Table 2.
Baseline Clinical Measures and Slopes Measuring Change Over Seven Years of Follow-up for 925 CLEK Participantsa
| Variable | N | Baseline Mean(SD or N [%]) | N | Slope Mean (SD or N [%]) |
|---|---|---|---|---|
| Visual acuity (letters correct, high contrast) | ||||
| Entrance binocular | 924 | 52.2 (6.65) | 919 | −0.15 (1.18) |
| Baseline visual acuity worse than 20/40 | 33 | 3.6% | ||
| Loss of ≥ 10 letters during follow-up | 170 | 18.5% | ||
| Corneal curvature (diopters, steep keratometry ) | ||||
| Average of left and right eyes | 917 | 50.5 (4.63) | 918 | 0.16 (0.48) |
| Baseline steep keratotomy ≥ 52 D | 280 | 30.3% | ||
| Increase of >3.00 D during follow-up | 115 | 12.4% | ||
| Corneal scarring present (at baseline) | 283 | 30.6% | ||
| Incident scar during follow-up | 149 | 16.1% | ||
| Penetrating keratoplasty during follow-up | 52 | 5.6% | ||
| NEI-VFQ scale scores | ||||
| General vision | 924 | 74.7 (14.6) | 924 | −0.06 (3.00) |
| Ocular pain | 925 | 75.6 (17.2) | 925 | 0.23 (3.79) |
| Near activities | 925 | 79.1 (18.2) | 925 | −0.24 (2.84) |
| Distance activities | 925 | 78.4 (17.3) | 925 | −0.03 (2.71) |
| Social function | 925 | 91.7 (14.4) | 925 | −0.17 (2.59) |
| Mental health | 925 | 74.9 (21.2) | 925 | 0.48 (3.50) |
| Role difficulties | 924 | 81.9 (21.9) | 924 | −0.23 (3.76) |
| Dependency | 923 | 94.4 (13.1) | 923 | −0.55 (2.95) |
| Driving | 886 | 80.4 (17.0) | 883 | −0.12 (2.91) |
| Color vision | 924 | 96.9 (11.1) | 923 | −0.19 (2.28) |
| Peripheral vision | 924 | 81.9 (21.9) | 923 | −0.44 (3.30) |
Abbreviation: SD, standard deviation
a
Where the “N” does not equal 925, this indicates missing data for that measure for some participants. Slopes represent expected change for one year.