Parameter
|
Estimate
|
Wald 95% Confidence Limits
|
Wald Chi-Square
|
P-Value
|
---|
Intervention period (ref Before)a
|
−0.085
|
−0.169
|
−0.001
|
3.97
|
0.046
|
Day of surgery (ref Monday)
|
Tuesday
|
0.075
|
−0.071
|
0.221
|
1.02
|
0.313
|
Wednesday
|
0.120
|
− 0.035
|
0.275
|
2.31
|
0.128
|
Thursday
|
0.174
|
0.004
|
0.346
|
4.00
|
0.046
|
Friday
|
0.033
|
−0.114
|
0.180
|
0.19
|
0.662
|
Male
|
0.155
|
0.063
|
0.248
|
10.86
|
0.001
|
Total knee arthroplasty
|
0.009
|
−0.137
|
0.155
|
0.01
|
0.905
|
Unilateral procedure
|
0.251
|
0.037
|
0.464
|
5.30
|
0.021
|
Osteoarthritis
|
0.118
|
−0.113
|
0.349
|
1.00
|
0.317
|
Surgery start, morning
|
0.039
|
−0.058
|
0.136
|
0.61
|
0.433
|
ASA 3 or 4
|
−0.041
|
−0.134
|
0.052
|
0.76
|
0.384
|
English-speaking interpreter required
|
−0.146
|
−0.237
|
− 0.055
|
9.88
|
0.002
|
Other lower limb or back issues
|
−0.057
|
−0.144
|
0.029
|
1.71
|
0.191
|
ICU/HDU admission
|
−0.352
|
−0.524
|
− 0.180
|
16.06
|
<.0001
|
Acute complication
|
−0.389
|
−0.485
|
− 0.294
|
63.91
|
<.0001
|
Peripheral nerve block
|
−0.033
|
−0.163
|
0.097
|
0.25
|
0.616
|
Age, yrs
|
0.012
|
0.007
|
0.018
|
22.27
|
<.0001
|
Body mass index, kg/m2
|
0.007
|
0.001
|
0.014
|
4.43
|
0.035
|
- The incident risk ratio derived from the estimate is 0.92 (0.85 to 1.00). Thus the intervention period was associated with an 8.1% reduction in length of stay
- Legend: ASA American Society of Anesthesiologists, ICU Intensive Care Unit, HDU High Dependency Unit, yrs years
- arefer to Before period