Supported search parameter types

The following table shows the supported search parameter types in HealthLake.

Supported search parameters types

Search parameter	Description
_id	Resource id (not a full URL)
_lastUpdated	Date last updated. Server has discretion on the boundary precision.
_tag	Search by a resource tag.
_profile	Search for all resources tagged with a profile.
_security	Search on security labels applied to this resource.
_source	Search on where the resource comes from.
_text	Search on the narrative of the resource.
createdAt	Search on custom extension - createdAt.

Note

The following search parameters are only supported for datastores created after December 09, 2023 : _security, _source, _text, createdAt.

The following table shows examples of how to modify query strings based on specified data types for a given resource type. For clarity, special characters in the examples column have not been encoded. To make a successful query ensure that the query string has been properly encoded.

Search Parameter Types	Details	Examples
Number	Searches for a numerical value in a specified resource. Significant figures are observed. The number of significant digits are specific in by search parameter value, excluding leading zeros. Comparison prefixes are allowed.	[parameter]=100 [parameter]=1e2 [parameter]=lt100
Date/DateTime	Searches for a specific date or time. The expected format is yyyy-mm-ddThh:mm:ss[Z|(+|-)hh:mm] but can vary. Accepts the following data types: date, dateTime, instant, Period, and Timing. For more details using these data types in searches, see date in the FHIR Documentation Index. Comparison prefixes are allowed.	[parameter]=eq2013-01-14 [parameter]=gt2013-01-14T10:00 [parameter]=ne2013-01-14
String	Searches for a sequence of characters in a case-sensitive manner. Supports both HumanName and Address types. For more details, see the HumanName data type entry and the Address data type entries in the FHIR Documentation Index. Advanced search is supported using :text modifiers.	[base]/Patient?given=eve [base]/Patient?given:contains=eve
Token	Searches for a close-to-exact match against a string of characters, often compared to a pair of medical code values. Case sensitivity is linked to the code system used when creating a query.Subsumption-based queries can help reduce issues linked to case sensitivity. For clarity the | has not been encoded.	[parameter]=[system]|[code]: Here [system] refers a coding system, and [code] refers to code value found within that specific system. [parameter]=[code]: Here your input will match either a code or a system. [parameter]=|[code]: Here your input will match a code, and the system property has no identifier.
Composite	Searches for multiple parameters within a single resource type, using the modifiers$ and , operation. Comparison prefixes are allowed.	/Patient?language=FR,NL&language=EN Observation?component-code-value-quantity=http://loinc.org|8480-6$lt60 [base]/Group?characteristic-value=gender$mixed
Quantity	Searches for a number, system, and code as values. A number is required, but system and code are optional. Based on the Quantity data type. For more details, see Quantity in the FHIR Documentation Index. Uses the following assumed syntax [parameter]=[prefix][number]|[system]|[code]	[base]/Observation?value-quantity=5.4|http://unitsofmeasure.org|mg [base]/Observation?value-quantity=5.4|http://unitsofmeasure.org|mg [base]/Observation?value-quantity=5.4|http://unitsofmeasure.org|mg [base]/Observation?value-quantity=le5.4|http://unitsofmeasure.org|mg
Reference	Searches for references to other resources.	[base]/Observation?subject=Patient/23 test
URI	Searches for a string of characters that unambiguously identifies a particular resource.	[base]/ValueSet?url=http://acme.org/fhir/ValueSet/123
Special	Searches based on integrated medical NLP extensions.