Variability of the Pattern of Aging on the Human Skeleton: Evidence from Bone Indicators and Implications on Age at Death Estimation

Abstract

Age at death assessment of adult skeletons is one of the most difficult problems in forensic and physical anthropology. Two fundamental sources of error are described: the complex variability in the process of skeletal aging and methodological bias. Taking into account these limits, we developed a new scoring system for the auricular surface of the ilium and the pubic symphysis. In order to address a large variability, we examine reference samples from Europe, North America, Africa, and Asia. Data were processed using Bayesian prediction in order to classify specimens in age range categories. Results show that combining indicators do not perform better than the auricular surface used as a single indicator. Morphological changes with aging are variable between Asian, African, and European populations, confirming the necessity to use population-specific standards. Bayesian prediction produces reliable classification and is applicable for subjects over 50 years old, a real methodological improvement.

Estimation of age at death from the pubic symphysis and the auricular surface of the ilium using a smoothing procedure

“…In the present work, a few results contradict those obtained by Schmitt et al [27]. Notice that we are using the same samples, but a different statistical methodology.…”

“…This idea has been widely explored as in [40][41][42][43][44][45][46][47][48][49], for example. The scoring system introduced by Schmitt et al [27] does show this proximity feature, thus giving justification to use of smoothing methods.…”

“…Pubic symphysis and auricular surface of the ilium have been largely exploited to create methods, but these were based on observations of a single population [22][23][24][25][26]. One of authors has tested her method based on a worldwide learning sample [27] using a Bayesian prediction approach in order to classify individuals in age range categories. The results show that combination of the pubic symphysis and the auricular surface of the ilium do not perform better than the auricular surface used as a single indicator.…”

“…The present work proposes to use the samples and the scoring system suggested by Schmitt [27][28][29] using another statistical treatment in order to improve age at death assessment.…”

“…These samples and the scoring system of the two indicators were used by Schmitt et al (2002), applying the methodology proposed by Lucy et al (1996). In the present work, the same data was processed using a modification of the empirical method proposed by Lucy et al (2002).…”