Demonstration of the number of images considered unsatisfactory in relation to the total number of each image viewed for each transmission format
| Direct video | Three channels | Two channels | One channel | |
|---|---|---|---|---|
| Cross sectional | 5/160 (3%) | 9/160 (6%) | 13/160 (8%) | 32/160 (20%) |
| M mode | 0/40 (0%) | 0/40 (0%) | 0/40 (0%) | 0/40 (0%) |
| Colour Doppler | 2/80 (3%) | 2/80 (3%) | 2/80 (3%) | 3/80 (4%) |
| Spectral Doppler | 0/48 (0%) | 0/48 (0%) | 1/48 (2%) | 0/48 (0%) |