Exposure factors	Non exposed group		Exposed group		Odds ratio	P value
Exposure factors	Total subject	Dry eyes	Total subject	Dry eyes	Odds ratio	P value
Excessive wind	420	189	25	13	1.3241	0.539
Sunlight/high temp	316	126	129	76	2.1623	0.0003^***
Air pollution	417	191	28	11	0.7656	0.5602
Smoking	383	166	62	36	1.81	0.03^*
Drugs	414	178	31	24	4.55	0.0002^***