Fissure visibility in different age groups (all three radiologists in agreement)
| Age group | Right minor fissure (%) | Right major fissure (anterior) (%) | Right major fissure (posterior) (%) | Left major fissure (anterior) (%) | Left major fissure (posterior) (%) | All fissure segments (%) |
| 0–2 months | 6/9 (67) | 7/9 (78) | 7/9 (78) | 8/9 (89) | 8/9 (89) | 36/45 (80) |
| 5–6 months | 13/16 (94) | 16/16 (100) | 15/16 (94) | 15/16 (94) | 15/16 (94) | 74/80 (92) |
| 7–9 months | 13/15 (87) | 15/15 (100) | 15/15 (100) | 14/15 (93) | 14/15 (93) | 71/75 (95) |
| All age groups | 32/40 (80) | 38/40 (95) | 37/40 (93) | 37/40 (93) | 37/40 (93) | 181/200 (91) |