DETERMINATION OF SEX FROM MASTOID PROCESS BY DISCRIMINANT FUNCTION ANALYSIS

Sex determination is vital for the identification of an individual. Often fragmentary remains are available for forensic identification making sex determination difficult. The mastoid region, a fragmentary piece of skull, is ideal for studying sexual dimorphism as it is resistant to damage due to its anatomical position at the base of skull. The skull measurements vary significantly in different ethnic groups and the discrimination models for Indian populations are rare. In the present study, 60 adult human skulls of North Indian individuals were studied to determine accuracy of mastoid process in sex determination. Mastoid length, breadth and antero-posterior diameter of the mastoid process were measured to calculate the size of mastoid process. Discriminant function analysis revealed that mastoid process correctly classified the sex in 76.7% of the subjects and mastoid length was found to be the best determinant for sex although the classification rate dropped to 66.7%. A discriminant function equation specific for North Indian population has also been derived from mastoid variables.