To generate an HL7 Version 3 CDA document, the first step is to create a VMD file that accepts incoming HL7 messages, extracts data from them, and converts the extracted data to XML format.

	Dividing the conversion process into two parts - converting the data to XML format, then converting the XML format data to HL7 CDA document format - makes it possible to reuse parts of this process in other solutions. If you need to generate message data in another format, you can reuse the VMD file described in this section to generate data in XML format. You can then write a VMD file to read the XML format data and generate the message data in the other format.

To create this VMD file, perform the following steps:

• Start Chameleon if it is not already started. Close the News Feed window if it appears.
• In the Toolbar, click New to start a new VMD file.
• Click Browse to display the Message Browser window, if it is not already visible.
• In the top panel of the Message Browser window, copy a sample incoming message. For this tutorial, you can use the following message: v3cda_src.txt.
• Click Parse to parse the sample message.
• Click the Segments with red icons are unrecognized link that appears.
• In the Import Unrecognized Segments window, select the Import segments from a library radio button, and select HL7 2.6 from the list box.
• Click Next, Next and Finish. The segments in your test messages are now imported, and are displayed in the Workspace panel at left.
• In the Message Browser window, click the Message is unrecognized link that appears.
• Click Finish. A message definition appears in the Workspace panel. Its Message Identity is set to ADT^A04, which is the message type of the sample message.
• In the Toolbar, click Table. A table definition named Table0 appears in the Workspace panel.
• Right-click Table0, and select Rename. Rename the table Patient.
• Double-click Patient to display its table window.
• Add rows to the table to make it look like this:

• In the Workspace, in the Patient message definition, double-click Message Grammar. The Message Grammar window appears.
• Drag the PID segment from the Workspace to the Segment Grammar panel of the Message Grammar window.
• Drag the Patient table from the Workspace to the Table Grammar panel of the Message Grammar window. The Message Grammar window should look like this:

• In the Message Grammar window, in the Table Grammar panel, double-click Patient. Click OK to close the window that notifies you that you need to select a grammar root.
• In the Grammar Root Selection window that appears, select PID and click OK.
• In the Mapping window that appears, expand 5 - Patient Name, and drag 2 - Given Name to the Mapping column of the PatientFirstName row of the table.
• In 5 - Patient Name, expand 1 - Family Name, and drag 1 - Surname to the PatientLastName row of the table. The Mapping window should now look like this:

• The VMD file to generate XML output is now completed. From the File menu, click Save to save your file.

	To view a copy of this VMD file, follow this link: v3cda_xml.vmd.