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# documentData

The CDA document stored as XML data.

```
var documentData: Data? { get }
```

## Discussion

The CDA document’s XML format is specified by the [Clinical Document Architecture, R2](http://www.hl7.org/implement/standards/product_brief.cfm?product_id=7) standard. .

When using an [`HKDocumentQuery`](/documentation/HealthKit/HKDocumentQuery) object to retrieve documents from the HealthKit store, if the query’s [`includeDocumentData`](/documentation/HealthKit/HKDocumentQuery/includeDocumentData) property is set to <doc://com.apple.documentation/documentation/Swift/false>, the retrieved documents will have `nil`-valued `documentData` properties.

---

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