Table 2.

Demographic features of enrolled subjects

feature		patients
sex	male	55
	female	1
age(yrs)		37.84 ±11.67
		range 16-63
occupation	factory worker	35
	construction worker	11
	peasant	5
	student	3
	other	2
education	illiteracy	2
	primary school	13
	middle school	36
	university	4
	post-graduate	1
location where injury occurred	workplace	45
	laboratory	4
	home	5
	elsewhere	2