Sexual Dimorphism of North Indian Crania and its Forensic Application

Abstract

Sex determination is a major challenge for forensic anthropologist in the medicolegal context. It constitutes initial step in personal identification from skeletal remains and is indispensable further to define age and stature of the deceased. There have been several studies on sex determination from different skeletal parts using osteometric and morphological approaches. Degree of sexual dimorphism and osteological standards vary across time and space. This requires need for valid population specific standards for sex determination. Skull is considered as the most discriminating after pelvis among skeletal parts.As in India, the population varies to a large extent, assortment of skeleton cannot be made representing the whole country in general; therefore, regional studies must be promoted. Each population group thus needs its own sex specific osteometric standards. No large scale study on North Indian skull was conducted. The aim of the present study is to provide the population specific sex discriminating osteometric standards to aid identification.A total of 483 crania (316 male and 167 females) with age range of 18-70 years of North Indian origin were studied using traditional osteometric methods. Twenty one traditional variables were measured. The p -value shows that all parameters were statistically significant and higher in males. The best parameters are bizygomatic breadth (BZBr) and mastoid bregma height (MBrHt) which were reflected by highest t values and highest classification accuracies i.e. 82.2 and 80.5% respectively. In stepwise analysis accuracy reached up to 84.75% with the selection of five variables named Bizygomatic Breadth (BZBr), Mastoid Bregma Height (MBrHt), Maximum Cranial Length (MaxCLt), Biauricular Breadth (BAUBr) and Maximum Cranial Breadth (MaxCBr). On the other hand, bizygomatic breadth (BZBr) alone provided a sex classification accuracy of 82.2 % in direct analysis.