A | B | C | ||
---|---|---|---|---|
Refractive error | Junghans et al (n=2490), n (%) | SN (n=228), n (%) | LD (n=172), n (%) | Comparison of A vs C (χ2 test) |
Hyperopia (0 to +1.50 D) | 2216 (89) | 119 (52.2) | 97 (56.4) | p<0.001 |
Hyperopia >1.50 D | 192 (7.7) | 61 (26.8) | 49 (28.5) | p<0.001 |
Hyperopia > +2.0 D | 50 (2) | 44 (19.3) | 37 (21.5) | p<0.001 |
Myopia ≥ −0.50 D | 132 (5.3) | 22 (9.6) | 17 (9.9) | p=0.048 |
Myopia < −0.50 D (not included in calculations by Junghans et al) | – | 26 (11.4) | 9 (5.2) | |
Myopia ≥ −2.0 D | 27 (1.1) | 10 (4.4) | 8 (4.7) | p=0.028 |
Spherical errors between −1.75 and +2.00 D | 2415 (97) | 177 (77.6) | 132 (76.7) | p<0.001 |
Astigmatism ≤0.25 DC | 1768 (71) | 117 (51.3) | 89 (51.7) | p<0.001 |
Astigmatism −0.25 to −1.00 DC | 672 (27) | 88 (38.6) | 59 (34.3) | p=0.050 |
Astigmatism >1.00 DC | 50 (2) | 50 (21.9) | 39 (22.7) | p<0.001 |
‘A’ refers to the Junghans et al data.10 ‘B’ refers to the total population of children with special needs. ‘C’ refers to the LD subgroup within the special needs cohort.
DC, dioptres cylinder; LD, learning disability; SN, special needs.