Observation

Clinical Tests / Laboratory / Smoking Status / Vital Signs : USCDI v1 - This describes and provides measurements or simple assertions. Most observations are simple name/value pair assertions but some observations, such as blood pressure, pulse oximetry, group other observations together logically. Examples of common observations are: Laboratory results (blood sugar, hemoglobin), Vital signs (temperature, blood pressure), Personal characteristics (height, weight), and Social history (tobacco/alcohol use, employment status). Pathology reports, radiology reports, and other textual reports should be represented by the DiagnosticReport resource.

Request Parameters

The following fields and datatypes are the parameters for the request string. All fields are optional, however if no settings are set, all values will be exported up to the maximum count of 100

Name (type) Description (bindings)
_id
(token)
A single or comma separated list of Observation ids. It is a required field if the patient field is not given.
patient
(reference)
Who the observation is for. It is a required field if the _id field is not given.
_count
(number)
The maximum number of results to return in a page. Not honored when '_id' is set.
date
(date)
A date or date range from which to find observation. The 'date' parameter may be provided once without a prefix or time component to imply a date range or once without a prefix and with a time component to search for observation at a specific time. Alternately it may be provided twice with 'le' and 'gt' prefixes to search for observation within a specific range. The date prefix pair must create a closed range.
status
(token)
The overall status of the observation.
_pretty
(boolean)
set to false to disable formatted output.
_revinclude
(static)
_revinclude parameter may be provided once with the value Provenance:target to pull the relevant Provenance information. Example: _revinclude=Provenance:target
category
(token)
A single or comma separated list of classifications of the type of observation.
code
(token)
A single or comma separated list of observation types.

Returned Data Fields

The following fields and bindings are returned if valued

Field (type) Description (bindings) Opt?
id
(Id)
Id
status
()
Status

Observation Status Codes (http://hl7.org/fhir/observation-status)
category
(CodeableConcept)
Category (laboratory, social history, vital-signs)

Observation Category Codes (http://terminology.hl7.org/CodeSystem/observation-category)
code
(CodeableConcept)
Code (Observation name or text)

LOINC (http://loinc.org)
SNOMED CT (http://snomed.info/sct)
subject
(Reference)
Subject (Patient)
encounter
(Reference)
Encounter
effective
(DateTime)
Effective date/time (collection date/time for laboratory)
issued
(DateTime)
Issued (date/time observation made available, entered, verified)
value
(CodeableConcept|String|Quantity)
Observation value or result
unit
(String)
Quantity units
dataAbsentReason
(CodeableConcept)
Data absent reason

data absentreason (http://terminology.hl7.org/CodeSystem/data-absent-reason)
Y
referenceRange
(Range)
Reference Range
Y
referenceRange.low
(Quantity)
Reference low
Y
referenceRange.high
(Quantity)
Reference high
Y
referenceRange.text
(String)
Reference text
Y
component
(CodeableConcept)
Component (eg: systolic and diastolic for blood pressure, o2 saturation for pulse ox)

Default Patient Query

The following are live queries representative of a data request on our sandbox environment.

Headers

Accept: application/fhir+json
Authorization: <OAuth2 Bearer Token>

Request

GET https://portal.viewmymed.com/fhir/Observation?patient=99999.122753-00&_count=1

HTTP/1.0 200 OK
Cache-Control: no-cache, private
Content-Type:  application/fhir+json
Date:          Mon, 02 Feb 2026 13:37:44 GMT
Etag:          W/"1"

{
    "resourceType": "Bundle",
    "id": "6980a8a81f8f56980a8a81f8f7",
    "type": "searchset",
    "link": [
        {
            "relation": "self",
            "url": "https://portal.viewmymed.com/api/Observation"
        }
    ],
    "entry": [
        {
            "fullUrl": "https://portal.viewmymed.com/fhir/Observation/48318143469680ec75d721089e818107",
            "resource": {
                "resourceType": "Observation",
                "id": "87cf5fa3bc9a614aa7b6ddf19cbd33eb",
                "meta": {
                    "versionId": "48318143469680ec75d721089e818107",
                    "lastUpdated": "2023-01-26T06:33:04+00:00"
                },
                "text": {
                    "status": "generated",
                    "div": "
// - Tobacco smoking status :
" }, "status": "final", "category": [ { "coding": [ { "system": "http://terminology.hl7.org/CodeSystem/observation-category", "code": "social-history", "display": "Social history" } ], "text": "Social history" } ], "subject": { "reference": "Patient/99997.122753-00" }, "encounter": { "reference": "Encounter/fb9f088c689044da7a617c6ae144be05" }, "effectiveDateTime": "1970-01-01T00:00:00+00:00", "issued": "2023-01-20T15:27:53+00:00", "code": { "coding": [ { "system": "http://loinc.org", "code": "72166-2", "display": "Tobacco smoking status" } ], "text": "Tobacco smoking status" }, "valueCodeableConcept": { "coding": [ { "system": "http://snomed.info/sct", "code": "266919005", "display": "Never Smoked" } ], "text": "Never Smoked" } } } ] }

Error Codes / Outcomes

All endpoints share the same error codes and common outcomes.