Health Info Processing — FHIR + LOINC/SNOMED

What this is?

One-file, pure JS + JSON demo that mimics FHIR-ish resources and coding. Edit the JSON below and click Run ARC:

Data — FHIR-flavored resources: Patient, Encounter, DocumentReference, Observation, Condition, Consent; lab codes (LOINC), condition codes (SNOMED).
Policies — declarative JSON rules: an array of objects with if atoms (allowing "not": true) ⇒ then atoms, plus an explain template.
Answer — the newly derived facts only (keeps the strongest priority per patient).
Reason Why — mathematical-English derivations based on bound variables per rule firing.
Check — JSON assertions evaluated against the full fact set (… items).
Health Info Summary — per-patient strongest priority and tasks. Priority order: Blocked > High > Normal > Low.

Engine: tiny forward-chainer with unification, subclassing (subClass), transitive partOf, observation→patient mapping, and negation-as-failure for "not": true.

Data (JSON)

{
  "classes": [
    "Patient","Encounter","DocumentReference","Observation","Condition","Consent","Component",
    "ObservationClass","ClinicalIssue","PrivacyIssue","DataQualityIssue","WorkflowEvent",
    "ShareRequested",
    "Task","Priority","Blocked","High","Normal","Low"
  ],

"subclassOf": [
    ["Encounter","Component"], ["DocumentReference","Component"],
    ["ObservationClass","Observation"],
    ["ShareRequested","WorkflowEvent"],
    ["PrivacyIssue","Observation"], ["DataQualityIssue","Observation"], ["ClinicalIssue","Observation"], ["WorkflowEvent","Observation"]
  ],

"assets": {
    "P1":  {"type":"Patient"},
    "Enc1":{"type":"Encounter","partOf":"P1"},
    "Note1":{"type":"DocumentReference","partOf":"Enc1"},

"P2":  {"type":"Patient"},
    "Enc2":{"type":"Encounter","partOf":"P2"},
    "Note2":{"type":"DocumentReference","partOf":"Enc2"}
  },

"consents": [
    {"id":"C1","type":"Consent","partOf":"P1","scope":"treatment","status":"active"},
    {"id":"C3","type":"Consent","partOf":"P2","scope":"research","status":"active","permittedOrg":"OrgR1"}
  ],

"conditions": [
    {"id":"CondDM2","type":"Condition","partOf":"P2","codeSystem":"unknown","code":"E11"}
  ],

"observations": [
    {"id":"ObsPHI1","type":"PrivacyIssue","about":"Note1","codeSystem":"custom","code":"PHIInNote"},
    {"id":"SR1","type":"ShareRequested","about":"P1","sharePurpose":"treatment","shareOrg":"OrgH1"},
    {"id":"ObsHb1","type":"Observation","about":"Enc1","codeSystem":"loinc","code":"718-7","category":"laboratory","valueFlag":"criticalLow"},
    {"id":"ObsCovid1","type":"Observation","about":"Enc1","codeSystem":"loinc","code":"94531-1","category":"laboratory","valueFlag":"positive"},

{"id":"SR2","type":"ShareRequested","about":"P2","sharePurpose":"research","shareOrg":"OrgR1"},
    {"id":"ObsUnknownLab2","type":"Observation","about":"Enc2","codeSystem":"unknown","code":"X123","category":"laboratory"},
    {"id":"ObsPHI2","type":"PrivacyIssue","about":"Note2","codeSystem":"custom","code":"PHIInNote"}
  ]
}

Policies (declarative JSON rules)

[
  { "id":"R1-Subclass",
    "if":[{"pred":"subClass","s":"?A","o":"?B"},{"pred":"isA","s":"?S","o":"?A"}],
    "then":[{"pred":"isA","s":"?S","o":"?B"}],
    "explain":"Since ?A ⊑ ?B and ?S ∈ ?A, infer ?S ∈ ?B."
  },
  { "id":"R2-PartOfTransitive",
    "if":[{"pred":"partOf","s":"?x","o":"?y"},{"pred":"partOf","s":"?y","o":"?z"}],
    "then":[{"pred":"partOf","s":"?x","o":"?z"}],
    "explain":"Because ?x is part of ?y and ?y is part of ?z, ?x is part of ?z."
  },
  { "id":"R3-ObsToPatient",
    "if":[{"pred":"about","s":"?obs","o":"?comp"},{"pred":"partOf","s":"?comp","o":"?P"}],
    "then":[{"pred":"aboutPatient","s":"?obs","o":"?P"}],
    "explain":"Observation ?obs concerns component ?comp of patient ?P; thus aboutPatient(?obs,?P)."
  },

{ "id":"R4-ConsentToPatient",
    "if":[{"pred":"isA","s":"?C","o":"Consent"},{"pred":"partOf","s":"?C","o":"?P"}],
    "then":[{"pred":"consentOfPatient","s":"?C","o":"?P"}],
    "explain":"Consent ?C belongs to patient ?P."
  },

{ "id":"R5-ActiveResearchConsent-Org",
    "if":[{"pred":"isA","s":"?C","o":"Consent"},{"pred":"consentOfPatient","s":"?C","o":"?P"},
          {"pred":"consentScope","s":"?C","o":"research"},{"pred":"consentStatus","s":"?C","o":"active"},
          {"pred":"consentPermittedOrg","s":"?C","o":"?Org"}],
    "then":[{"pred":"hasActiveResearchConsentFor","s":"?P","o":"?Org"}],
    "explain":"?P has an active research consent permitting org ?Org."
  },
  { "id":"R6-ActiveResearchConsent-AnyOrg",
    "if":[{"pred":"isA","s":"?C","o":"Consent"},{"pred":"consentOfPatient","s":"?C","o":"?P"},
          {"pred":"consentScope","s":"?C","o":"research"},{"pred":"consentStatus","s":"?C","o":"active"},
          {"not":true,"pred":"consentPermittedOrg","s":"?C","o":"?x"}],
    "then":[{"pred":"hasActiveResearchConsentFor","s":"?P","o":"ANY"}],
    "explain":"?P has an active research consent without org restriction."
  },
  { "id":"R7-ActiveTreatmentConsent",
    "if":[{"pred":"isA","s":"?C","o":"Consent"},{"pred":"consentOfPatient","s":"?C","o":"?P"},
          {"pred":"consentScope","s":"?C","o":"treatment"},{"pred":"consentStatus","s":"?C","o":"active"}],
    "then":[{"pred":"hasActiveTreatmentConsent","s":"?P","o":"yes"}],
    "explain":"?P has an active treatment consent."
  },

{ "id":"C-PHI-Handling",
    "if":[{"pred":"isA","s":"?obs","o":"PrivacyIssue"},{"pred":"aboutPatient","s":"?obs","o":"?P"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"DeidentifyText"}],
    "explain":"PHI present for ?P requires de-identification."
  },

{ "id":"Share-Research-Allow-Org",
    "if":[{"pred":"isA","s":"?sr","o":"ShareRequested"},{"pred":"aboutPatient","s":"?sr","o":"?P"},
          {"pred":"sharePurpose","s":"?sr","o":"research"},{"pred":"shareOrg","s":"?sr","o":"?Org"},
          {"pred":"hasActiveResearchConsentFor","s":"?P","o":"?Org"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"AllowResearchShare"},{"pred":"priority","s":"?P","o":"Normal"}],
    "explain":"Research share for ?P allowed via matching active consent to org ?Org."
  },
  { "id":"Share-Research-Allow-Any",
    "if":[{"pred":"isA","s":"?sr","o":"ShareRequested"},{"pred":"aboutPatient","s":"?sr","o":"?P"},
          {"pred":"sharePurpose","s":"?sr","o":"research"},{"pred":"shareOrg","s":"?sr","o":"?Org"},
          {"pred":"hasActiveResearchConsentFor","s":"?P","o":"ANY"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"AllowResearchShare"},{"pred":"priority","s":"?P","o":"Normal"}],
    "explain":"Research share for ?P allowed by active consent without org restriction."
  },
  { "id":"Share-Research-Block",
    "if":[{"pred":"isA","s":"?sr","o":"ShareRequested"},{"pred":"aboutPatient","s":"?sr","o":"?P"},
          {"pred":"sharePurpose","s":"?sr","o":"research"},{"pred":"shareOrg","s":"?sr","o":"?Org"},
          {"not":true,"pred":"hasActiveResearchConsentFor","s":"?P","o":"?Org"},
          {"not":true,"pred":"hasActiveResearchConsentFor","s":"?P","o":"ANY"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"ObtainResearchConsent"},{"pred":"priority","s":"?P","o":"Blocked"}],
    "explain":"Research share for ?P is blocked: no suitable active research consent."
  },

{ "id":"Share-Treatment-Allow",
    "if":[{"pred":"isA","s":"?sr","o":"ShareRequested"},{"pred":"aboutPatient","s":"?sr","o":"?P"},
          {"pred":"sharePurpose","s":"?sr","o":"treatment"},{"pred":"hasActiveTreatmentConsent","s":"?P","o":"yes"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"AllowTreatmentShare"},{"pred":"priority","s":"?P","o":"Normal"}],
    "explain":"Treatment share for ?P allowed by active consent."
  },
  { "id":"Share-Treatment-Block",
    "if":[{"pred":"isA","s":"?sr","o":"ShareRequested"},{"pred":"aboutPatient","s":"?sr","o":"?P"},
          {"pred":"sharePurpose","s":"?sr","o":"treatment"},
          {"not":true,"pred":"hasActiveTreatmentConsent","s":"?P","o":"yes"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"ObtainTreatmentConsent"},{"pred":"priority","s":"?P","o":"Blocked"}],
    "explain":"Treatment share for ?P is blocked: no active treatment consent."
  },

{ "id":"Map-UnknownLab→LOINC",
    "if":[{"pred":"isA","s":"?obs","o":"Observation"},{"pred":"aboutPatient","s":"?obs","o":"?P"},
          {"pred":"category","s":"?obs","o":"laboratory"},{"pred":"codeSystem","s":"?obs","o":"unknown"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"MapToLOINC"}],
    "explain":"Lab observation for ?P has unknown coding; map to LOINC."
  },
  { "id":"Map-UnknownCondition→SNOMED",
    "if":[{"pred":"isA","s":"?cond","o":"Condition"},{"pred":"partOf","s":"?cond","o":"?P"},
          {"pred":"codeSystem","s":"?cond","o":"unknown"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"MapToSNOMED"}],
    "explain":"Condition for ?P has unknown code; map to SNOMED CT."
  },

{ "id":"Clinical-COVIDPCR-Positive",
    "if":[{"pred":"isA","s":"?obs","o":"Observation"},{"pred":"aboutPatient","s":"?obs","o":"?P"},
          {"pred":"codeSystem","s":"?obs","o":"loinc"},{"pred":"code","s":"?obs","o":"94531-1"},
          {"pred":"valueFlag","s":"?obs","o":"positive"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"IsolatePatient"},
            {"pred":"requiresTask","s":"?P","o":"NotifyPublicHealth"},
            {"pred":"priority","s":"?P","o":"High"}],
    "explain":"LOINC 94531-1 is positive for ?P → isolation, public health notification (High)."
  },
  { "id":"Clinical-Hb-CriticalLow",
    "if":[{"pred":"isA","s":"?obs","o":"Observation"},{"pred":"aboutPatient","s":"?obs","o":"?P"},
          {"pred":"codeSystem","s":"?obs","o":"loinc"},{"pred":"code","s":"?obs","o":"718-7"},
          {"pred":"valueFlag","s":"?obs","o":"criticalLow"}],
    "then":[{"pred":"requiresTask","s":"?P","o":"UrgentTransfusionConsult"},
            {"pred":"priority","s":"?P","o":"High"}],
    "explain":"LOINC 718-7 critical low for ?P → urgent transfusion consult (High)."
  },

{ "id":"P-Default-Normal",
    "if":[{"pred":"requiresTask","s":"?P","o":"?X"},
          {"not":true,"pred":"priority","s":"?P","o":"?Any"}],
    "then":[{"pred":"priority","s":"?P","o":"Normal"}],
    "explain":"If ?P has tasks but no priority, default to Normal."
  }
]

Checks 0

[
  {"name":"PHI in Note1 → about P1",                 "pattern":{"pred":"aboutPatient","s":"ObsPHI1","o":"P1"}},
  {"name":"SR1 (treatment) → about P1",              "pattern":{"pred":"aboutPatient","s":"SR1","o":"P1"}},
  {"name":"P1 has active treatment consent",         "pattern":{"pred":"hasActiveTreatmentConsent","s":"P1","o":"yes"}},
  {"name":"Allow treatment share for P1",            "pattern":{"pred":"requiresTask","s":"P1","o":"AllowTreatmentShare"}},
  {"name":"P1 priority High (labs)",                 "pattern":{"pred":"priority","s":"P1","o":"High"}},
  {"name":"P1 needs UrgentTransfusionConsult",       "pattern":{"pred":"requiresTask","s":"P1","o":"UrgentTransfusionConsult"}},
  {"name":"P1 needs Isolation (COVID+)",             "pattern":{"pred":"requiresTask","s":"P1","o":"IsolatePatient"}},
  {"name":"P1 notify public health",                 "pattern":{"pred":"requiresTask","s":"P1","o":"NotifyPublicHealth"}},
  {"name":"P2 has active research consent for OrgR1","pattern":{"pred":"hasActiveResearchConsentFor","s":"P2","o":"OrgR1"}},
  {"name":"Allow research share for P2",             "pattern":{"pred":"requiresTask","s":"P2","o":"AllowResearchShare"}},
  {"name":"P2 map unknown lab to LOINC",             "pattern":{"pred":"requiresTask","s":"P2","o":"MapToLOINC"}},
  {"name":"P2 map unknown condition to SNOMED",      "pattern":{"pred":"requiresTask","s":"P2","o":"MapToSNOMED"}},
  {"name":"P2 deidentify text",                      "pattern":{"pred":"requiresTask","s":"P2","o":"DeidentifyText"}},
  {"name":"P2 priority Normal",                      "pattern":{"pred":"priority","s":"P2","o":"Normal"}}
]

Controls

Answer (newly derived facts)

computing…

Reason Why (mathematical English)

(click “Run ARC”)

Check

computing…

Health Info Summary

(run to populate)