Is “Latin American” population-specific? Testing sex discriminant functions from the Mexican tibia on a Chilean sample

Latin American populations are traditionally reported as one ancestral group in the forensic anthropology literature. However, this study illustrates the need for population-specific methodologies for ancestral groups that are considered Latin American. This project evaluated the accuracy of the sex estimation discriminant function created from the tibia of a Mexican population, when applied to a Chilean population. The maximum distal epiphyseal breadth (MDEB) and the anterior-posterior diameter at the nutrient foramen (APDNF) were measured on 203 tibiae (108 males and 95 females) from the Subactual Skeletal Collection at the University of Chile. The individuals ranged in age from 20 to 96 years old. When the Mexican discriminant function was applied to the Chilean population, accuracy rates ranged from 76.0% (males) to 85.0% (females). Mean tibial size comparisons were made to a Mexican, Croatian, White South African, archaeological Hispanic, and North Indian population and showed some significant differences between the variables measured. Population-specific discriminant functions were created for the Chilean population with overall sex classification accuracy rates of 71.4% (MDEB only) to 89.2% (MDEB and APDNF). This study illustrates the need for population-specific and temporally-specific discriminant functions for estimation of sex from the tibia.