I finished my Trifolia template comparison tool last night and used it to compare C-CDA 1.1 to C-CDA 2.1. You can find my detailed report here. A quick summary of results follows along with some general observations:
|Major||21||Most were issues where 1.1 is more restrictive (has SHALL constraints) in content that MAY be present. It's the "X, if present, SHALL" that causes a potential problem. These constraints most often appear in performer//addr and performer//telecom. There are also a couple of possibly missed constraints, though CCDA 1.1 doesn't always follow the same patterns with Narrative text constraints.|
|Minor||3||These were mostly cases where a deprecated template which was removed in C-CDA 2.1 might need to be addressed in a SHOULD NOT constraint, just to make the point. If folks strongly disagree, I can back down.|
|Future||9||Minor inconsistencies in constraint splitting, or where something might be fixed or clarified without changing the meaning. These can all wait for later as maintenance as far as I'm concerned.|
|Total||33||Overall, not bad for several dozen pages of constraints.|
You can get the comparison stylesheet here. Tonight I'm probably going to compare 2.0 to 2.1 just to see what shows up. That has a different purpose. I want to see what it takes to create a 2.1/2.0 aware C-CDA consumer. I think that might be a useful document to add to the C-CDA 2.1 package.