Validation of walker's non-metric sex estimation method using 3D glabella images in Koreans: A metric approach

Computed tomography (CT) is excellent for examining the skull and providing a contiguous series of cross-sections and three-dimensional information. We aimed to develop a forensic anthropological method for determining sex in Koreans, involving a metric analysis of the glabellar region volume derived from three-dimensional CT images of the skull. A total of 661 CT images of Korean skulls were obtained. Of these, 100 CT images were randomly selected for non-metric sex estimation using the Walker method, and the remaining 561 CT images were used to derive a regression equation for sex estimation in Koreans using the metric method. To verify the validity of the derived equation, we analyzed 100 CT images previously selected for non-metric sex estimation using the metric method. The glabellar region volume was greater in males than in females. Moreover, measuring the glabellar region volume using the metric method increased sex estimation accuracy by 5 % compared to the non-metric method. We elucidated a new measurement range and method for measuring the glabellar region volume. The sex matching rate of the metric method was similar (81 %) to that reported in a previous study that used a non-metric method. In summary, we quantitatively discriminated sex using three-dimensional measurements of the glabellar region and demonstrated that the non-metric sex estimation method based on skull data of the non-Korean population is not suitable for estimating sex using the glabella in Koreans. The metric method proposed in this study will increase the accuracy and reliability of sex estimation in Koreans.