An examination of musculoskeletal markers in modern populations for forensic analysis and identification purposes

This project will investigate the utility of musculoskeletal markers (i.e., entheseal changes) to estimate occupation, physical level, or socio-economic status in unidentified skeletal remains for the purposes of medicolegal casework. This project has relevance to the forensic anthropological community because it can add an individualizing biosocial component to the standard bioprofile usually generated. Musculoskeletal markers have been identified as predictors of occupation and age in archaeological populations and have been shown to correlate with childhood socio-economic status in a modern population. However, their validity in forensic casework remains unclear, and although bioarchaeological studies have seen success in estimating lifestyle indicators and activity level, few attempts have been made to interpret these changes in a modern forensic context to assist positive identification efforts. Publications show inconsistent methodology for observing entheseal changes, including different scoring systems and statistical tests and deficient photographic documentation of the variation seen in entheseal changes, making scoring, replication, and teaching of these methods difficult. These limitations result in the generation of non-comparable data, little standardization, and minor impact for entheseal studies in general, which this research will address via the development of improved statistical analyses and training models. To test whether entheseal changes can identify biocultural patterns in modern populations, this project will examine entheseal changes in the upper limbs of 1,000 modern Americans curated in three documented skeletal collections. Sample composition will include both sexes, all self-reported socio-economic statuses and occupations, a minimum age of 21, and the presence of upper limbs. This project will utilize the Coimbra Method (Henderson et al., 2013, 2016) to score entheseal changes, and the datasets will be analyzed using a latent class analysis model, with entheseal changes serving as response variables and the self-reported information as covariates. The model will assess how to sort the population based on an unmeasured latent variable that highlights trends throughout the data that cannot be measured, so that individuals can be categorized based on entheseal changes (observations) by different types of biocultural affiliations (latent classes). This process will address previous limitations and allow for more rigorous statistical analyses of the data to assess whether entheseal changes of the upper limb are useful individualizing components. The results will be disseminated through manuscripts submitted to peer-reviewed journals. Photographs and 3D reconstructions will be provided to researchers through online open source venues, and workshops will be offered by the Forensic Anthropology Center at Texas State University. Note: This project contains a research and/or development component, as defined in applicable law, and complies with Part 200 Uniform Requirements - 2 CFR 200.210(a)(14). CA/NCF