Table 2.

Demographic characteristics in Discovery group. HC and LDH-CP was age- and gender-matched, but significant difference in education level (p < 0.01) and current smoking status (p = 0.02). Two-tailed t-test was performed for parametric data and chi-square test was performed for categorical data.

	HC (n = 68)		LDH-CP (n = 68)		p value
	Mean or n	SEM or %	Mean or n	SEM or %
Age	43.7	1.7	44.0	1.5	0.87
Male	41	60.3	43	63.2	0.72
Low education	24	35.29	44	64.71	< 0.01
Current smoking	9	13.2	20	29.4	0.02