Mid-Parental (Target) Height

Why use it

A child's height is best interpreted against the family's height: a child on a low centile may be growing appropriately for short parents, while a child on an average centile may be below the expected range for tall parents. NICE NG75 uses the distance between the child's length/height centile and the mid-parental centile as one of the features that should raise awareness of undernutrition or a growth disorder.

About

The mid-parental height (target height) estimates a child's genetic height potential from the measured heights of both biological parents. The parents' mean height is adjusted for the average adult sex difference of 13 cm: for boys, (father + mother + 13) / 2; for girls, (father + mother − 13) / 2. The range of ±8.5 cm around the target approximates the 3rd to 97th centile of the expected adult height. The method was described by Tanner, Goldstein and Whitehouse (Arch Dis Child 1970) and remains the usual reference in growth assessment.

When to use

• Assessment of short or tall stature
• Interpreting a length/height centile that differs from the weight centile
• Follow-up of growth in children with genetic, endocrine or chronic conditions

Formula

Pearls & pitfalls

• Measured parental heights are preferable to reported heights.
• The formula assumes both parents are biological parents with normal growth; it is less informative when a parent has a growth disorder.
• The ±8.5 cm range corresponds to roughly the 3rd–97th centile of the expected adult height for the family.
• Target height predicts adult height, not current height: compare it with the child's centile, not with the child's height in centimetres.

Next steps

Compare the child's current height centile with the centile that the target height occupies on the adult end of the same chart. A child growing well below the familial range warrants assessment of growth (growth velocity, puberty, bone age and the clinical context, as appropriate).

Evidence

Formula and range: Tanner JM, Goldstein H, Whitehouse RH, Arch Dis Child 1970;45:755-62, as quoted by Ciancia et al., BMC Pediatr 2025 ("The so-calculated TH has a range of ±8.5 cm"). NICE NG75 (2017), recommendation 1.2.3, cites the comparison between length/height and mid-parental centile.

References

1. Tanner JM, Goldstein H, Whitehouse RH. Standards for children's height at ages 2-9 years allowing for heights of parents. Arch Dis Child. 1970;45(244):755-762. — link
2. Ciancia S, et al. BMC Pediatrics. 2025 (open access; quotes the Tanner formula and the ±8.5 cm range). — link
3. National Institute for Health and Care Excellence. Faltering growth: recognition and management of faltering growth in children. NICE guideline NG75. 2017. — link