Introduction: The pelvic girdle consists of pelvic and sacral bones which is sexually dimorphic because of its contribution to the functional sex differences. Researchers have focused on deriving population-specific standards from multislice computed tomography (CT) scans through analyzes of inter-landmark distances to weight predictor variables and classify an unknown individual into one of several reference populations. Objective: This study aims to determine the relationship of morphometric of pelvic girdle with sex and ethnicity among the Malaysian population based on a total of 373 pelvic CT images collected at Kuala Lumpur Hospital. Method: The pelvic girdles were segmented from CT images through Mimics Research 17.0 software. Inter-landmark distances were measured with Microsoft 3D Builder. Results and Discussion: The relative technical error of measurements were in acceptable range at below 2% for both intra-observer and inter-observer error analyses. Results showed that the most useful sexual dimorphism parameters were acetabulum dimensions and the ilium height. The accuracy of demarcation points generated from the Receiver Operating Characteristics (ROC) curve for these parameters ranged from
83.5% to 89.1%. The success rates were 97.3% and 97.1% for respective male and female classification within the Malaysian population. On the other hand, the ilium transverse length, ilium breadth and pelvic inlet transverse diameter were the most useful ancestry differentiation parameters. These parameters showed highest in average values amongst the Chinese, followed by Malay and Indian segment of the Malaysian population. The comparative classification between Chinese and Indian achieved a higher success rate ranging from 64.5% to 67.2%. Conclusion: This population-specific study based on pelvic girdle amongst the Malaysian assist in enhancing the existing
database for Forensic Anthropologists and Forensic Radiologists to perform both sex and ancestry estimation on skeletal remains.

Keywords: Forensic Anthropology; Pelvic Girdle; Morphometric Analyzes; Sex Estimation; Ancestry Estimation; Malaysian Population.