Evaluating hospital readmission rates after discharge from inpatient rehabilitation
OBJECTIVE: To examine facility-level rates of all-cause, unplanned hospital readmissions for 30 days following discharge from inpatient rehabilitation facilities (IRFs).
DESIGN: Using an observational design, we analyzed Medicare claims in order to develop an all-cause, risk-adjusted hospital readmission measure.
SETTING: We used national Medicare inpatient claims and enrollment data for Medicare beneficiaries who were discharged from IRFs in 2013-2014 and met specific inclusion criteria (1,166 IRFs).
PARTICIPANTS: Medicare fee-for-service beneficiaries (n = 567,850 patient-stays).
INTERVENTIONS: Not applicable.
MAIN OUTCOME MEASURE: The outcome is all-cause, unplanned hospital readmission rates for IRFs. We adapted previous risk-adjustment and statistical approaches used for acute care hospitals to develop a hierarchical logistic regression model that estimates a risk-standardized readmission rate for each IRF. The IRF risk-adjustment model takes into account patient demographics, hospital diagnoses and procedure codes, function at IRF admission, comorbidities, and prior hospital utilization. We produced distributions of observed and risk-standardized readmission rates and estimated confidence intervals to make statistical comparisons relative to the national average. We also analyzed the number of days from IRF discharge until hospital readmission.
RESULTS: The national observed hospital readmission rate by 30 days post-IRF discharge was 13.1%. The mean IRF unadjusted readmission rate was 12.4% (SD = 3.5%) and the mean risk-standardized rate was 13.1% (SD = 0.8%). The C-statistic for our risk-adjustment model was 0.70. Nearly three-quarters (73.4%) of IRFs had readmission rates that were significantly different from average. The mean number of days to readmission was 13.0 (SD = 8.6) days and varied by rehabilitation diagnosis.
CONCLUSIONS: Our results demonstrate the ability to assess IRFs' post-discharge hospital readmission rates and the ability to discriminate between IRFs with higher- and lower-than-average hospital readmission rates.