Table 4.

Instrumented posterior fusion with interbody relative to instrumented posterior fusion.

	Relative Risk	98.75% Confidence Interval	P Value*
Any adverse event	0.950	(0.729–1.240)	.633
Minor adverse event	0.955	(0.731–1.247)	.663
Serious adverse event	1.598	(0.416–6.132)	.384
Readmission	1.053	(0.588–1.886)	.825
Operative time** (with interbody [202 min] vs without interbody [183 min]) (mean difference of 19 min)			<.001
Length of stay** (with interbody [3.4 d] vs without interbody [3.4 d]) (mean difference of 0 d)			.554

Bold indicates statistically significant.

^*Controlled for Charlson Comorbidity Index (includes age).

^**T-tests were used to compare these variables (significant at P < .05).