Table 1.

The detailed data about levels of pre- and postoperative pain based on numerical rating scale.

	Pain (Numerical Rating Scale score)
	Pre-operation	Post-operation	P value
Surgery
Laminectomy & discectomy	7.66 ± 2.27	3.72 ± 2.82	< .001
Laminotomy & discectomy	7.18 ± 2.13	4 ± 3.07	< .001
Gender
Male	7.66 ± 2.28	4.4 ± 3.45	.006
Female	7.24 ± 2.14	3.56 ± 2.58	< .001
Age
< 50 yrs/old	7.21 ± 2.11	3.64 ± 3.12	.001
> 50 yrs/old	7.5 ± 2.24	4 ± 2.87	< .001
Cigarette smoker
Yes	7.16 ± 2.63	6.5 ± 3.98	.63
No	7.44 ± 2.13	3.41 ± 2.49	< .001
Opium addict
Yes	7.25 ± 2.36	5.25 ± 4.42	.51
No	7.41 ± 2.19	3.72 ± 2.76	< .001

Data are shown as mean ± standard deviation.