## deriveIdentifierSearchParameter() function [​](/content/docs/sdk/core.deriveidentifiersearchparameter#deriveidentifiersearchparameter-function "Direct link to deriveIdentifierSearchParameter(/index.html) function")

Derives an "identifier" search parameter from a reference search parameter.

FHIR references can have an "identifier" property.

Any FHIR reference search parameter can be used to search for resources with an identifier.

However, the FHIR specification does not define an "identifier" search parameter for every resource type.

This function derives an "identifier" search parameter from a reference search parameter.

**Signature:**

```typescript
export declare function deriveIdentifierSearchParameter(inputParam: SearchParameter): SearchParameter;
```

## Parameters [​](/content/docs/sdk/core.deriveidentifiersearchparameter#parameters "Direct link to Parameters"/index.html)

| Parameter   | Type             | Description                                           |
| ----------- | ---------------- | ----------------------------------------------------- |
| inputParam  | SearchParameter  | The original reference search parameter.               |

**Returns:**

SearchParameter

- [deriveIdentifierSearchParameter() function](/content/docs/sdk/core.deriveidentifiersearchparameter#deriveidentifiersearchparameter-function/index.html)
- [Parameters](/content/docs/sdk/core.deriveidentifiersearchparameter#parameters/index.html)