• Initial Patient Population =
  • AND: "Patient Characteristic Birthdate: birth date" >= 18 year(s) starts before start of "Occurrence A of Encounter, Performed: Non-Elective Inpatient Encounter"
  • AND: "Occurrence A of Encounter, Performed: Non-Elective Inpatient Encounter (length of stay <= 120 day(s))"
  • AND: "Occurrence A of Encounter, Performed: Non-Elective Inpatient Encounter (discharge datetime)" during "Measurement Period"
  • AND:
    • OR: "Diagnosis, Active: Ischemic Stroke (ordinality: 'Principal Diagnosis')"
    • OR: "Diagnosis, Active: Hemorrhagic Stroke (ordinality: 'Principal Diagnosis')"
    • starts during "Occurrence A of Encounter, Performed: Non-Elective Inpatient Encounter"

Questions:

1. For the above block of conditions, is “Occurrence A” determined on a condition by condition bases or is “Occurrence A” the same QDM instance for each condition within the Initial Patient Population? (ie. Is the “Occurrence A Encounter, Performed: Non-Elective Inpatient Encounter” that is being evaluated against patient birthdate the same QDM instance that is being evaluated against the length of stay and Measurement Period?)
   • (a) If NO then: Is there ever a situation where a specific occurrence/instance of a QDM would be evaluated against multiple conditions (by design, not by coincidence); excluding the OR conditions that consist of two bullet points?
2. For the first condition above, is “Occurrence A of Encounter, Performed: Non-Elective Inpatient Encounter”…
   • (a) … the Encounter, Performed: Non-Elective Inpatient Encounter with the earliest start date within the QRDA I?
   • (b) … the first Encounter, Performed: Non-Elective Inpatient Encounter to appear in the QRDA I, regardless of start date?
   • (c) … the first of all Encounter, Performed: Non-Elective Inpatient Encounters in the QRDA I that makes the condition evaluate to true (birthdate >= 18yrs start before start of QDM)?
     • (i) If YES then: When evaluating a list of QDMs against a condition to find the “Occurrence A”, should the list of QDMs be ordered by its start date or by the order in which it appears in the QRDA I?
   • (d) … why (and under what circumstances) it is possible to have multiple occurrences of an Inpatient Encounter contained within the same QRDA?