Evaluation of Purkait's Triangle Method for Determining Sexual Dimorphism


  • *Presented at the American Academy for Forensic Sciences 58th Annual Meeting, Seattle, WA, February 23, 2006.

Additional information and reprint requests:
Robert P. Brown, M.F.S.
22nd Military Police Battalion (CID)
PO Box 331009
Fort Lewis, WA 98433
E-mail: Robert.paul.brown@us.army.mil


ABSTRACT: The identification of sex from the skeleton is an important demographic assessment in medicolegal investigations. Rama Purkait developed a method for estimating sex using measurements from a triangle defined by three points on the proximal end of the femur using skeletal material from Bhopal, India. This method was tested with measurements on 200 Indo-European and African American adult femora from the Terry collection using discriminant function analysis to determine if Purkait's method was valuable for determining sex in Americans. A side-by-side analysis was conducted of Purkait's “triangle method” and the maximum diameter of the femoral head to determine their relative value in assessing sexual dimorphism. In the study sample a single variable from Purkait's method provided 85.5% prediction accuracy, similar to 87% for the head diameter. Combining threshold values for a single variable from Purkait's method and the femoral head diameter raised the predictability to greater than 90% for both sexes.