Table 4:
Predictors of Discordance of Algorithms – Bivariate Analysis
| Variable | VF either progressing or stable in 4 of 6 algorithms (n = 11929) |
VF progressing in 3 algorithms and stable in 3 algorithms (n = 1227) |
P-value |
|---|---|---|---|
| Institution | |||
| 1 | 5668 (90.9%) | 564 (9.1%) | P < 0.01 |
| 2 | 815 (94.5%) | 47 (5.5%) | |
| 3 | 3369 (89.6%) | 391 (10.4%) | |
| 4 | 795 (87.7%) | 111 (12.3%) | |
| 5 | 1282 (91.8%) | 114 (8.2%) | |
| Eye | |||
| Right | 5903 (91.1%) | 576 (8.9%) | 0.09 |
| Left | 6026 (90.3%) | 651 (9.7%) | |
| Initial Mean Deviation (mean +/− SD) | −4.5 +/− 5.7 | −8.0 +/− 6.2 | P < 0.01 |
| Initial Mean Deviation (categorical) | |||
| ≥ −6 | 8713 (93.9%) | 569 (6.1%) | P < 0.01 |
| −6 < MD < −12 | 1800 (83.9%) | 346 (16.1%) | |
| ≤ −12 | 1416 (81.9%) | 312 (18.1%) | |
| Follow up (years) | 6.3 +/− 2.5 | 6.6 +/− 2.5 | P < 0.01 |
| Follow up (years - categorical) | |||
| ≤ 5 | 3910 (91.6%) | 358 (8.4%) | P = 0.03 |
| 6-10 | 6797 (90.3%) | 729 (9.7%) | |
| >10 | 1222 (89.7%) | 140 (10.3%) | |
| Age (years) | 63.4 +/− 12.2 | 68.1 +/− 11.3 | P < 0.01 |
| Age (years - categorical) | |||
| 18 – 40 | 476 (95.0%) | 25 (5.0%) | P < 0.01 |
| 40 – 60 | 3854 (93.8%) | 256 (6.2%) | |
| 60 – 80 | 6785 (89.4%) | 804 (10.6%) | |
| >80 | 814 (85.1%) | 142 (14.9%) | |
| Number of Fields (mean +/− SD) | 6.9 +/− 2.4 | 7.3 +/− 2.7 | P < 0.01 |
| Fields per year (mean +/− SD) | 1.2 +/− 1.2 | 1.3 +/− 2.2 | P = 0.11 |
| Number of Fields (categorical) | |||
| 5 | 4301 (92.1%) | 368 (7.9%) | P < 0.01 |
| 6-10 | 6634 (90.2%) | 717 (9.8%) | |
| >10 | 994 (87.5%) | 142 (12.5%) | |
| Fields per year (categorical) | |||
| ≤1 | 4662 (91.0%) | 460 (9.0%) | P = 0.53 |
| 1-2 | 6433 (90.5%) | 676 (9.5%) | |
| >2 | 834 (90.2%) | 91 (9.8%) |
VF = Visual Field, SD = Standard Deviation