Tech Notes: Outcomes

Hospital Discharge Data:

Number of discharges includes all discharges for the specified condition. Because the unit of analysis is the discharge and not the beneficiary, some beneficiaries who are admitted to the hospital for the same condition more than once in a given year will be counted more than once.

Discharge rates per 1000 enrollees were calculated as the number of discharges divided by the total number of beneficiaries enrolled in any Medicare Part A. The denominator for this rate comes from the beneficiary information, including those beneficiaries with any Part A enrollment.

Mean nights of stay were calculated as the sum of all nights of stay divided by the number of discharges. Stays with admission and discharge dates of the same day have a night of stay equal to zero.

Inpatient mortality rates per 100 discharges were calculated as the number of patients who died while in hospital divided by the total number of discharges. Patients with a discharge status code of deceased and a date of death equal to the discharge date were classified as having died while in hospital. Reason for mortality is unknown in these data.

30-day readmission rates per 100 discharges were calculated as the number of patients who were readmitted within 30-days of discharge divided by the midpoint population at risk (number of live discharges minus half of the deaths during the interval). Beneficiaries could be readmitted for any reason.

30-day mortality rates per 100 discharges were calculated as the number of live discharges who died within 30-days of discharge divided by the number of live discharges. Reason for mortality is unknown in these data.