Table 1

Characteristics of the worse eye in children with ‘definite DED’ and ‘symptomatic DED’

Characteristics	Non-definite DED	Definite DED	P value	Non-symptomatic DED	Symptomatic DED	P value
Subjects (N, %)	2545 (94.47)	149 (5.53)		2460 (91.3)	234 (8.69)
Mean (±SD) age (year)	7.50±0.50	7.46±0.50	0.335*	7.50±0.50	7.47±0.50	0.353*
Male (%)	1360 (53.44)	91 (61.07)	0.069†	1308 (53.17)	143 (61.11)	0.020†
OSDI	2.40±5.89	24.68±14.57	<0.001*	1.62±2.91	24.83±15.18	<0.001*
TBUT (seconds)	5.58±2.28	3.99±0.72	<0.001*	5.51±2.27	5.35±2.08	0.492*
CFSS	0.65±1.14	1.05±1.36	<0.001*	0.66±1.15	0.73±1.21	0.428*
Outdoor activity (hour/day)	1.79±0.89	1.70±0.91	0.137*	1.79±0.89	1.67±0.85	0.038*
Time of watching TV (hour/day)	0.85±0.72	1.04±0.89	0.016*	0.84±0.72	1.00±0.87	0.011*
Time of using smartphone (hour/day)	0.48±0.60	0.74±0.91	0.001*	0.47±0.60	0.71±0.85	<0.001*
Time of using tablet (hour/day)	0.42±0.56	0.59±0.67	<0.001*	0.41±0.56	0.55±0.63	<0.001*
Time of using computer (hour/day)	0.15±0.38	0.22±0.49	0.268*	0.15±0.38	0.21±0.49	0.241*
Time of doing homework (hour/day)	1.12±0.37	1.22±0.45	0.001*	1.12±0.36	1.27±0.49	<0.001*

*By Wilcoxon rank-sum test,
†By Χ² test.
CFSS, corneal fluorescein staining score; DED, dry eye disease; N, number; OSDI, Ocular Surface Disease Index; TBUT, tear break-up time.