The skull is a reliable structure for determining the sex of an adult individual; it is generally resistant in adverse conditions, allowing it to be used for the analysis of sexual dimorphism. In the present study we analysed 10 non-metric characteristics of skulls of Brazilian adult individuals in order to: Determine the strength of association between sex and the morphological characteristics of the skull, the morphological characteristic(s) with greatest diagnostic influence for sex, and analyse whether the morphological characteristics of the skull predict sex. The study included 179 macerated skulls of Brazilian adults, (69 female, 110 male). The sex of all the skulls included was identified. The investigators were calibrated prior to analysis and all the evaluations were carried out under blinding. Pearson's Chi-squared test was used. The sensitivity and specificity were analysed and a ROC curve was constructed. Binary logistic regression was carried out. The SPSS v.22 software was used, with a significance threshold of 5 %. All the characteristics analysed presented statistically significant differences (p<0.05). The frontal profile, the superciliary arch and the glabella presented the greatest sensitivity, best balance between sensitivity and specificity and greatest area under curve. The regression model with the frontal profile, superciliary arch and mastoid process was significant [X2(2) = 115,728 p=0.000, R2 Negelkerke=0.657], and presented correct sex classification in 90 % of cases (Males: 87.4 %; Females: 83.1 %). In unknown individuals for whom the skull is present, non-metric analysis of the frontal profile, superciliary arch, mastoid process and glabella can be used as instruments for sex identification.
KEY WORDS: Sex determination; Morphological characteristics; Macerated skulls; Brazilians.