GET Condition

Overview

The Condition API can be used to interact with Condition records for a patient. When querying for data it must always be in the context of a single patient.

• Retrieving or searching for Condition records is performed using a HTTP GET described below.

Condition Retrieval

id and _id

The Condition resource can be retrieved directly if the id of the resource is known. By appending the id to the url will cause the Condition resource to be retrieved. Unlike all other retrieval queries, the response will be a single resource as opposed to a Bundle.

GET /Condition/{id}

An alternate method for retrieval is to make use of the _id search parameter. In this case, the result will be a Bundle. If the id is present the Bundle will contain a single Condition resource, otherwise, the Bundle will be empty.

GET /Condition?_id={id}

Query Parameters

Unless retrieving a Condition resource by the use of id the subject must always be present. The Condition can only be targeted against a single patient at any one time.

Subject

GET /Condition?patient=Patient/{id}

When searching for NHS Numbers use the system https://fhir.nhs.uk/Id/nhs-number. For example:

GET /Condition?patient.identifier=https://fhir.nhs.uk/Id/nhs-number|1234567890

All the search examples shown below will accept the patient parameter in either form.

Code

When searching for Conditions with a specific code the query can be constructed using different combinations of the code system and the code value.

GET /Condition?patient=[value]&code=[code]
GET /Condition?patient=[value]&code=[system]|[code]
GET /Condition?patient=[value]&code=|[code]
GET /Condition?patient=[value]&code=[system]|

For example to search for a Condition of Chronic heart disease using SNOMED then a query would look like the following:

GET /Condition?patient=[value]&code=http://snomed.info/sct|128238001

tip

For further information consult the FHIR specification at http://hl7.org/fhir/STU3/search.html#token

In addition to searching for Conditions with single codes, it is possible to construct a search using a predefined ValueSet that defines a collection of codes.

GET /Condition?patient=[value]&code:in=[ValueSet url]

note

The ValueSets that are available for this function will evolve over time. Speak to Graphnet if you intend to use this capability.

Onset Date

To search on the date of onset of a Condition the following search constructs can be used.

GET /Condition?patient=[value]&onset-date=[value]

To improve searching the API supports the use of search modifiers. The modifiers supported for date are as below:

Modifier	Description
lt	Returns dates less than the search term
le	Returns dates less than or equal to the search term
gt	Returns dates greater than the search term
ge	Returns dates greater than or equal to the search term
eq	Returns dates equal to the search term

GET /Condition?patient=[value]&onset-date=lt[value]
GET /Condition?patient=[value]&onset-date=le[value]
GET /Condition?patient=[value]&onset-date=gt[value]
GET /Condition?patient=[value]&onset-date=ge[value]
GET /Condition?patient=[value]&onset-date=eq[value]

So to search for a Condition with an onset date of 23rd January 2021 the query would be:

GET /Condition?patient=[value]&onset-date=2021-01-23

To search for all Conditions with an onset date before the 23rd December 2020 the query would be:

GET /Condition?patient=[value]&onset-date=lt2020-12-23

tip

For more information on using FHIR search modifiers for dates, take a look at the FHIR STU3 standard at http://hl7.org/fhir/STU3/search.html#date

Asserted Date

To search on the date a Condition was asserted the following search constructs can be used.

GET /Condition?patient=[value]&asserted-date=[value]

To improve searching the API supports the use of search modifiers. The modifiers supported for date are as below:

Modifier	Description
lt	Returns dates less than the search term
le	Returns dates less than or equal to the search term
gt	Returns dates greater than the search term
ge	Returns dates greater than or equal to the search term
eq	Returns dates equal to the search term

GET /Condition?patient=[value]&asserted-date=lt[value]
GET /Condition?patient=[value]&asserted-date=le[value]
GET /Condition?patient=[value]&asserted-date=gt[value]
GET /Condition?patient=[value]&asserted-date=ge[value]
GET /Condition?patient=[value]&asserted-date=eq[value]

So to search for a Condition with an asserted date of 23rd January 2021 the query would be:

GET /Condition?patient=[value]&asserted-date=2021-01-23

To search for all Conditions with an asserted date before the 23rd December 2020 the query would be:

GET /Condition?patient=[value]&asserted-date=lt2020-12-23

tip

For more information on using FHIR search modifiers for dates, take a look at the FHIR STU3 standard at http://hl7.org/fhir/STU3/search.html#date

Identifiers

To search for Conditions using identifiers present on the Condition record, the following search constructs can be used.

GET /Condition?patient=[value]&identifier=[system]|[code]

For example:

GET /Condition?patient=[value]&identifier=http://acme.org/conditiondata|21323-123213

tip

For further information consult the FHIR specification at http://hl7.org/fhir/STU3/search.html#token

Category

To search for Conditions classified by type, the following search constructs can be used.

GET /Condition?patient=[value]&category=[code]
GET /Condition?patient=[value]&category=[system]|[code]
GET /Condition?patient=[value]&category=|[code]
GET /Condition?patient=[value]&category=[system]|

Clinical Status

The search for Conditions by clinical status the following construct can be used.

GET /Condition?patient={id}&clinical-status=active

_lastUpdated

To retrieve Conditions based on the last updated date of the record.

GET /Condition?patient={id}&_lastUpdated={value}

To improve searching the API supports the use of search modifiers. The modifiers supported for date are as below:

Modifier	Description
lt	Returns dates less than the search term
le	Returns dates less than or equal to the search term
gt	Returns dates greater than the search term
ge	Returns dates greater than or equal to the search term
eq	Returns dates equal to the search term

GET /Condition?patient=[value]&_lastUpdated=lt[value]
GET /Condition?patient=[value]&_lastUpdated=le[value]
GET /Condition?patient=[value]&_lastUpdated=gt[value]
GET /Condition?patient=[value]&_lastUpdated=ge[value]
GET /Condition?patient=[value]&_lastUpdated=eq[value]

So to search for a Condition last updated on 23rd January 2021 the query would be:

GET /Condition?patient=[value]&_lastUpdated=2021-01-23

To search for all Conditions last updated before the 23rd December 2020 the query would be:

GET /Condition?patient=[value]&_lastUpdated=lt2020-12-23

_summary

Adding the _summary=count query parameter will change the behaviour of the query to return just the count of records, rather than the records themselves.

GET /Condition?patient={id}&_summary=count

This will return a response like:

{
    "resourceType": "Bundle",
    "type": "searchset",
    "total": 15,
    "id": "df23fd8b-d30c-47c6-a2bd-64c8a24b1166"
}

This can be added to any query construct.

_format

The API supports both XML and JSON formats. The default format is JSON. The format can be requested either using HTTP headers or via the use of the _format query parameter as per the following table.

Format Value	API Response Format
xml	XML
text/xml	XML
application/xml	XML
application/fhir+xml	XML
json	JSON
text/json	JSON
application/json	JSON
application/fhir+json	JSON

GET /Condition?patient={id}&_format=[format value]

For example the query below would return a response in XML format.

GET /Condition?patient={id}&_format=xml

This can be added to any query construct.

Sort Parameters

The default sort order for Condition records is in descending date order (i.e. most current first). The following sort parameters are also available.

Date

The Condition resource can be sorted by onset date or asserted date.

GET /Condition?_sort=onset-date
GET /Condition?_sort=-onset-date
GET /Condition?_sort=asserted-date
GET /Condition?_sort=-asserted-date

Paging

_count

The parameter _count is defined as a hint to the server regarding how many resources should be returned in a single page.

For example the query below would return a Bundle with 5 records per page.

GET /Condition?patient={id}&status={code}&_count=5

Examples

Examples of payloads in both XML and JSON formats are available from the examples section of this site.