V. Return Key Attributes

The values of Return Key Attributes to be retrieved with the Query are specified with zero-length (universal matching) in the C-FIND request. SCPs shall support Return Key Attributes defined by a Substance Administration Query Information Model according to the Data Element Type (1, 1C, 2, 2C, 3) as defined in PS 3.5.

Every Matching Key Attribute shall also be considered as a Return Key Attribute. Therefore the C-FIND response shall contain, in addition to the values of the requested Return Key Attributes, the values of the requested Matching Key Attributes.

Notes: 1 The Conformance Statement of the SCP lists the Return Key Attributes of Type 3 that are supported.

2. An SCU may choose to supply any subset of Return Key Attributes.

3. An SCU can not expect to receive any Type 3 Return Key Attributes.

4. Return Key attributes with VR of SQ may be specified either with zero-length, or with a zero-length item in the sequence.