Abstract: Objective To research the connection of the minor′s bone age and chronological age and age for penal responsibility, to discuss the application of Gu′s Atlas and Li Guozhen′s Percent Numeration to measure the bone age in the cases of immature criminals and the applying value. Methods 33 healthy youths,12-19 years old, were selected, whose left wrists were photographed with X-rays. According to the radiographic appearance of the maturity indicators, the bone age of every person was determined respectively by the Gu′s Atlas and Li Guozhen′s Percent Numeration, and then compared with his/her chronological age. CMH test and Pearson test were used to evaluate precision and accuracy on concluding the immature age for penal responsibility. Results Li Guozhen′s Percent Numeration was more precise than Gu′s Atlas on extrapolating the chronological age of the youth, P<0.005. On extrapolating the age for penal responsibility, the accuracy of the former was 90.91%, and the latter was 78.79%, but the statistic result did not show significant difference (P>0.1). Conclusion Both measurements can apply in determining the criminal cases of immature youths.

Key words: forensic anthropology, bone age, chronological age, age for penal responsibility