR addresses support a string value for city. The death record submission requires a 5 digit coded value, so the IG defines an extension ExtensionCityCodeVitalRecords for this purpose. The code should be selected to match the literal content of the city field. As of the date of publication, these codes should be in accordance with the NCHS Instruction Manual Part 8, Vital Records Geographic Classification, 2014.

County Codes

FHIR addresses support a string value for county (district). The death record submission requires a 3 digit coded value, so the IG defines an extension ExtensionDistrictCodeVitalRecords for this purpose. The code should be selected to match the literal content of the district field. As of the date of publication, these codes should be in accordance with the NCHS Instruction Manual Part 8, Vital Records Geographic Classification, 2014.

State Literals

States and jurisdictions are consistently represented using two letter postal codes bound to a string field. The IJE typically represents states using a 2 letter postal code and a separate literal field. Mapping from the 2 letter codes to literals must be provided outside of the VRCL IG, and can leverage the ValueSetStatesTerritoriesAndProvincesVitalRecords.

Country Literals

Countries are consistently represented using two letter postal codes bound to a string field. The IJE typically represents countries using a 2 letter postal code and a separate literal field. Mapping from the 2 letter codes to literals must be provided outside of the VRCL IG, and can leverage the CodeSystemCountryCodeVitalRecords.

Gender

US Core Patient profile conformance requires that gender be provided. A value of 'unknown' will satisfy this requirement. Complete vital record submissions may fail FHIR validation due to lack of a value for gender. There is no IJE field that is mapped to the Patient.gender field.

Handling of Edit Flags

Edit flags supports validation as part of the Jurisdiction to NCHS use case for submission of birth, fetal death, and death records and can be ignored for other use cases. For details on the use of edit flags see the use-case specific FHIR Implementation Guides.