Table 3. Habits of the students with and without DED symptoms.

		Dry eye (OSDI≥13)
		No		Yes
		N	%	N	%	P-value
Total number of hours spent studying per day	0-3h	28	17.8%	26	10.8%	0.137
	3-6h	75	47.8%	123	51.2%
	>6h	54	34.4%	91	37.9%
Number of hours per day spent studying books and hard copy literature	Not using	2	1.3%	2	0.8%	0.195
	0-3h	34	21.7%	36	15.0%
	3-6h	70	44.6%	131	54.6%
	>6h	51	32.5%	71	29.6%
Number of hours per day spent studying using computers, laptops, and other VD devices	Not using	69	43.9%	73	30.4%	0.007
	0-3h	85	54.1%	148	61.7%
	3-6h	2	1.3%	15	6.3%
	>6h	1	0.6%	4	1.7%
Number of hours per day spent using mobile phones, computers, laptops, and other VD devices in their free time	Not using	0	0.0%	0	0.0%	0.911
	0-3h	75	47.8%	111	46.3%
	3-6h	57	36.3%	87	36.3%
	>6h	25	15.9%	42	17.5%

A Chi square test was performed, p<0.05 was considered as statistically significant.