Table 6.

Multivariable adjusted odds ratios for outcome measures.

Outcome	Timing of Outcome
	Discharge	One Year
	Catheter Use	Normal Bladder Function	ODI Score
Participants in model	n = 565	n = 169	n = 200
Explanatory variables
Age	1.00 (0.98–1.02)	1.0 (0.98–1.03)	0.15 (−0.05 to 0.35)
Female	0.98 (0.56–1.72)	0.33 (0.17-0.65)∗	10.92 (5.29-16.54)∗∗
CSF not visible on axial MRI	0.75 (0.43–1.31)	1.00 (0.52–1.94)	−1.25 (−6.68 to 4.18)
Catheter inserted pre-operatively	10.56 (5.81-20.41)∗∗	0.50 (0.24–1.02)∗	3.15 (−2.76 to 9.06)
Days from symptom onset to operation	0.99 (0.96–1.01)	1.01 (0.98–1.04)	0.09 (−0.12 to 0.30)
Admission ODI Score	..	0.98 (0.97-1.00)∗	0.28 (0.17-0.40)∗∗

Multivariable logistic regression for the outcomes of catheter use at discharge and normal bladder function at one year was performed. Adjusted odds ratios with 95% confidence intervals for predictors are shown. Admission ODI and catheter tug findings were not included in the model for discharge catheter use due to the small numbers of participants with complete data. Similar numbers of participants had complete data for ODI at admission and normal bladder function at one year, so ODI at admission was included in the model for normal bladder function. Linear regression was used for the ODI index score at one year. Regression coefficients with 95% confidence intervals are shown for explanatory variables. The measure of time to operation chosen was symptom onset to operation in days as this was the most complete. Those undergoing a planned operation were excluded from the model. (ODI: Oswestry Disability Index, CSF: cerebrospinal fluid, ∗p < 0.05, ∗∗p = <0.001).