Table 6a.
Comparison of Manual Refraction with Auto Refraction and Supplemental Manual Refraction Visual Acuity Letter Score
| MR-EVAsupl - MR-EVA | AR-EVA - MR-EVA | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Overall | Average MR-EVA | Overall | Average MR-EVA | |||||||
| ≥20/20 (≥84) |
20/25-20/32 (83-74) |
20/40-20/80 (73-54) |
≤20/100 (≤53) |
≥20/20 (≥84) |
20/25-20/32 (83-74) |
20/40-20/80 (73-54) |
≤20/100 (≤53) |
|||
| N | 878 | 158 | 279 | 307 | 134 | 878 | 158 | 279 | 307 | 134 |
| Letter Difference*- Median (5th, 95th percentiles) | 0 (−5, +7) | 0 (−3, +4) | 0 (−4, +5) | +1 (−7, +9) | 0 (−7, +9) | −1 (−17, +7) | −2 (−15, +5) | −2 (−15, +6) | −1 (−22, +10) | 0 (−12, +9) |
|
Letter Difference Group - N (%) |
||||||||||
| ≤ −15 | 5 (1%) | 0 | 0 | 4 (1%) | 1 (1%) | 56 (6%) | 8 (5%) | 14 (5%) | 28 (9%) | 6 (4%) |
| −14 to −10 | 9 (1%) | 0 | 1 (<1%) | 4 (1%) | 4 (3%) | 49 (6%) | 8 (5%) | 12 (4%) | 21 (7%) | 8 (6%) |
| −9 to −5 | 38 (4%) | 2 (1%) | 7 (3%) | 17 (6%) | 12 (9%) | 142 (16%) | 29 (18%) | 41 (15%) | 46 (15%) | 26 (19%) |
| −4 to +4 | 728 (83%) | 151 (96%) | 249 (89%) | 230 (75%) | 98 (73%) | 545 (62%) | 105 (66%) | 194 (70%) | 168 (55%) | 78 (58%) |
| +5 to +9 | 77 (9%) | 5 (3%) | 20 (7%) | 38 (12%) | 14 (10%) | 63 (7%) | 8 (5%) | 16 (6%) | 28 (9%) | 11 (8%) |
| +10 to +14 | 12 (1%) | 0 | 0 | 9 (3%) | 3 (2%) | 10 (1%) | 0 | 1 (<1%) | 6 (2%) | 3 (2%) |
| ≥+15 | 9 (1%) | 0 | 2 (1%) | 5 (2%) | 2 (1%) | 13 (1%) | 0 | 1 (<1%) | 10 (3%) | 2 (1%) |
|
Absolute Value of the Letter Difference * - Median (5th, 95th percentiles) |
2 (0, 9) | 1 (0, 4) | 2 (0, 7) | 2 (0, 11) | 2(0, 11) | 4 (0, 20) | 3 (0, 15) | 3 (0, 16) | 4 (0, 24) | 4 (0, 16) |
| < 5 - N(%) | 728 (83%) | 151 (96%) | 249 (89%) | 230 (75%) | 98 (73%) | 545 (62%) | 105 (66%) | 194 (70%) | 168 (55%) | 78 (58%) |
| <10 - N(%) | 843 (96%) | 158 (100%) | 276 (99%) | 285 (93%) | 124 (93%) | 750 (85%) | 142 (90%) | 251 (90%) | 242 (79%) | 115 (86%) |
| <15 - N(%) | 864 (98%) | 158 (100%) | 277 (99%) | 298 (97%) | 131 (98%) | 809 (92%) | 150 (95%) | 264 (95%) | 269 (88%) | 126 (94%) |
|
Coefficient of
Repeatability |
9 | 5 | 7 | 13 | 11 | 18 | 16 | 14 | 22 | 15 |
*
Supplemental MR EVA - MR EVA and Auto Refraction EVA - Manual Refraction EVA, respectively
**
Absolute Value of the Difference
MR-EVA= Manual refraction Electronic Early Treatment Diabetic Retinopathy Study Visual Acuity Test letter score; AR-EVA= Autorefraction Electronic Early Treatment Diabetic Retinopathy Study Visual Acuity Test letter score; MR-EVAsupl= Supplemental Manual refraction Electronic Early Treatment Diabetic Retinopathy Study Visual Acuity Test letter score