Table 1.

Comparison of general data between the two groups

Groups	n	Male/female	Age (year)	Causes of disease				Sites
				steroid-induced	Trauma-induced	alcohol-induced	Others	Unilateral	Bilateral
Observation group	43	25/18	49.35±6.35	14	16	9	4	30	13
Control group	43	23/20	48.63±6.87	13	17	8	5	29	14
X2/t		0.189	0.505	0.186				0.054
P		0.664	0.615	0.829				0.816