ABSTRACT
Objective: To evaluate the accuracy of sexual dimorphism in the cranium and mandible of Thais using Krogman’s cranioscopy and the modified Krogman’s cranioscopy traits by grading and measurement. Methods: Data were from 101 dry adult skulls (66 males and 35 females) residing in central Thailand. Results: Sex determination using Krogman’s cranioscopy by an inexperienced person had a very high accuracy of 95.5% for males, 82.9% for females respectively and 91.1% overall. According to modified Krogman’s cranioscopy traits by grading, males had larger supraorbital tours, a rougher glabella region and more external occipital protuberance than females. Regarding modified Krogman’s cranioscopy trait by measurement, males had a wider base and a higher mastoid process, with longer and wider occipital condyles than females. Both later methods were also useful in the sexing of fragmented skulls. Conclusion: The cranioscopy study based on 14 traits according to Krogman’s cranioscopy is the best method for sex determination of individual unknown skulls. The modified Krogman’s cranioscopy trait by grading and by measurement is simplified and can very well predict the sexing of fragmented skulls.
ABSTRACT
Objective: To evaluate sexual dimorphism in the cranium and mandible of Thais by using Jorgensenûs craniometry and to develop a statistical model to determine sex from craniometrical measurements and indices. Methods: One hundred and one Thai skulls (66 males and 35 females) which ranged in age from 18 to 86 years were studied. Results: According to craniometry, the skull of a male is larger and higher than that of a female. Considering each individual measurement, although 26 of 30 measurements and 5 of 14 indices showed a statistically significant difference between males and females, they had some overlaps. To predict gender more accurately, a multiple logistic regression model based on 4 skull measurements (mm) i.e., nasion-basion length (M5), maximum breadth of the cranium (M8), facial length (M40), and bizygomatic breadth of the face (M45) was developed as follows: In (odds) = Z = -52.5312 + 0.27 M5 - 0.1867 M8 + 0.1268 M40 + 0.319 M45 The probability of being males (P) is then ez/(1+ez). Using a cut off point for P of 0.5, this logistic model could correctly predict 82.9% (95% CI: 66.4%, 93.4%) of females and 92.1% (95% CI: 82.4%, 97.4%) of males respectively with the overall accuracy of 88.8% (95% CI: 80.8%, 94.3%). Conclusion: Jorgensenûs craniometry of the cranium and mandible can be used to determine gender among Thais via a multiple logistic regression model on M5, M8, M40 and M45.