| Single-letter scoring | Mean difference (SE) logMAR | 95% CI mean difference, logMAR | SD differences logMAR | TRV (95% confidence limits for agreement) logMAR | Min/max difference logMAR |
| ETDRS-ETDRS | 0.01 (0.01) | −0.01, 0.02 | 0.06 | ±0.12 | −0.14, 0.16 |
| COMPlog-COMPlog | 0.02 (0.01) | 0.00, 0.04 | 0.06 | ±0.12 | −0.08, 0.14 |
| ETDRS-COMPlog | 0.01 (0.01) | −0.01, 0.03 | – | – | – |