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The current archetype tools in use are less clear with respect to single-valued attribute alternatives. The Ocean Archetype Editor (AE) supports the capability via a 'choice' node, but because it does not work the same way under multiple-valued attributes, it can be confusing for users.
In LinkEHR archetype editor 'choice' nodes are automatically created when an alternative over a single attribute is created, and removed if the alternative is removed.
Choice in Container Attributes
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