For a late bloomer using the height predictors, do I use my actual age or my bone age?

Question:

On the website, there is a link to a height predictor using sitting height. I am 16 and 9 months and I am 5’4. My doctor said my bone age is delayed so it is around the early months of 15. My doctor said I was just a late bloomer and would reach an adult height around 5’8.

The problem is, when I use this website and put my actual birthday, it says my maturity as “late” but it only says I’ll grow 1.6 inches. But when I put the birthday of my bone age (1 year + 5 months) I get 5’7/5’8. So for this predictor, when it says date of birth, should I put the date of birth of my bone age?

Answer:

When the height prediction formulas were developed, the authors tried to make them simple to use. Thus, they will use a person’s age as an approximation of his development. Some will also use a person’s weight to get a bit better approximation. These work well when a person is developing at close to the average time, but it breaks down for early developers and late developers. By using your bone age test result, you are correcting the approximation of your development. Thus, what you did was reasonable.