Table 9.
Differences between the control and CVS groups.
| Parameters | Control group (n = 176 eyes of 176 students) (Mean ± SD) Median (range) |
CVS group (n = 557 eyes of 557 students) (Mean ± SD) Median (range) |
Mean difference (Control-CVS) 95% confidence of Interval |
P value |
|---|---|---|---|---|
| Visual outcomes (logMAR): | ||||
| UDVA | 0.13 ± 0.12 | 0.31 ± 0.25 | −0.18 | <0.0001 |
| 0.1 (−0.1 : 0.5) | 0.3 (−0.1 : 1.1) | (−0.22 : −0.09) | ||
| CDVA | −0.016 ± 0.04 | −0.002 ± 0.01 | −0.014 | <0.0001 |
| 0 (−0.1 : 0) | 0 (−0.1 : 0) | (−0.018 : −0.008) | ||
| Subjective refraction (D): | ||||
| Sphere | −0.51 ± 1.13 | −0.90 ± 1.12 | 0.39 | <0.0001 |
| −0.13 (−4:2.5) | −0.75 (−5:4) | (−0.02 : 0.53) | ||
| Cylinder | −0.25 ± 0.61 | −0.51 ± 0.74 | 0.26 | <0.0001 |
| 0 (−4:1) | −0.25 (−4:2.75) | (0.17 : 0.41) | ||
| SE | −0.63 ± 1.19 | −1.16 ± 1.42 | 0.53 | <0.0001 |
| −0.5 (−4:2.5) | −0.88 (−6.25 : 4.25) | (0.24 : 0.68) | ||
|
| ||||
| DED tests: | ||||
| Tear film break-up time: | <0.0001 | |||
| TBUT in seconds | 12.38 ± 1.78 | 8.93 ± 2.16 | 3.45 | |
| 12 (7 : 17) | 9 (2 : 15) | (4.26 : 3.12) | ||
| Abnormal TBUT test (<10 seconds) | 5 eyes (2.8%) | 336 eyes (60.3%) | <0.0001 | |
| Schirmer test: Schirmer test in mm | 19.57 ± 4.07 | 10.68 ± 4.37 | 8.89 | <0.0001 |
| 20 (8 : 29) | 9 (5 : 26) | (10.94 : 8.46) | ||
| Abnormal Schirmer test (<10 mm) | 5 eyes (2.8%) | 301 eyes (54%) | <0.0001 | |
| Slit-lamp examination: | ||||
| Conjunctival hyperemia (eye redness) | 11 eyes (6.3%) | 181 eyes (32.5%) | <0.0001 | |
| Watery/mucous discharge | 0 eyes (0%) | 3 eyes (0.5%) | <0.0001 | |
| Normal fundus examination: | 100% | 100% | ||
| Students/eyes documented with | ||||
| Diagnosed CVS cases | 0 cases (0%) | 557 cases (100%) | <0.0001 | |
| Reduced UDVA (worse than 0.00 logMAR) | 101 eyes (57.4%) | 409 eyes (73.4%) | 0.001 | |
| Reduced CDVA (worse than 0.00 logMAR) | 0 eyes (0%) | 0 eyes (0%) | 1.00 | |
| Diagnosed DED cases | 5 eyes (2.8%) | 336 eyes (60.3%) | <0.0001 | |
UDVA: uncorrected distance visual acuity; CDVA: corrected distance visual acuity; TBUT: tear film break-up time test; CVS: computer vision syndrome; DED: dry eye disease; SE: spherical equivalent; logMAR logarithm of the minimum angle of resolution.