Visual Sequelae of Computer Vision Syndrome: A Cross-Sectional Case-Control Study

Table 10

Data summary of the mfERG subgroup.

Parameters	mfERG students from control group; (n = 20 eyes of 20 students); (Mean ± SD); Median (range)	mfERG of students from CVS group; (n = 20 eyes of 20 students); (Mean ± SD); Median (range)	Mean difference (mini−control−risk) 95% confidence of interval	value
Age	22.35 ± 1.53	21.95 ± 2.14	0.4	0.50
	22 (19 : 25)	21 (19 : 25)	(−0.79 : 1.59)
Gender:
Male	8 (40%)	8 (40%)		1.00
Female	12 (60%)	12 (60%)
Screen-hours:
1 h	4 (20%)	0
2 h	3 (15%)	1 (5%)		0.09
3 h	3 (15%)	1 (5%)
4 h	2 (10%)	4 (20%)
5 h	5 (25%)	5 (25%)
≥6 h	3 (15%)	9 (45%)
- mfERG students < 3 screen-hours	10 (50%)	2 (10%)		0.006
- mfERG students ≥3 screen-hours	10 (50%)	18 (90%)
Screen-time:
Day	12 (60%)	5 (25%)		0.03
Night	8 (40%)	15 (75%)
Screen-illumination:
10%	5 (25%)	1 (5%)		0.06
30%	7 (35%)	3 (15%)
50%	5 (25%)	5 (25%)
80%	2 (10%)	6 (30%)
100%	1 (5%)	5 (25%)
- mfERG students ≤50% illumination	17 (85%)	9 (45%)		0.01
- mfERG students >50% illumination	3 (15%)	11 (55%)
Commonest screen used:
Desktop computers	0	2 (10%)		0.4
Laptops	1 (5%)	2 (10%)
Apple	4 (20%)	4 (20%)
Android	14 (70%)	12 (60%)
Other screens	1 (5%)	0
mfERG findings:
I-amplitudes P1 (nV/deg2):
Ring 1 (normal 66.6–130.8)	80.60 ± 19.71	54.01 ± 9.17	26.59 (16.75 : 36.43)	<0.0001
	76.49 (45.26 : 141.4)	52.86 (40.43 : 74.09)
Ring 2 (normal 30.9–77.8)	35.75 ± 6.94	30.55 ± 5.97	5.20 (1.05 : 9.34)	0.02
	34.76 (25.08 : 52.74)	30.97 (15.17 : 40.61)
Ring 3 (normal 21.7–59)	19.80 ± 3.80	18.57 ± 3.67	1.22 (−1.17 : 3.62)	0.31
	20.08 (13.38 : 25.3)	18.27 (11.54 : 25.36)
Ring 4 (normal 12.9–37.1)	12.62 ± 2.52	10.50 ± 2.40	2.11 (0.54 : 3.69)	0.01
	12.87 (8.87 : 17.38)	10.21 (4.98 : 14.37)
Ring 5 (normal 10–28.2)	9.69 ± 2.55	7.82 ± 1.81	1.88 (0.46 : 3.29)	0.01
	9.13 (5.51 : 14.51)	7.74 (4.57 : 10.93)
II-amplitudes P1 (nV/deg2):
Quadrant 1 (normal 15.8–42.74)	11.26 ± 3.76	9.17 ± 2.01	2.09 (0.16 : 4.03)	0.03
	10.83 (5.05 : 19.41)	9.29 (5.12 : 12.48)
Quadrant 2 (normal 15.98–42.75)	14.39 ± 2.81	12.03 ± 2.98	2.36 (0.51 : 4.22)	0.01
	13.91 (9.58 : 18.71)	12.09 (5.63 : 17.54)
Quadrant 3 (normal 15.18–42.05)	15.13 ± 3.06	12.80 ± 3.46	2.33 (0.24 : 4.42)	0.03
	13.69 (10.6 : 21.02)	12.60 (5.23 : 18.4)
Quadrant 4 (normal 13.87–39.61)	10.27 ± 2.41	9.20 ± 2.18	1.07 (−0.40 : 2.54)	0.15
	9.98 (6.62 : 16.02)	8.49 (6.09 : 16.02)
III-foveal functions:
Normal foveal response (21 eyes)	20 eyes (100%)	3 eyes (15%)		<0.0001
Reduced foveal response (19 eyes)	0 (0%)	17 eyes (85%)