Table 1.
Total prevalence of myopia and prevalence of myopia stratified by sex and age
| Age (y) | Prevalence of Myopia (N1/N2) | χ2 | P value | ||
|---|---|---|---|---|---|
| Total | Boys | Girls | |||
| 3 | 1.9 % (3/159) | 1.2 % (1/80) | 2.5 %(2/79) | 0.353 | 0.553 |
| 4 | 2.6 % (6/235) | 3.6 % (5/139) | 1.0 % (1/96) | 1.49 | 0.22 |
| 5 | 1.7 % (4/234) | 2.3 % (3/128) | 0.9 % (1/106) | 0.692 | 0.406 |
| 6 | 8.6 % (199/2304) | 7.8 % (92/1173) | 9.5 % (107/1131) | 1.91 | 0.167 |
| 7 | 14.5 % (427/2936) | 15.1 % (237/1569) | 13.9 % (190/1367) | 3.447 | 0.07 |
| 8 | 25.9 % (678/2621) | 25.3 % (346/1365) | 26.4 % (332/1256) | 0.402 | 0.526 |
| 9 | 37.2 % (904/2431) | 34.7 % (432/1245) | 39.8 % (472/1186) | 6.76 | 0.009* |
| 10 | 48.7 % (1138/2336) | 45.9 % (546/1190) | 51.7 % (592/1146) | 7.795 | 0.005* |
| 11 | 56.5 % (1248/2210) | 53.4 % (611/1145) | 59.8 % (637/1065) | 9.338 | 0.002* |
| 12 | 66.2 % (1075/1623) | 62.2 % (532/855) | 70.7 % (543/768) | 13.0 | < 0.001** |
| 13 | 72.1 % (1031/1429) | 69.1 % (509/737) | 75.4 % (522/692) | 7.21 | 0.007* |
| 14 | 74.9 % (702/937) | 71.1 % (350/492) | 79.1 % (352/445) | 7.89 | 0.005* |
N: number, N1: the number of myopic children, N2: the total number of children, * represents P < 0.05, ** represents P < 0.001