In light of recent smoking concept discussion (SNOMED vs. LOINC): For countries that are members of IHTSDO (USA, UK), it is easier to adopt SNOMED. No need to pay for license (there is national license).
For current non-members, SNOMED license requirement may be an obstacle. (e.g., France, Germany, Italy, China, Japan, Brazil, Mexico).
I understand there is no magic solution here, but I wanted to bring up this difficult subject for at least some discussion. There are some existing CDM datasets from non-member SNOMED countries.
list of SNOMED members: (IHTSDO plans to change its name in 2016, I think)