Best practice for osteological sexing in forensics and bioarchaeology: The utility of combining metric and morphological traits from different anatomical regions

Abstract

This paper aims to systematically investigate the value of combining traits from different anatomical regions in osteological sexing by contrasting the utility of single traits and established scores with those of ensembles of traits from single or multiple anatomical regions, allowing metric and morphological traits to be combined. The utility was defined as the fraction of the population for whom we could reach a posterior probability above 95% of being male or female. A total of 675 adult individuals from the sixth to eighth century AD cemetery of Mannheim Bösfeld, Germany, were assessed, and 27 postcranial metric traits and 41 morphological traits from the pelvis, mandible, and cranium were used. In addition, 13 metric and 3 morphological scores were considered. Linear discriminant analysis (LDA) was used to construct rules and cross validation to determine accuracy and utility. These parameters were determined for single traits and scores, trait groups defined by anatomical regions and/or previously considered in the literature, and ensembles of traits defined by selecting several promising traits from different anatomical regions. Accuracy of single traits ranged from 0.76 to 0.94, with scores even reaching 0.97, but utility remained around 0.2-0.4 for metric traits and up to 0.6 for morphological traits. Only scores and ensembles combining traits from different anatomical regions reached a utility above 0.7; that is, sex could be estimated in more than 70% of the individuals with a posterior probability above 95%. When selecting a limited number of traits for systematic sexing in a human skeletal series, it is advisable to select traits from different anatomical regions to obtain a reasonably reliable result in as many individuals as possible. Large scale investigations covering all relevant anatomical regions and involving a wide range of populations are required for more precise recommendations.

Age‐at‐death estimation in archaeological samples: Differences in population means resulting from different aging methods can be predicted from the mean ages of method‐specific reference samples

“…All 675 adult individuals from the early medieval cemetery of Mannheim-Seckenheim ("Hermsheimer Bösfeld"), Germany, were analyzed in this study (see also Navitainuck et al, 2021). Classification as an adult individual was based on complete epiphyseal closure (especially the spheno-basilar junction).…”

Sex determination of medieval skeletal remains

“…Alongside age determination, sex determination is an important element within the forensic and bioarchaeological analysis of human archaeological skeletal remains (Tekeli et al, 2020;Navitainuck et al, 2021). According to The Cambrige Dictionary of Human Biology and Evolution by Mai et al (2005), sex represents "biological category based upon reproductive attributes and roles in sexually reproducing species".…”

“…The most commonly used bones with traits reliable for sex estimation are postcranial and pelvic bones (Spradley, 2016). A study conducted by Navitainuck et al (2021) showed that morphological traits of the cranium and pelvis are at an advantage compared with metric traits of pelvis and scapula, due to their higher utility in the purpose of sex estimation. The other research conducted by Inskip et al (2018), focused on os coxae and skull traits, revealed their high sex estimate accuracy, with an accent on os coxae or pelvic traits.…”