Table 5.

Univariate Logistic Regression of Overall Infection.

Variate	Odds ratio	Confidence level	p-value
Age	0.982	0.917-1.051	0.593
ASA score = 3 or higher	0.568	0.062-5.175	0.616
Gender	0.506	0.056-4.605	0.545
DM	1.785	0.292-10.924	0.530
BMI	1.152	1.024-1.296	0.019*
Fusion levels	0.809	0.176-3.711	0.785
Operation time	1.844	0.974-3.491	0.601
Drainage tube	2.348	0.252-21.902	0.454

Abbreviation: ASA = American society of anesthesiologists physical status classification system, BMI = body mass index, DM = diabetes mellitus.

*Significant results (p-value < 0.05).