Reported frequency of a two-line reduction in VA
| Author(s) | No. of eyes | VA | Mean follow-up (months) | % Worse |
| Rotchford (these data) | 49 | ≥20/60 | 60.0 | 30.6% |
| Egbert et al9 | 19 | ≥20/60 | 13.2 | 5%* |
| Wilensky and Kammer10 | 21 | ≥20/80 | 40.7 | 28.6% |
| Ansari and Gandhewar11 | 23 | ≥20/120 | 12.1 | 13.0%* |
| Bloom et al8 | 68† | ≥20/200 | 21.7 | 10.3%* |
| Schuman et al7 | 36 | ≥20/200 | >12 | 47.2% |