MDS data generally consists structured responses to specific questions about a resident's state. It seems best to record MDS data as observations but we have three questions --

a) Would it be best to treat MDS concepts as a new standard terminology and therefore an extension to the current CDM? There appears to be no usable mapping between MDS and SNOMED CT and MDS is widely used and so might be a good addition to the CDM.

b) There are several different types of MDS reports and it would be important during analyses to know which type of report an observation was entered in. Also, MDS data is recorded at various phases of a resident's care (e.g., enrollment, quarterly, and after interruptions in care). An analyst might need to be selective about the MDS report type or the phase of care from which an observation was recorded. What are the best practices for managing this sort of metadata?

c) Structured responses to specific questions about a resident's state in the MDS tend to be repeated. There is also the option of using numerical values for responses. Should we use numerical responses or free text? Is there a consensus on a best practice?

Thank you very much for your time,