Evaluation of effectiveness of cranial morphological characteristics for sex estimation in a Brazilian sample

Abstract

Forensic physical anthropometry allows the determination of animal species and estimates sex, ancestry, age and height. Aim: To analyze the effectiveness of a cranioscopic/ morphological evaluation for sex estimation with a sample of the Brazilian mixed-race population by conducting a qualitative visual assessment without prior knowledge of sex. Methods: This is a blind cross-sectional study that evaluated 30 cranial characteristics of 192 skulls with mandible, 108 male and 84 female individuals, aged 22 to 97 years, from the Osteological and Tomographic Biobank. The qualitative characteristics were classified and compared to the actual sex information of the Biobank database. The statistical analysis was used to calculate de Cohen’s kappa coefficient, total percentage of agreement, sensitivity and specificity of visual sex classification. Results: Of the 30 cranial variables analyzed, 15 presented moderate degree of agreement, achieving value of Kappa test between 0.41–0.60: Glabella (Gl), Angle and lines (At), Mental eminence (Em), Mandible size (Tm), Cranial base (Bc), Mouth depth (Pb), Nasal aperture (Anl), Supraorbital region (Rs), Orbits (Orb), Mastoid processes (Pm), Alveolar arches (Aa), Zygomatic arch (Az), Orbital edge (Bo), Supraorbital protuberances (Pts), and Supramastoid crests and rugosity (Crsm). The Facial physiognomy (Ff) presented substantial reliability (0.61-0.80) with 89.8% sensitivity for male sex and 70.2% specificity. Conclusions: Cranial morphological characteristics present sexual dimorphism; however, in this study only 15 variables showed moderate degree of agreement and can be used in sex estimation. Only one variable (Ff) 81.2% total agreement with substantial reliability. Quantitative methods can be associated for safe sex estimation.

Keywords

• Sex characteristics
• Forensic anthropology
• Skull
• Mandible