From my understanding it's better that the bone age is less than the CAH child's chronological age, to allow their bones the maximum growing time. Once the bones are matured, there's no going back...in other words their growth is stunted, and in the end they are shorter than they were genetically meant to be. However, 1.5yrs difference sounds like alot to me. How does her Endo feel about it? My 14yr old son just had his bone age Xray done, we will get the results at his visit the end of May. He has always been within 1yr. I can't help you out with the hormone test question, sorry, I hope someone else can.