Thank you for your inquiry regarding CMS996: Appropriate Treatment for ST-Segment Elevation Myocardial Infarction (STEMI) Patients in the Emergency Department (ED). The measure denominator captures ED encounters for patients 18 years and older with a STEMI diagnosis. As described in the inquiry, the measure has several exclusion criteria, including the exclusion of ED encounters with bleeding or bleeding diathesis (excluding menses), known malignant intracranial neoplasm, known structural cerebral vascular lesion, advanced dementia, pregnancy, and diagnosis of allergy to thrombolytics if these diagnoses start before the start of the ED encounter and do not end before the ED encounter. The measure’s ‘Active Exclusion Diagnosis at the Start of the ED Encounter’ definition found in the human readable file ( https://ecqi.healthit.gov/sites/default/files/ecqm/measures/CMS996v5.html ) shows that the diagnosis prevalencePeriod (or time from diagnosis onset to abatement) “overlaps before” the ED encounter relevantPeriod (or the time the encounter began to the time the encounter ended). Meaning, that diagnoses captured by this exclusion can start before or during the ED encounter for the encounter to be excluded from the measure denominator. Although the presentOnAdmission Indicator attribute is not used for this exclusion, the “overlaps before” measure logic should exclude conditions that were present on admission as long as the “Encounter, Performed”: “Emergency Department Evaluation and Management Visit” relevantPeriod is accurately coded.   The measure developer team may consider using a presentOnAdmission Indicator attribute for the “Encounter, Performed” datatype in a future Annual Update.

Please consider adding logic to the following path to allow diagnosis to also start during the encounter: "Active Exclusion Diagnosis at Start of ED Encounter". Currently the logic is looking at diagnosis that start prior to the encounter and do not end during. This does not account for coded diagnosis with POA = Y as their associated start date/time would be during the encounter.