Morphometrics of the skull base for estimating sex among Koreans using 3D CT

Sex estimation is a core component of the biological profile, and the skull has long been regarded as a primary skeletal element for this purpose. However, morphological studies focusing on the skull base remain limited. This study aimed to derive discriminant functions using skull base measurements for sex estimation in modern Korean skeletal samples. Three-dimensional models of the skull base were generated from CT images of 198 decedents (103 males, 95 females), and 31 measurements were subjected to statistical analysis. Descriptive statistics revealed significant sexual dimorphism across all variables, with males exhibiting greater mean values than females in every measurement ( p < 0.05). Discriminant function equations were subsequently derived to facilitate sex classification. Univariate analyses yielded accuracies ranging from 61.6% to 83.8%, while a stepwise method incorporating five variables distributed across the overall skull base structure achieved a relatively high accuracy of 86.4%. To reflect forensic situations involving fragmentary remains, side-specific stepwise equations were developed; the right-side model achieved 83.3% accuracy, and the left-side model 78.8%. These findings support the utility of skull base measurements for sex estimation in a modern Korean population and highlight their applicability in forensic anthropology.