1Department of Anthropology, The Ohio State University, 2Central Identification Laboratory, Joint POW/MIA Accounting Command
Friday All day, Clinch Concourse
There is a need in forensic anthropology and bioarchaeology for accurate and easily replicable age estimation methods that produce reliable and timely results. The goals of this study were to quantify the amount of variation explained by age in two variables: proportion of intact osteons comprising osteon population density (OPD) and total number of osteon fragments, and to explore the extent to which these variables may improve existing age estimation methods. The anterior, posterior, medial, and lateral regions of 200 femoral cross-sections from known-age individuals from the Ericksen sample were examined histologically (100x magnification) using a three-columned checkerboard pattern read from the periosteal border to the endosteal border. Univariate simple linear regression analysis was used to assess the relationships between these two variables and known age. As the aim of this study was to predict an individual’s age when a particular value of a variable is observed, inverse prediction was employed. The resulting r2-values for the proportion of intact osteons comprising OPD for each region and for the total cross section fell below 0.50, indicating that less than 50% of the variation observed is explained by age. Conversely, the r2-values for osteon fragments were greater than 0.50, indicating that more than 50% of the variation observed is explained by age. These results suggest that the proportion of intact osteons comprising OPD is not likely to increase the reliability of histological age estimation methods and that more accurate age estimations can be achieved using the total number of osteon fragments.