ACCURACY AND RELIABILITY IN SEX DETERMINATION USING THE OS COXA: A COMPARISON OF METRIC VS. PHENICE METHOD

Determination of biological sex is one of the most important determinations to be made from undocumented human remains and is an essential first step in the development of the biological profile in forensics and bioarchaeology. The chances of attaining high levels of accuracy & reliability regarding sex identification are related to the skeletal components analyzed and the ability of techniques utilized to analyze shape and size differences among the sexes. Current opinion regards the ossa coxae or hip bone as the most reliable sex indicator because it is the most dimorphic bone, particularly in adult individuals. The aim of this study was to compare the Phenice method & metric measurements of the os coxa to determine the most accurate and reliable method to determine sex. Metric measurements used were the os coxa height, pubis length, ischium length, iliac breadth, and the greater sciatic notch width. 101 individuals of known sex from the Maxwell Museum collection were used in this study. Sex was correctly estimated in 93.1 % of all individuals for both methods with a higher accuracy estimated in females than males. The Phenice method incorrectly estimated 7 males and no females. The metric method incorrectly assessed 2 females and 5 males. An intra-observer error test completed on a random sample proved the Phenice method to be more reliable and accurate on a repeatable basis. Previous experience in human osteological analysis was shown to have no effect on accuracy in this test using the Phenice method, confirming Phenice’s assertion that the technique does not require extensive experience to yield accurate results.