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# HKClinicalCoding

A clinical coding that represents a medical concept using a standardized coding system.

```
class HKClinicalCoding
```

## Overview

A clinical coding pairs a [`system`](/documentation/HealthKit/HKClinicalCoding/system), an optional [`version`](/documentation/HealthKit/HKClinicalCoding/version),
and a [`code`](/documentation/HealthKit/HKClinicalCoding/code) which identify a medical concept.

This model is closely related to the [FHIR Coding model](https://build.fhir.org/datatypes.html#Coding).

## Topics

### Initializers

[`init?(coder: NSCoder)`](/documentation/HealthKit/HKClinicalCoding/init(coder:))

[`init(system: String, version: String?, code: String)`](/documentation/HealthKit/HKClinicalCoding/init(system:version:code:))

Creates a clinical coding with the specified system, version, and code.

### Instance Properties

[`var code: String`](/documentation/HealthKit/HKClinicalCoding/code)

The clinical code that represents a medical concept inside the coding system.

[`var system: String`](/documentation/HealthKit/HKClinicalCoding/system)

The string that identifies the coding system that defines this clinical code.

[`var version: String?`](/documentation/HealthKit/HKClinicalCoding/version)

The version of the coding system.

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`NSCoding`](/documentation/Foundation/NSCoding)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`CVarArg`](/documentation/Swift/CVarArg)

[`NSCopying`](/documentation/Foundation/NSCopying)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Sendable`](/documentation/Swift/Sendable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

[`Hashable`](/documentation/Swift/Hashable)

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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