Why are my predictions so far off?

Last updated on July 1, 2023



At 2 years old I was 3’4″. Then at 6, I was 4’3″, 47 lbs. My father is 5’10.5″ and my mother is 5’5.5″.

The doctor used the Khamis-Roche method to predict my height and he said 6’5″. 

I’m 16 now and 5’10”. I started puberty at 12, but never had a growth spurt; I’ve been a consistent grower. My father kept growing until 22.

My question is: Why was my prediction so far off despite the high accuracy of the method used? I’m not done growing as I’ve been growing exactly 1.5 inches a year for the last 6 years. But my Tanner stage says 3.6 and it’s been like that for 2 years now. Does this mean I have extended puberty? My physical features haven’t changed besides height and penis size. Will I reach the predicted height?


Since you haven’t finished growing, why do you conclude that the predictions are far off?

Most boys have a burst of growth which is referred to as a growth spurt, but there are some boys who just grow steadily for a longer period of time. It sounds like you are in the steady group.


So it’s possible to grow past age 16? I read online you will only grow 2 inches after age 16. 

I have another question if possible. Is it normal if my pubic hair still has the same distribution and thickness as at age 12 despite the difference in penile size?

God bless you and thank you for your response.


Clearly, it is possible to grow after 16. After all, your dad told you that he continued growing until he was 22. Growth is not based strictly on age. The body has its own clock. You won’t stop growing until you reach stage 5. And you haven’t even reached stage 4 yet.

The distribution of pubic hair does vary with different boys. That is why the calculator shows several examples.