Table 3. Changes of subjective symptoms of eye fatigue from baseline to 4 weeks after ingestion.
| Symptom | Group | n | Before | 4 weeks after | P valueb) | Variations |
|---|---|---|---|---|---|---|
| Mean + SE. | mean + SE. | mean + SE. | ||||
| Eye strain | Placebo | 24 | 4.292 + 0.095 | 3.708 + 0.185 | 0.012# | -0.583 + 0.199 |
| Supplement | 22 | 4.045 + 0.045 | 3.500 + 0.158 | 0.002## | -0.545 + 0.143 | |
| P valuea) | 0.049* | 0.235 | 0.815 | |||
| Ocular pain | Placebo | 5 | 4.200 + 0.200 | 3.200 + 0.374 | 0.125 | -1.000 + 0.316 |
| Supplement | 4 | 4.000 + 0.000 | 2.500 + 0.645 | 0.250 | -1.500 + 0.645 | |
| P value | 1.000 | 0.532 | 0.556 | |||
| Blurred vision | Placebo | 13 | 4.385 + 0.140 | 4.000 + 0.226 | 0.188 | -0.385 + 0.213 |
| Supplement | 12 | 4.083 + 0.083 | 3.083 + 0.313 | 0.016# | -1.000 + 0.302 | |
| P value | 0.160 | 0.033* | 0.090 | |||
| Teary eyes | Placebo | 10 | 4.100 + 0.100 | 3.400 + 0.267 | 0.063 | -0.700 + 0.260 |
| Supplement | 6 | 4.000 + 0.000 | 3.000 + 0.258 | 0.063 | -1.000 + 0.258 | |
| P value | 1.000 | 0.221 | 0.386 | |||
| Eye redness | Placebo | 6 | 4.000 + 0.000 | 3.500 + 0.224 | 0.250 | -0.500 + 0.224 |
| Supplement | 6 | 4.333 + 0.211 | 3.833 + 0.167 | 0.250 | -0.500 + 0.224 | |
| P value | 0.455 | 0.545 | 1.000 | |||
| Flickering vision | Placebo | 7 | 4.286 + 0.184 | 3.714 + 0.286 | 0.125 | -0.571 + 0.202 |
| Supplement | 6 | 4.000 + 0.000 | 3.667 + 0.333 | 0.625 | -0.333 + 0.333 | |
| P value | 0.462 | 1.000 | 0.796 | |||
| Double vision | Placebo | 7 | 4.429 + 0.202 | 4.429 + 0.202 | 1.000 | 0.000 + 0.218 |
| Supplement | 4 | 4.250 + 0.250 | 3.500 + 0.289 | 0.500 | -0.750 + 0.479 | |
| P value | 1.000 | 0.064 | 0.258 | |||
| Stiff shoulders or neck | Placebo | 20 | 4.350 + 0.109 | 4.300 + 0.179 | 1.000 | -0.050 + 0.135 |
| Supplement | 21 | 4.381 + 0.109 | 3.667 + 0.199 | 0.004## | -0.714 + 0.197 | |
| P value | 1.000 | 0.026* | 0.009** | |||
| Frustrate | Placebo | 6 | 4.167 + 0.167 | 3.667 + 0.494 | 0.500 | -0.500 + 0.428 |
| Supplement | 2 | 4.000 + 0.000 | 4.500 + 0.500 | 1.000 | 0.500 + 0.500 | |
| P value | 1.000 | 0.500 | 0.357 | |||
| Heaviness of head | Placebo | 5 | 4.200 + 0.200 | 3.600 + 0.510 | 0.500 | -0.600 + 0.400 |
| Supplement | 9 | 4.111 + 0.111 | 2.889 + 0.423 | 0.031# | -1.222 + 0.364 | |
| P value | 1.000 | 0.320 | 0.226 | |||
| Head ache | Placebo | 4 | 4.000 + 0.000 | 3.500 + 0.500 | 1.000 | -0.500 + 0.500 |
| Supplement | 5 | 4.200 + 0.200 | 3.600 + 0.600 | 0.500 | -0.600 + 0.510 | |
| P value | 1.000 | 0.992 | 0.825 | |||
| Difficult to see for small objects | Placebo | 17 | 4.471 + 0.125 | 4.235 + 0.202 | 0.219 | -0.235 + 0.136 |
| Supplement | 14 | 4.357 + 0.133 | 4.143 + 0.206 | 0.375 | -0.214 + 0.155 | |
| P value | 0.717 | 0.741 | 0.963 | |||
| Difficult to focus on objects | Placebo | 9 | 4.222 + 0.147 | 3.667 + 0.408 | 0.313 | -0.556 + 0.377 |
| Supplement | 10 | 4.400 + 0.163 | 3.500 + 0.269 | 0.031# | -0.900 + 0.277 | |
| P value | 0.628 | 0.539 | 0.397 | |||
| Dazzle vision | Placebo | 10 | 4.100 + 0.100 | 3.700 + 0.367 | 0.500 | -0.400 + 0.340 |
| Supplement | 11 | 4.273 + 0.141 | 3.727 + 0.195 | 0.125 | -0.545 + 0.247 | |
| P value | 0.586 | 0.744 | 0.641 | |||
| Difficult to see in low light condition | Placebo | 9 | 4.111 + 0.111 | 2.889 + 0.389 | 0.016# | -1.222 + 0.364 |
| Supplement | 8 | 4.500 + 0.189 | 3.500 + 0.378 | 0.063 | -1.000 + 0.378 | |
| P value | 0.131 | 0.508 | 0.616 |
Subjects that scored four or more in each symptom at the baseline were analyzed. Values were expressed as mean±SE.
a) Comparison of differences between placebo and multiple dietary supplement groups was assessed by Wilcoxon rank sum test (**: p<0.01, *: p<0.05).
b) Inter-group comparison was assessed by the Wilcoxon singed rank test (##: p<0.01, #: p<0.05).