​Thank you for bringing your concern to our attention. Rationale for using the Principal Diagnosis for the Psychiatric visit (encounter) has been because patients seen in psychiatry setting may have more serious (not comparable) primary psychiatric conditions with underlying or secondary depression. It was determined by the measure development workgroup that in this setting only, major depression or dysthymia needed to be the primary diagnosis for the patient. Recent QDM updates have allowed us to directly tie the diagnosis to the encounter using the diagnosis attribute for the encounter. This requires that the listed diagnosis is what the patient was being seen for at this encounter. Prior logic only required the encounter happen while the diagnosis was active, but it did not require that that was the actual reason for the visit. Work is under way to introduce additional exclusions that will negate the need to use the " Principal Diagnosis" attribute. However, we will likely need to use the "Diagnosis" attribute for the Pyschiatric visit (encounter) for the reasons stated above.

CQM159v5 measure logic requires specification of "principal" diagnosis for psych visit, although CMS does not require a principal diagnosis for billing in outpatient setting. It is typically hospital billing requirement. This causes additional burden on the provider and IT systems to record this relationship.