Validation of Falys and Prangle’s (2015) Approach to Estimating Age in Mature Adults: A Scottish Population Study

Age estimation is a fundamental piece of information both for biological and forensic anthropology. Methods for adult age estimation primarily focus on the degenerative changes of different skeletal elements. As individuals age, the correlation between biomarkers and age weakens, making the aging process of older adults more difficult. Thus, methods usually consider individuals over 50 years as ‘mature or old adult’, effectively rendering part of the population sample “invisible” within the archaeological record and too wide for forensic contexts.
In an effort to further explore age estimation in mature adults, Falys and Prangle (2015) proposed a macroscopic method based on observing the degenerative changes on the sternal end of the clavicle. The present study aims to validate the proposed method and assess its applicability to a contemporary elderly Scottish population (N=47). Three primary degenerative traits were assessed: surface topography (TOP), porosity (POR), and osteophyte formation (OST). Individual and composite scores were recorded for every clavicle, intra-observer error was estimated using kappa statistics, and accuracy and bias were assessed using regression equations of the original study. The composite score method demonstrated an accuracy of 62% within two standard deviations, and the regression formulae for known and unknown sex provided a slightly higher accuracy rate of 62% and 64%, respectively. The results of this study suggest that the sternal end of the clavicle has the potential to aid age estimates in mature adults but indicate the need for further research on the morphological features of the clavicle and their correlation with age.