The accuracy and precision of the "Demirjian system" when used for age determination in Chinese children.

The accuracy and precision of a method devised for estimation of chronological age based on tooth formation (Demirjian et al 1973) using its latest standards (Demirjian 1982, 1986) were investigated using 204 panelipses obtained from a randomised sample of 5-7 year old Chinese children. The precision was found to be high but the accuracy was low. The mean difference between dental age and true age of the Chinese children was 11 and 7 months in boys and girls, respectively. The 95 per cent confidence interval was about +/- 15 months in both sexes. The results indicate that Demirjian's method cannot be used to accurately estimate chronologic age of Chinese children of this age group.