Encounter Lens

The Encounter resources for a patient are deduplicated by date and enriched encounter class. The Encounter class is added by Zus Enrichment and ensures that Encounters are properly categorized as Ambulatory, Inpatient, Emergency, etc.

If we are unable to categorize an Encounter due to a lack of provided codings or other context, we add a label of Unknown. Because those uncategorized encounters generally contain non-patient interactions like med orders, they are not summarized into an encounter lens.

Encounter Lenses include a summary tag for easy identification:

"meta": {  
    "tag": [  
        {  
            "system": "https://zusapi.com/summary",  
            "code": "Common" 
        }  
    ]  
}

You can query for a patient's Encounter Summary Lens resources by filtering on the tag, as shown below:

{{fhir_url}}/Encounter?_tag=https://zusapi.com/summary|Common&patient.identifier=https://zusapi.com/fhir/identifier/universal-id|{{universal_patient_id}}

Data Model

Field	Note
resource.hospitalization.reAdmission	Set to `R` with system `<http://terminology.hl7.org/CodeSystem/v2-0092>` Set for inpatient (IMP) encounters using the CMS Hospital-Wide Readmission (HWR) measure methodology: Index admissions are defined by specialty and exclusion rules. Oncology, rehabilitation, and mental health admissions are excluded. Planned and unplanned readmissions are told apart using CMS terminology mappings. Same-day transfers and planned readmissions aren't counted. Only the first unplanned readmission within 30 days of an index admission is flagged.
resource.hospitalization.admitSource	Zus receives these values directly from Bamboo and Experian. Additionally, Zus enrichment may normalize certain IMP encounter types to `emd` when it detects that the patient was admitted through the ED.
resource.extension with `"url": "https://zusapi.com/lens/extension/aggregatedFrom"`	The Zus aggregated from extension lists the Encounter resources that were used to generate this output resource.
resource.extension with `"url": "https://zusapi.com/lens/extension/highestPrecisionStart"`	The highest precision start extension lists the start time for the encounter as a valueDateTime from the latest aggregated Encounter.
resource.extension with `"url": "https://zusapi.com/lens/extension/highestPrecisionEnd"`	The highest precision end extension lists the end time for the encounter as a valueDateTime from the latest aggregated Encounter.
resource.extension with `"url": "https://zusapi.com/lens/extension/relatedBinaries"`	The related binaries extension lists `Binary` resources linked to the encounter via Provenance.

Here is an example of a mocked Encounter Lens resource:

{
 "resourceType": "Encounter",
 "id": "7bdd-47fa-accf-6e1f2b855555",


 "class": {
   "system": "http://terminology.hl7.org/CodeSystem/v3-ActCode",
   "code": "AMB",
   "display": "ambulatory"
 },
 "status": "finished",
 "subject": {
   "reference": "Patient/8804-4728-95cf-3ab4af655555",
   "type": "Patient"
 },
 "diagnosis": [
   {
     "condition": {
       "reference": "Condition/6a10-4cd0-b377-d2aa13555555"
     }
   }
 ],
 "extension": [
   {
     "extension": [
       {
         "url": "https://zusapi.com/lens/extension/aggregatedFrom",
         "valueReference": {
           "reference": "Encounter/da3f-4b69-9b15-9e3099655555",
           "type": "Encounter"
         }
       },
       {
         "url": "https://zusapi.com/lens/extension/aggregatedFrom",
         "valueReference": {
           "reference": "Encounter/0b43-414e-a925-58b9d1a55555",
           "type": "Encounter"
         }
       },
       {
         "url": "https://zusapi.com/lens/extension/aggregatedFrom",
         "valueReference": {
           "reference": "Encounter/7d22-40e5-a453-5d3a7d055555",
           "type": "Encounter"
         }
       }
     ],
     "url": "https://zusapi.com/lens/extension/aggregatedFrom"
   },
   {
     "url": "https://zusapi.com/lens/id",
     "valueString": "8326-c94e-4fd4-aabe-4fa744655555"
   },
   {
     "url": "https://zusapi.com/fhir/identifier/universal-id",
     "valueString": "7fb1-40ff-8e63-b3f4e0355555"
   }
 ],
 "identifier": [
   {
     "system": "urn:oid:1.2.840.114350.1.13.280.2.7.3.698084.8",
     "value": "1484343255"
   },
   {
     "system": "urn:oid:1.2.840.114350.1.13.280.2.7.3.698084.8",
     "value": "1484345497"
   },
   {
     "system": "urn:oid:1.2.840.114350.1.13.280.2.7.3.698084.8",
     "value": "1484616178"
   }
 ],
 "location": [
   {
     "location": {
       "reference": "Location/5073-74ae-4d80-877d-5c628e055555"
     }
   },
   {
     "location": {
       "reference": "Location/deb-9491-46dc-91f6-46deace55555"
     }
   }
 ],
 "meta": {
   "extension": [
     {
       "url": "https://zusapi.com/stream",
       "valueString": "zus"
     },
     {
       "url": "https://zusapi.com/created-at",
       "valueInstant": "2024-06-25T20:10:17.143+00:00"
     }
   ],
   "versionId": "1",
   "lastUpdated": "2024-06-25T20:10:16.545+00:00",
   "tag": [
     {
       "system": "https://zusapi.com/summary",
       "code": "Common"
     },
     {
       "system": "https://zusapi.com/accesscontrol/owner",
       "code": "builder/bb0b-4543-8489-262fcbf55555"
     }
   ]
 },
 "participant": [
   {
     "individual": {
       "reference": "Practitioner/7-fbf9-44ec-bc65-3b1becf55555"
     }
   },
   {
     "individual": {
       "reference": "Practitioner/ddfe-4be4-8442-1587a1e55555"
     }
   }
 ],
 "period": {
   "start": "2023-11-20T09:51:00-05:00",
   "end": "2023-11-21T16:57:00-05:00"
 }
}

Data Mart Access

Data from Encounter Lenses is available in the following tables in the Zus Relational Data Mart:

lens_encounter
lens_encounter_aggregated_from
lens_encounter_diagnosis
lens_encounter_hospitalization_discharge_disposition
lens_encounter_hospitalization_discharge_disposition_coding
lens_encounter_identifier
lens_encounter_participant
lens_encounter_related_binaries
lens_encounter_type
lens_encounter_type_coding

Read more about these tables in the Data Mart documentation.

Encounter Lens

Data Model

Data Mart Access

Related pages