Table 2 Summary results on precision (repeatability) of automatic estimation of endothelial cell density.
| Manual | Automatic | |||
|---|---|---|---|---|
| SD (%) | Range (%) | SD (%) | Range (%) | |
| Mean | 68 (3) | 95 (4) | 62 (3) | 163 (7) |
| SD | 59 (2) | 83 (3) | 30 (1) | 86 (4) |
| Min | 0 (0) | 0 (0) | 7 (0) | 13 (1) |
| Max | 270 (11) | 382 (16) | 156 (7) | 455 (21) |
For the 200× image of each cornea (Manual), standard deviation (SD) and range were derived from the manual densities obtained by two experts. For all 100× images of each cornea (Automatic), automatic densities were obtained and then their standard deviation and range were computed. Per cent values for all quantities are also reported. For all quantities, average, SD, minimum and maximum values are reported over the 200 corneas. All quantities are in cells/mm2, except when “%” is indicated.