The changes to AMI8a in the April specs seem to make it treat Diagnostic Study, Result: differently than other measures that use Diagnostic Study, Result:

■AND:
■OR: "Occurrence A of Diagnostic Study, Result: Hospital Measures-ECG Impression (result: 'Hospital Measures-LBBB')"
■OR: "Occurrence A of Diagnostic Study, Result: Hospital Measures-ECG Impression (result: 'Hospital Measures-Acute or Evolving MI')"

I would assume that the typical workflow in a hospital is for:
Diagnostic Study, Ordered: ECG
Diagnostic Study, Performed: ECG
Diagnostic Study is interpreted and gives Diagnostic Study, Result: (normal, LBBB, Acute or Evolving MI)

I don't see how this additional layer of ECG Impression fits in? The way it's spec'ed with the April release implys:

Diagnostic Study, Ordered: ECG
Diagnostic Study, Performed: ECG
Diagnostic Study, Result: ECG Impression
Diagnostic Study, Result: Result: (normal, LBBB, etc)

would hospitals truely be sending the data in this manner?

PN6 seems to follow my first outlined workflow when it's examining the Chest XRay or CT Scan, it doesn't include a layer for the interpretation of the Xray or CT Scan:

■OR: "Diagnostic Study, Result: Hospital Measures-Chest xray SM-CT (result: 'Hospital Measures-Radiological findings normal')" during "Occurrence A of Encounter, Performed: Encounter Inpatient (facility location arrival datetime, facility location: 'Hospital Measures-ICU Locations')"

this seems to follow the work flow of:
Diagnostic Study, Ordered: Chest Xray
Diagnostic Study, Performed: Chest Xray
Diagnostic study is interpreted and gives Diagnostic Study, Result: Findings normal

the VTE measures also seem to follow this 'no interpretation layer' model.