Understanding the Prediction Error in Height Calculations
Understanding the Prediction Error in Height Calculations
The Khamis-Roche method is widely used to predict adult height based on current measurements and parental heights. However, the prediction error changes depending on the stage of growth. Below is an overview of the typical error margins:
| Growth Stage (Approx. % of Adult Height) | Boys Error | Girls Error | Notes |
|---|---|---|---|
| Pre-Puberty (≈70% of adult height) | ±5.0 cm (≈3–4%) | ±4.0 cm (≈3%) | Early predictions are less reliable due to upcoming growth spurts. |
| Mid-Puberty (≈80–85% of adult height) | ±6.0 cm (up to ≈4%) | ±5.0 cm (≈3–4%) | Highest uncertainty during rapid changes. |
| Late Puberty (≈90–95% of adult height) | ±2–3 cm (≈1–2%) | ±2.0 cm (≈1%) | Greater accuracy as growth slows. |
| Near Adult (>97% of adult height) | ±1–2 cm | ±1 cm | Very precise predictions as growth nears completion. |
How the Error Is Calculated
For example, if a boy at 70% of his predicted adult height (180 cm) has an estimated error of 3.5%, the absolute error is calculated as:
Error (cm) = (3.5 / 100) * 180 ≈ 6.3 cm