The standard way of predicting the height of children is not as accurate as first thought, says research.
Their survey of more than 4,200 children found that while the system worked reasonably well for children whose parents were of average height, when applied to more extreme cases, the system was "misleading".
In fact, children of very tall parents were quite likely to be shorter than the average worked out for them, and children of extremely short parents likely to prove slightly taller. Children's heights often give a clue to any underlying health problem they may have. If a child is too short, it may be due to serious underlying disease, malnutrition or even abuse, so it is important that doctors correctly identify the cause.
The researchers noted: "We suggest that few paediatricians are aware of the need to allow for regression and these data demonstrate that doing so might substantially alter their interpretation of a child's growth pattern."