Morphometric study of the facial skeleton in Jordanians: A computed tomography scan-based study Ayman Mustafa a , Heba Abusamra a , Nadeem Kanaan b , Mohammad Alsalem c , Mohammed Allouh a, 1 , Heba Kalbouneh c, * a Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan b Jordanian Royal Medical Services, Jordan c Faculty of Medicine, The University of Jordan, Amman, 11942, Jordan A R T I C L E I N F O Article history: Received 19 November 2018 Received in revised form 11 March 2019 Accepted 14 March 2019 Available online 7 August 2019 Keywords: Sexual dimorphism Craniofacial parameters Discriminant function analysis Computed tomography Jordanians Age related changes A B S T R A C T Several studies have shown variability in osteometric measurements of the skull between populations. Therefore, each population should have specific standards to optimize the accuracy of identification. The aim of this study was to evaluate the sexual dimorphism in metric relations between anatomical points of the skull using CT scans in a Jordanian population by means of discriminant function analysis, to determine which continuous variables discriminate between sexes, and to examine the craniofacial changes according to age. 500 CT scans (240 males and 260 females) were used and a total of 11 craniofacial parameters were studied. The data were analyzed using distriminant function analysis. Sexual dimorphism was found mainly in the young adult group. Significant age related changes were noticed in minimum frontal breadth, orbital height and orbital index. In all subjects, the analysis of multivariate (dimorphic variables) and stepwise functions gave an accuracy of 58.8% and 57.0% respectively. Using stepwise analysis, the most dimorphic variables to estimate sex were maximum frontal breadth, bimaxillary breadth and orbital index. The multivariate analysis of all variables gave an accuracy of 58.8%. The percentages of correct sexing in Jordanian population were high using the single variable analysis in females only. In females, classification accuracies of 70.4% using bimaxillary breadth, 70.0% using the orbital index, and 68.1% using maximum frontal breadth were obtained. Additionally, discriminant analysis was conducted separately for each age group. Higher percentages of correct sexing were obtained only in young adults. The results of the discriminant function analysis did not appear to be significant. The results of discriminant function were insignificant in middle aged and elderly groups. Being female and young increases the percentages of correct sexing. Generally, low levels of accuracy of sexual dimorphism were obtained in our study, suggesting that population estimates of dimorphism are highly variable and the equations derived from the discriminant function analysis are not reliable in sex estimation in Jordanians © 2019 Published by Elsevier B.V. 1. Introduction The facial skeleton plays an important role in ancestry and sex estimation in the field of forensic anthropology. Currently, computers and modern technology such as X-ray computed tomography (CT) scanning, Magnetic Resonance Imaging (MRI), computer-based anthropometry, and biochemical analyses led to a huge advancement in anthropological studies that investigate the human skeletal features and their capacity as sex indicators [1,2]. Osteometric measurements made with radiological methods are more practical and applicable than many other identification methods [3]. The primary goal of the forensic anthropologist is to develop a biological profile, which includes age, sex, stature, and ancestry along with any marks that will make personal identification easier for the authorities [4]. Sexual dimorphism in the human skeleton exists due to differences of growth patterns both prior to and during adolescence, and the presence of bony ridges and projections as a result of the stronger muscular attachments seen * Corresponding author at: Department of Anatomy and Histology, Faculty of Medicine, University of Jordan, Amman 11942 Jordan. E-mail addresses: agmustafa@just.edu.jo (A. Mustafa), abusamraheba2015@yahoo.com (H. Abusamra), nadeemkanaan@yahoo.com (N. Kanaan), m_alsalem@ju.edu.jo (M. Alsalem), m_allouh@just.edu.jo (M. Allouh), heba.kalbouneh@ju.edu.jo (H. Kalbouneh). 1 1Present address: College of Medicine & Health Sciences, United Arab Emirates University, Al Ain - 17666, UAE. http://dx.doi.org/10.1016/j.forsciint.2019.109916 0379-0738/© 2019 Published by Elsevier B.V. Forensic Science International 302 (2019) 109916 Contents lists available at ScienceDirect Forensic Science International journal homepage: www.elsevier.com/locat e/f orsciint