The Effects of Chewing Gum in Preventing Eyestrain
Table 3
Data of between chewing gum and tablet candy in each age group.
Outcomes
20 s ()
30 s ()
40 s ()
50 s ()
value
Median (IQR)
Gum (Δ)
VAS (mm)
Eye tiredness
7.0 (-4.5, 21.3)
2.5 (-5.5, 46.3)
0 (-5.3, 11.8)
1.5 (-15.3, 23.8)
0.794
Eye heaviness
5.0 (-9.3, 19.5)
9.5 (-4.0, 25.8)
-0.5 (-24.8, 13.0)
8.0 (-8.3, 27.3)
0.424
Blurred vision
0 (-0.8, 6.3)
5.5 (0, 21.3)
0 (-15.8, 20.5)
-2.0 (-11.5, 11.8)
0.537
Double vision
0 (-1.8, 5.8)
0.5 (-0.3, 16.3)
0 (0, 8.8)
0.5 (-4.0, 13.3)
0.789
Eye dryness
3.0 (-11.3, 12.8)
17.5 (-0.3, 36.3)
-1.5 (-15.3, 10.3)
-0.5 (-17.3, 6.8)
0.240
Subjective accommodation (D)
-0.2 (-0.9, 0.4)
-0.2 (-0.6, 0.2)
0.2 (-0.1, 0.6)
-0.1 (-0.2, 0.3)
0.055
Spherical equivalent refraction (D)
0 (-0.1, 0.2)
0 (-0.3, 0)
-0.1 (-0.4, 0.3)
0 (-0.3, 0.1)
0.345
Ring break-up time (sec)
-0.1 (-3.2, 0)
0 (-4.2, 0)
-0.2 (-2.8, 2.2)
0 (-1.3, 0.6)
0.417
Tablet candy (Δ)
VAS (mm)
Eye tiredness
14.5 (9.0, 34.3)
14.0 (-17.5, 27.5)
0.5 (-14.0, 24.3)
15.5 (-14.5, 34.8)
0.524
Eye heaviness
3.0 (-0.8, 35.0)
4.0 (-7.8, 20.8)
-1.0 (-17.3, 10.0)
14.0 (-1.8, 28.5)
0.355
Blurred vision
2.0 (-1.5, 18.3)
2.0 (-20.3, 31.0)
2.5 (-10.3, 17.8)
-1.5 (-9.5, 18.5)
0.792
Double vision
0.5 (-3.3, 9.0)
0 (-1.8, 20.5)
4.0 (0, 19.5)
5.5 (-2.0, 12.0)
0.514
Eye dryness
11.0 (-0.8, 32.5)
5.5 (-8.3, 37.0)
0 (-15.8, 10.0)
0 (-25.5, 17.5)
0.237
Subjective accommodation (D)
-0.7 (-1.4, -0.2)
-0.2 (-0.9, 0.3)
0.1 (-0.1, 0.4)†
0 (-0.2, 0.2)‡
< 0.001
Spherical equivalent refraction (D)
0 (-0.3, 0.1)
0 (0, 0.1)
-0.3 (-0.4, 0)§
0 (-0.3, 0.1)
0.010
Ring break-up time (sec)
0 (-1.7, 0)
0 (-5.9, 0)
0 (-0.9, 0)
0 (-0.1, 1.4)
0.221
IQR: interquartile range (25th, 75th percentiles); VAS: visual analog scale. ,; Kruskal-Wallis test. †, (20 s vs. 40 s), ‡, (20 s vs. 50 s), §, (30 s vs. 40 s); Mann–Whitney test with Bonferroni’s correction. : effect size.
