Scenario 1 -
Patient (age > 18) with principle diagnosis of Pneumonia is admitted directly to a NON-ICU location and is transferred to ICU. (no ED Encounter prior to inpatient admission) Patient got a Chest Xray and antimicrobial medications within 24 hours of admission, is not in a clinical trial, is not comfort measures only, has no excluding diagnoses, procedures or interventions.

Scenario 2 -
Patient (age > 18) with principle diagnosis of Pneumonia goes to an ED is admitted to an ICU location and is transferred to Non-ICU.Patient got a Chest Xray and antimicrobial medications within 24 hours of admission, is not in a clinical trial, is not comfort measures only, has no excluding diagnoses, procedures or interventions.

Since the qualification logic for IPP1 and IPP2 are exactly the same, both patients would be in IPP1 and IPP2.

Both patients would qualify for denominator 1 AND denominator 2 under the current definition.

Looking at the denominator 2 inclusion criteria it appears to check for Non-ICU admissions with no ED encounter before the Non-ICU admission AND no ICU location BEFORE the Non-ICU admission:

OR :
AND NOT: "Occurrence A of Encounter, Performed: Hospital Measures-Encounter ED (facility location arrival datetime)" <= 24 hour(s) starts before start of "Occurrence A of Encounter, Performed: Encounter Inpatient (facility location: 'Hospital Measures-Non-ICU Locations')"
AND NOT: "Occurrence A of Encounter, Performed: Encounter Inpatient (facility location arrival datetime, facility location: 'Hospital Measures-ICU Locations')" starts before start of "Occurrence A of Encounter, Performed: Encounter Inpatient (facility location arrival datetime, facility location: 'Hospital Measures-Non-ICU Locations')"

Or it looks for a patient that was admitted to a Non-ICU location after an ED Encounter:

OR:
AND: "Occurrence A of Encounter, Performed: Encounter Inpatient (facility location arrival datetime, facility location: 'Hospital Measures-Non-ICU Locations')" starts after end of "Occurrence A of Encounter, Performed: Hospital Measures - Encounter ED (facility location arrival datetime)"
AND: "Diagnosis, Active: Hospital Measures-Presumptive pneumonia" starts during "Occurrence A of Encounter, Performed: Hospital Measures-Encounter ED"

The patients described in my scenarios would pass one or the other of these logic sections, thus resulting in their appearance in the denominator 2 and also would have passed into the denominator 1.

When the results are aggregated, the patient would be counted twice.