Table 1. Frequency Distributions of Refractive Error Risk Factors in 3 to 6 Years-Old Children with and without Strabismus in the Nanjing Pediatric Vision Project.
| Risk factor | Esotropia | No Esotropia | Exotropia | No Exotropia | P Value § | |
|---|---|---|---|---|---|---|
| (N = 45), n(%)* | (N = 5786), n(%)* | P Value§ | (N = 270), n(%)* | (N = 5561), n(%)* | ||
| Age group | ||||||
| 3 y | 3(0.5) | 660(99.5) | 0.137 | 25(3.8) | 638(96.2) | 0.02 |
| 4 y | 17(0.7) | 2466(99.3) | 97(3.9) | 2386(96.1) | ||
| 5 y | 19(0.8) | 2325(99.2) | 133(5.7) | 2211(94.3) | ||
| 6 y | 6(1.8) | 335(98.2) | 15(4.4) | 326(95.6) | ||
| Sex | ||||||
| Male | 25(0.8) | 3093(99.2) | 0.881 | 147(4.7) | 2971(95.3) | 0.755 |
| Female | 20(0.7) | 2693(99.3) | 123(4.5) | 2590(95.5) | ||
| SE anisometropia(D) | ||||||
| <0.50 | 23(0.4) | 5573(99.6) | <0.001 | 195(3.5) | 5401(96.5) | <0.001 |
| 0.50-<1.00 | 11(7.5) | 135(92.5) | 56(38.4) | 90(61.6) | ||
| > = 1.00 | 11(12.4) | 78(87.6) | 19(21.3) | 70(78.7) | ||
| J0 anisometropia(D) | ||||||
| <0.25 | 36(0.6) | 5612(99.4) | <0.001 | 213(3.8) | 5435(96.2) | <0.001 |
| 0.25-<0.50 | 7(5.5) | 120(94.5) | 45(35.4) | 82(64.6) | ||
| > = 0.50 | 2(3.6) | 54(96.4) | 12(21.4) | 44(78.6) | ||
| J45 anisometropia(D) | ||||||
| <0.25 | 40(0.7) | 5673(99.3) | <0.001 | 238(4.2) | 5475(95.8) | <0.001 |
| 0.25-<0.50 | 4(5.1) | 74(94.9) | 25(32.1) | 53(67.9) | ||
| > = 0.50 | 1(2.5) | 39(97.5) | 7(17.5) | 33(82.5) | ||
| SE refractive error(D) † | ||||||
| <-1.00 | 1(4.3) | 22(95.7) | <0.001 | 4(17.4) | 19(92.6) | <0.001 |
| -1.0-<0.00 | 0(0) | 21(100) | 7(33.3) | 14(66.7) | ||
| 0.00-<1.00 | 16(0.3) | 5334(99.7) | 74(1.4) | 5276(98.6) | ||
| 1.00-<2.00 | 6(2.4) | 249(97.6) | 138(54.1) | 117(45.9) | ||
| 2.00-<3.00 | 8(6.7) | 112(93.3) | 35(29.2) | 85(70.8) | ||
| 3.00-<4.00 | 2(7.1) | 26(92.9) | 9(32.1) | 19(67.9) | ||
| 4.00-<5.00 | 2(12.5) | 14(87.5) | 2(12.5) | 14(87.5) | ||
| > = 5.00 | 10(55.6) | 8(44.4) | 1(5.6) | 17(94.4) | ||
| Astigmatism (D) † | ||||||
| <0 | 14(4.4) | 307(95.6) | <0.001 | 131(40.8) | 190(59.2) | <0.001 |
| 0-<0.50 | 21(0.4) | 5376(99.6) | 114(2.1) | 5283(97.9) | ||
| 0.5-<1.0 | 7(15.2) | 39(84.8) | 18(39.1) | 28(60.9) | ||
| > = 1.0 | 3(4.5) | 64(95.5) | 7(10.4) | 60(89.6) |
D = diopters; J0 = power in the vertical or horizontal meridian; J45 = power in the oblique meridian; SE = spherical equivalent.
*Percentage of participants with stated outcome status.
§Chi square or Fisher exact test where applicable.
†Level of refractive error defined by the less hyperopic eye for SE refractive error, and the less astigmatic eye for astigmatic refractive error.