Bayley-Pinneau combines current stature with skeletal age from a hand-wrist radiograph to estimate adult height. It does not reveal a fixed future height. The result depends on the reference sample, measurement quality and bone-age interpretation.
This page is educational. Whether an X-ray is appropriate and how skeletal age should be interpreted are clinical decisions for a pediatrician or pediatric endocrinologist.
What the method does
The original tables estimate the proportion of adult stature attained at a given skeletal age assessed with the Greulich-Pyle hand standards. That proportion is read alongside current height. The foundational source is the 1952 Bayley and Pinneau paper.
Input quality matters:
- Height should be measured with a calibrated stadiometer and standard technique.
- Bone age needs an appropriate image and a trained reader.
- Chronological age, sex and maturation context must be considered together.
- The output should be shown with uncertainty, not as one guaranteed number.
Why it is not a stand-alone decision tool
Prediction models can systematically over- or underestimate adult height in different populations. A longitudinal comparison during normal puberty found that outlying predictions remain possible and urged caution in counselling. Read the method comparison.
Studies in constitutional delay of growth and puberty also show that Bayley-Pinneau can overestimate adult height in some delayed maturers. "Delayed bone age means definite extra growth" is therefore not a safe automatic conclusion. Review the validation cohort.
A safer sequence for families
- Place current height on an age- and sex-specific percentile or z-score chart.
- Read annual growth velocity and curve direction, not one measurement.
- Estimate the genetic target range from parental heights.
- If bone age was clinically indicated, use Bayley-Pinneau as added context.
- Treat material disagreement between methods as a reason for clinical review.
Our height-prediction guide compares Neyzi percentiles, Mid-Parental Height, Khamis-Roche and bone-age methods in one framework. A prediction must never be used to select, rank or exclude a child from sport.
When to seek clinical review
Seek pediatric or pediatric-endocrinology review for a marked downward crossing of the growth curve, unexpectedly low growth velocity, puberty-timing concerns, signs of chronic illness, or substantial disagreement between methods. Online prediction must not carry an urgent or diagnostic decision by itself.