Table 3. Multivariable Random Slope Mixed-Effects Model of Changes in Hospital Length of Stay, 30-day Hospital Readmission, In-Hospital Mortality, and Facility Discharge for Intervention and Control Hospitals Between February 2017 and January 2019.
| Outcome and study phasea | Coefficient (95% CI)b | Slope (95% CI)c | P value | ||
|---|---|---|---|---|---|
| Slope differs from zero | Change in slope from prior slope | Difference in slopes (control vs intervention hospitals) | |||
| Hospital length of stayd | |||||
| Control hospitals, reference group | |||||
| Preintervention phase, Feb 2017 to Jan 2018 | −0.344 (−0.599 to −0.090) | −0.344 (−0.599 to −0.090) | .01 | .03 | NA |
| Intervention phase, Feb 2018 to Jan 2019 | 0.334 (0.026 to 0.642) | −0.011 (−0.281 to 0.260) | .94 | NA | |
| Intervention hospitals | |||||
| Change in level in Feb 2017 | 1.086 (−26.399 to 28.571) | NA | NA | NA | NA |
| Intervention hospital by time interaction during preintervention phase, Feb 2017 to Jan 2018 | 0.378 (−0.332 to 1.089) | 0.034 (−0.646 to 0.714) | .92 | .04 | .09 |
| Intervention hospital by time interaction during intervention phase, Feb 2018 to Jan 2019 | −1.247 (−2.160 to −0.334) | −0.879 (−1.607 to −0.150) | .02 | .03 | |
| 30-d hospital readmission | |||||
| Control hospitals, reference group | |||||
| Preintervention phase, Feb 2017 to Jan 2018 | 0.042 (0.011 to 0.074) | 0.042 (0.011 to 0.074) | .01 | .88 | NA |
| Intervention phase, Feb 2018 to Jan 2019 | −0.005 (−0.063 to 0.054) | 0.038 (−0.023 to 0.099) | .22 | NA | |
| Intervention hospitals | |||||
| Change in level in Feb 2017 | −0.277 (−2.264 to 1.710) | NA | NA | NA | NA |
| Intervention hospital by time interaction during pre-intervention phase, Feb 2017 to Jan 2018 | −0.041 (−0.141 to 0.058) | 0.001 (−0.094 to 0.096) | .99 | .54 | .15 |
| Intervention hospital by time interaction during intervention phase, Feb 2018 to Jan 2019 | 0.061 (−0.129 to 0.251) | 0.058 (−0.136 to 0.251) | .56 | .85 | |
| In-hospital mortality | |||||
| Control hospitals, reference group | |||||
| Preintervention phase, Feb 2017 to Jan 2018 | 0.002 (−0.018 to 0.021) | 0.002 (−0.018 to 0.021) | .88 | .67 | NA |
| Intervention phase, Feb 2018 to Jan 2019 | 0.007 (−0.025 to 0.039) | 0.008 (−0.023 to 0.040) | .60 | NA | |
| Intervention hospitals | |||||
| Change in level in Feb 2017 | −0.340 (−2.121 to 1.442) | NA | NA | NA | NA |
| Intervention hospital by time interaction during pre-intervention phase, Feb 2017 to Jan 2018 | 0.001 (−0.055 to 0.058) | 0.003 (−0.051 to 0.057) | .92 | .39 | >.99 |
| Intervention hospital by time interaction during intervention phase, Feb 2018 to Jan 2019 | 0.036 (−0.066 to 0.137) | 0.045 (−0.052 to 0.143) | .36 | .48 | |
| Facility discharge | |||||
| Control hospitals, reference group | |||||
| Preintervention phase, Feb 2017 to Jan 2018 | 0.024 (−0.023 to 0.072) | 0.024 (−0.023 to 0.072) | .32 | .24 | NA |
| Intervention phase, Feb 2018 to Jan 2019 | −0.041 (−0.110 to 0.028) | −0.017 (−0.088 to 0.055) | .65 | NA | |
| Intervention hospitals | |||||
| Change in level in February 2017 | 3.410 (−1.184 to 8.004) | NA | NA | NA | NA |
| Intervention hospital by time interaction during pre-intervention phase, Feb 2017 to Jan 2018 | −0.001 (−0.148 to 0.146) | 0.023 (−0.117 to 0.163) | .74 | .58 | .77 |
| Intervention hospital by time interaction during intervention phase, Feb 2018 to Jan 2019 | −0.017 (−0.233 to 0.200) | −0.034 (−0.257 to 0.188) | .76 | .88 | |
Abbreviation: NA, not applicable.
a
Time is treated continuously; coefficients and slopes are reported in monthly estimates (eg, change per month).
b
Model includes patient’s age, sex, housing condition, level of health care insurance coverage, Elixhauser comorbidity index, and Hospital Frailty Risk Score.
c
Slope during intervention phase can be derived by summing coefficient from preintervention phase and intervention phase.
d
Regression coefficients and slopes for hospital length of stay are provided in hours.