Table 6 Prevalence rates of different types of astigmatism (Astigmatism≤-0.75 D) (N = 71,838)

Age (year)

7

4705 (69.6)

1621 (24.0)

264 (3.9)

171 (2.5)

1000.100

< 0.001

8

5164 (67.8)

2011 (26.4)

275 (3.6)

171 (2.2)

9

5197 (67.7)

1998 (26.0)

272 (3.5)

211 (2.7)

10

5145 (67.3)

1997 (26.1)

290 (3.8)

213 (2.8)

11

5533 (66.1)

2276 (27.2)

336 (4.0)

221 (2.6)

12

4891 (62.9)

2258 (29.0)

360 (4.6)

271 (3.5)

13

3615 (60.6)

1796 (30.1)

303 (5.1)

251 (4.2)

14

3221 (59.4)

1657 (30.6)

301 (5.6)

240 (4.4)

15

2544 (55.6)

1542 (33.7)

259 (5.7)

228 (5.0)

16

1889 (56.5)

981 (29.3)

255 (7.6)

220 (6.6)

17

1919 (57.5)

979 (29.3)

224 (6.7)

218 (6.5)

18

1473 (59.7)

666 (27.0)

197 (8.0)

131 (5.3)

19

597 (68.0)

165 (18.8)

69 (7.9)

47 (5.4)

Gender

Male

22,763 (62.2)

10,843 (29.6)

1664 (4.5)

1337 (3.7)

132.507

< 0.001

Female

23,130 (65.7)

9104 (25.8)

1741 (4.9)

1256 (3.6)

Nationality

Han

27,193 (60.4)

14,635 (32.5)

1590 (3.5)

1603 (3.6)

2308.208

< 0.001

Uyghur

9395 (73.6)

1985 (15.6)

902 (7.1)

481 (3.8)

Kazakhs

986 (66.0)

371 (24.8)

86 (5.8)

52 (3.5)

Kyrgyz

3582 (67.9)

897 (17.0)

570 (10.8)

228 (4.3)

Hui

3496 (66.0)

1474 (27.8)

175 (3.3)

153 (2.9)

Others

1241 (62.6)

585 (29.5)

82 (4.1)

76 (3.8)

Education stage

Primary school

30,689 (66.7)

12,178 (26.5)

1818 (4.0)

1297 (2.8)

748.608

< 0.001

Junior high school

9501 (59.1)

5004 (31.1)

867 (5.4)

696 (4.3)

High school

5703 (58.3)

2765 (28.2)

720 (7.4)

600 (6.1)

Spherical equivalent (SE)

SE<-0.50 D

18,545 (57.1)

10,894 (33.5)

1631 (5.0)

1427 (4.4)

2215.31

< 0.001

-0.50 D ≤ SE ≤ + 0.50 D

26,076 (71.6)

7898 (21.7)

1503 (4.1)

951 (2.6)

SE > + 0.50 D

1272 (43.7)

1155 (39.6)

271 (9.3)

266 (7.4)

Total

45,893 (63.9)

19,947 (27.8)

3405 (4.7)

2593 (3.6)