Table 3.
Multilevel Logistic Regression Model Examining Patient and Facility Characteristics Associated with 30-Day Readmission to Acute Care Hospitals
| Odds Ratio | Standard Error | P Value | 95% Confidence Interval | |
|---|---|---|---|---|
| Patient characteristics | ||||
| Age | 0.99849 | 0.00027 | <.001 | 0.99796–0.99902 |
| Female | 0.87515 | 0.00640 | <.001 | 0.86270–0.88778 |
| Race/ethnicity* | ||||
| African American | 1.02137 | 0.01143 | .059 | 0.99922–1.04402 |
| Latino/Hispanic | 0.97522 | 0.01622 | .131 | 0.94395–1.00753 |
| Asian | 0.93097 | 0.02592 | .010 | 0.88153–0.98319 |
| Other | 0.98559 | 0.03369 | .671 | 0.92173–1.05388 |
| Elixhauser comorbidity index | 1.02454 | 0.00051 | <.001 | 1.02354–1.02554 |
| Married | 1.05348 | 0.00764 | <.001 | 1.03863–1.06856 |
| Dysphagia | 0.86300 | 0.00864 | <.001 | 0.84624–0.88009 |
| Pneumonia | 1.15869 | 0.01317 | <.001 | 1.13316–1.18480 |
| Days since impairment onset, ≤10 d | 1 (omitted due to collinearity) | |||
| Days since impairment onset, 10–190 d | 1.01779 | 0.00047 | <.001 | 1.01687–1.01872 |
| Days since impairment onset, 10–190 d, squared | 0.99987 | 4.12e–06 | <.001 | 0.99987–0.99988 |
| Days since impairment onset, ≥190 d | 1.00637 | 0.00093 | <.001 | 1.00455–1.00820 |
| Admission motor FIM | 0.95560 | 0.00037 | <.001 | 0.95487–0.95632 |
| Admission motor FIM, squared | 0.99986 | 0.00002 | <.001 | 0.99982–0.99991 |
| Admission cognitive FIM | 0.99619 | 0.00071 | <.001 | 0.99479–0.99759 |
| Admission cognitive FIM, squared | 1.00077 | 0.00006 | <.001 | 1.00065–1.00089 |
| Admitted Friday–Sunday | 1.03570 | 0.00776 | <.001 | 1.02060–1.05102 |
| Impairment group* | ||||
| Brain dysfunction | 1.37499 | 0.02753 | <.001 | 1.32208–1.43002 |
| Neurologic conditions | 1.37909 | 0.02889 | <.001 | 1.32362–1.43689 |
| Spinal cord dysfunction | 1.23158 | 0.02881 | <.001 | 1.17639–1.28937 |
| Amputation | 1.75687 | 0.04580 | <.001 | 1.66936–1.84898 |
| Arthritis | 1.12919 | 0.07256 | .059 | 0.99556–1.28076 |
| Pain syndromes | 1.23522 | 0.08796 | .003 | 1.07430–1.42023 |
| Orthopedic conditions | 0.87141 | 0.01776 | <.001 | 0.83730–0.90692 |
| Cardiac disorders | 2.04617 | 0.04859 | <.001 | 1.95312–2.14366 |
| Pulmonary disorders | 2.09954 | 0.06810 | <.001 | 1.97022–2.23735 |
| Burns | 1.12702 | 0.11266 | .232 | 0.92649–1.37095 |
| Congenital deformities | 0.72475 | 0.18602 | .210 | 0.43825–1.19857 |
| Other disabling impairments | 1.72285 | 0.07060 | <.001 | 1.58988–1.86693 |
| Major multiple trauma | 0.95384 | 0.02907 | .121 | 0.89854–1.01254 |
| Debility | 1.70522 | 0.03621 | <.001 | 1.63571–1.77769 |
| Medically complex conditions | 1.99545 | 0.09067 | <.001 | 1.82542–2.18131 |
| Facility characteristics | ||||
| Freestanding hospital | 1.14593 | 0.01528 | <.001 | 1.11637–1.17628 |
| Mean admission motor FIM | 0.98078 | 0.00163 | <.001 | 0.97759–0.98399 |
| Mean admission cognitive FIM | 1.00619 | 0.00273 | .023 | 1.00084–1.01156 |
| Mean days since impairment | 1.00199 | 0.00125 | .111 | 0.99954–1.00444 |
All variables were treated as linear predictors except admission motor FIM, admission cognitive FIM, which were treated as quadratic variables, and days since impairment onset, which was treated as a piece-wise variable with linear and quadratic components, based on fit.
Harrell C statistic for final model: 0.71.
*
For race, Caucasian was set as the reference group (odds ratio = 1). For impairment group, stroke was set as the reference group (odds ratio = 1).