The circumference interorbital index of the Isoko ethnic group in Nigeria

Aim: The aim of the study is to determine the circumference interorbital index amongst the Isoko ethnic group of Nigeria. Methods: This study was based on data collected from 600 Isoko subjects between 12–31 years of age in Delta State of Nigeria. Data was collected using a tape rule to measure the head circumference and a non-stretchable transparent centimeter ruler to measure the inner canthal distance. Circumference interorbital index was determined by measuring the head circumference and inner canthal distance. The head circumference was measured from the occipital prominence to the supraorbital ridge, while inner canthal distance was taken as the distance between the medial angles of the two eyes. Circumference Interorbital Index was calculated as Inner Canthal Distance (ICD)/ Head Circumference (HC) x 100. Mean and standard deviation for both sexes were calculated while t-test was employed as a statistical tool to search for significant gender differences. Results: The mean and standard deviation for Isoko male and female circumference interorbital indices were 6.62 and 6.58; 0.38 and 0.10 respectively. Conclusion: This study has provided a baseline data on circumference interorbital index of the Isoko ethnic group of Nigeria. The Isoko males displayed a higher circumference interorbital index than the females. Keywords: Anthropology, Craniofacial surgery, Forensic medicine, Isoko.