Design how to handle dynamic identifiers based on Value sets for Hep. MMGs

The Hep MMGs have some dynamic mappings based on Value sets.

ex.:

 {
      "id": "3",
      "type": "Single",
      "name": "Contact Type",
      "startingDescription": "START: Contact Type Section ",
      "endingDescription": "END: Contact Type Section ",
      "elements": [
        {
          "name": "Contact Type",
          "description": "During the  2 -6 weeks prior to the onset of symptoms, type of contact the subject had with a person with confirmed or suspected Hepatitis virus infection?(Coded)",
          "dataType": "Coded",
          "codeSystem": "Code System from the value set \"Contact Type (Hepatitis A)\" for INV603 would be used as a data element code system.",
          "legacyPriority": "P",
          "priority": "1",
          "isRepeat": false,
          "mayRepeat": "N",
          "valueSetCode": "PHVS_ContactType_HepatitisA",
          "mappings": {
            "hl7v251": {
              "legacyIdentifier": "INV603",
              "identifier": "Concept Code  from the value set \"Contact Type (Hepatitis A)\" for INV603 would be used as a data element identifier.",
              "messageContext": "OBX segment with\nOBX-3.1=Value from value set",
              "dataType": "CWE",
              "segmentType": "OBX",
              "obrPosition": 1,
              "fieldPosition": 3,
              "componentPosition": 1,
              "usage": "R",
              "cardinality": "[1..1]",
              "literalFieldValues": {},
              "repeatingGroupElementType": "NO",
              "implementationNotes": "Contact Type (INV603) value set concept codes that would come in OBX-3 are listed below.\n\nContact Type Indicator (INV828) would be used as a response in OBX-5.",
            }
          }
        }

What that translates to, is that the message should have one OBX for each Value Set concept.:

OBX|41|CWE|INV602^Contact with Confirmed or Suspected Case^2.16.840.1.114222.4.5.232^INV602^During the 2-6 weeks prior to onset, was patient a contact of a confirmed or suspected case?^L||Y^Yes^2.16.840.1.113883.12.136||||||F
OBX|42|CWE|43018001^Babysitter^2.16.840.1.113883.6.96^INV603_1^Babysitter of This Patient (Contact Type)^L||UNK^Unknown^2.16.840.1.113883.5.1008||||||F
OBX|43|CWE|PHC299^Child cared for by this patient^2.16.840.1.114222.4.5.232^INV603_2^Child Cared For By This Patient (Contact Type)^L||UNK^Unknown^2.16.840.1.113883.5.1008||||||F
OBX|44|CWE|PHC300^Household member (non-sexual)^2.16.840.1.114222.4.5.232^INV603_3^Household Member (Non-Sexual) (Contact Type)^L||N^No^2.16.840.1.113883.12.136||||||F
OBX|45|CWE|PHC301^Playmate^2.16.840.1.114222.4.5.232^INV603_4^Playmate (Contact Type)^L||N^No^2.16.840.1.113883.12.136||||||F
OBX|46|CWE|225517006^Sexual partners^2.16.840.1.113883.6.96^INV603_5^Sex Partner (Contact Type)^L||Y^Yes^2.16.840.1.113883.12.136||||||F
OBX|47|CWE|PHC1304^Other Contact Type^2.16.840.1.114222.4.5.232^INV603_6^Other (Contact Type)^L||UNK^Unknown^2.16.840.1.113883.5.1008||||||F

Currently, MMG Vaidation and Transformation do not understand this. Needs enhancements.

couple of potential solutions:

Solution A

Generate a single element on the MMG for each of the concepts.

Pros:

MMG is immutable - we always validate and transform regardless of changes to PHINVads.
Current Code supports this. (no code changes necessary)

Cons: MMG must be re-generated if Value set changes.

Solution B

Handle this dynamic behavior in the validation / transformation code.

Pros:

Will support future cases where this might happen again.
It automatically handles Value set code changes.

Cons:

Final JSon schema could change if valuset code changes.

Potential schema generation for this:

Option A:

"contact_type": [
    {
        "name": "BABYSITTER",
        "code": "480001",
        "value": {
                "identifier": "UNK",
                "text": "Unknown",
                 "code_system": "PHINVADS"
        }
    },
  {
        "name": "Child cared for by this patient",
        "code": "PCH299",
        "value": {
                "identifier": "Y",
                "text": "Yes",
                 "code_system": "PHINVADS"
        }
    },
...
]

option B: (This applies to Solution A above)

"contact_type_babysitter": {
                "identifier": "UNK",
                "text": "Unknown",
                 "code_system": "PHINVADS"
        }
"contact_type_child_cared_for_by_this_patient": {
                "identifier": "UNK",
                "text": "Unknown",
                 "code_system": "PHINVADS"
        }
...

Option C:

"contact_type": {
    "babysitter": {  "identifier": "UNK",   "text": "Unknown",  "code_system": "PHINVADS" }
    "contact_type_child_cared_for_by_this_patient": {  "identifier": "UNK",   "text": "Unknown",  "code_system": "PHINVADS" }
  .....

CDCgov / data-exchange-hl7

Design how to handle dynamic identifiers based on Value sets for Hep. MMGs #316