Table 6. Dominant bacteria in Qiang minority and Han.

Groups	Total positive eyes	Corynebacterium		Staphylococcus epidermidis		Intracellular bacteria Sphingomonas
		Positive eyes	Positive rate	Positive eyes	Positive rate	Positive eyes	Positive rate
Qiang	73	20	27.4	24	32.9	13	17.8
Han	87	60	54.1	29	26.1	0	0
Χ2		11.6721		0.6771		18.6442
P		0.001		0.411		0.000

The above results indicated that there were significant differences in dominant bacteria of Corynebacterium and Intracellular bacteria Sphingomonas between two populations. The positive rate of Corynebacterium in Qiang minority was significant higher than that in Han, Intracellular bacteria Sphingomonas is one of dominant bacteria in Qiang minority with dry eye while in Han it does not exist. There was no significant difference in Staphylococcus epidermidis between both populations.