| OG tube insertion distance | = 13.3 cm + 0.19(HTcm) if 1 to 28 months of age |
| = 16.8 cm + 0.19(HTcm) if 29 to 100 months of age | |
| = 15.1 cm + 0.22(HTcm) if > 100 months of age | |
| NG tube insertion distance | = 14.8 cm + 0.19(HTcm) if 1 to 28 months of age |
| = 18.3 cm + 0.19(HTcm) if 29 to 100 months of age | |
| = 16.6 cm + 0.22(HTcm) if > 100 months of age |