FHIR Data Segmentation for Privacy (DS4P) STU2 (PSS-2505)

This project seeks to update the FHIR DS4P to expand existing content to cover known issues, requirements that have emerged since STU1, and provide additional implementation-level guidance. A draft list of anticipated updates is as follows:

- More guidance on the SLS implementation and defining a standard API interface via a FHIR $ operation. 

- revamp sensitivity codes to add new codes and retire the outdated ones.

- update the use case narrative and seek international use cases.

- seek international feedback on the current valuesets.

- news extensions to record additional metadata based on industry feedback (e.g., a timestamp extension to record the date and time of the assignment for each label)

- update the narrative and add an informative summary ("cheat sheet") for implementers.- address high-water mark which was left as future work in STU1.

Regarding US-realm-specific subsections:

- Define code for each of the new categories of sensitive data as recognized by US jurisdictions (e.g., Maryland, California, etc.)

- A US-realm specific table mapping each existing jurisdictional policy that identifies a sensitivity class to the corresponding sensitivity code from terminology.

- references to the clinical value sets (e.g. VSAC) that sets up the baseline of clinical codes for each sensitivity category.