The process for creating the Reference Data is described in Reference Data development.

Once the Reference Data for the DEX is created, the ontologies that are used by the DEX should be listed in the <dex.reference_data> element within the dex.xml file.

The penultimate stage in developing the DEX is to create an XML Schema that is specific to the DEX. This should be a complete subset of the PLCS PSM Schema.

The final stage in developing the DEX is to create XML test data that is specific to the DEX. This should provide an example of the use of the DEX and provide data that can be used to test any DEX implementation.