The CDA Example repository contains examples reviewed and approved by the Structured Document Work Group.
All examples are automatically validated against C-CDA 3.0 or later using FHIR Structure Definition validation.
Wherever possible, examples have also been validated against C-CDA 2.1's schematron. This can be done manually by executing the following on a local copy of the repository (prereq: NodeJS)
(Only need to run npm i once)
npm i
npm run 2.1
This will validate all input/examples files against the C-CDA 2.1 schematron with Companion Guide 4.1 additions.