Table 2.
Significant factors predicting length of stay
| Factor | Beta coefficient (h)1 | Std. error | P value |
| Constant | 22.7 | 7.8 | 0.004 |
| Simultaneous bilateral total knee arthroplasty | 46.1 | 4.1 | < 0.001 |
| Gender (female) | 4.3 | 1.7 | 0.012 |
| Age (per 10 yr) | 3.5 | 1.0 | < 0.001 |
| Patient is married | -4.8 | 1.9 | 0.011 |
| Number of allergies | 1.1 | 0.4 | 0.005 |
| Holiday week surgery | -9.4 | 3.6 | 0.011 |
| Surgery end time | 0.8 | 0.4 | 0.040 |
| Black/African American | 6.1 | 3.0 | 0.047 |
1
In our study population, the constant for length of stay (LOS) was 22.7 h. Adding or subtracting beta coefficients for other factors predicts individual patient LOS.