Alternative workflows for identifying transnational missing persons.

Mass migration and migrant death at the U.S. southern border highlight the disconnectedness of the systems for transnational decedent identifications. Death investigation cases in Texas face delays and barriers at all stages of an investigation. Additionally, fragmentation of DNA databases exacerbate challenges in comparing genetic samples from unidentified human remains (UHR) and families of the missing. We sought to pilot alternative workflows for processing UHR and family reference samples (FRS) for the identification of probable migrant decedents. Primarily using Rapid DNA, but also accredited non-CODIS DNA laboratories, the piloted approaches were conducted in parallel to existing medicolegal workflows under the relevant case jurisdictional guidance. Our data show that Rapid DNA is a valid path for anthropology laboratories to support identification hypotheses and that accredited non-CODIS forensic and genetic laboratories also can support families to identify remains, especially when families reside outside of the United States.

Agreement and error rates associated with standardized data collection protocols for skeletal and dental data on 3D virtual subadult crania.

Observer error and agreement rates for craniometrics, odontometrics, and cranial and dental morphological traits have been inconsistently evaluated on three-dimensional cranial reconstructions and almost never assessed on subadult individuals. This study uses a computed tomography (CT) scan sample of 12 subadults aged between birth and 20 years from the Subadult Virtual Anthropology Database (SVAD) to evaluate intra- and inter-observer error and agreement rates associated to these four types of data on virtual crania. Forty-eight cranial landmarks, 33 standard inter-landmark distances (ILDs), 13 cranial macromorphoscopic traits, four permanent and four deciduous dental landmarks and measurements per tooth, and 21 permanent and 12 deciduous dental morphological traits were collected on each individual. Results matched or improved on published standards for dry bones, teeth, or dental casts. Technical Error of Measurement (TEM) associated with metric data ranged from 0.00 mm to 0.99 mm and relative TEM ranged from 0% to 5.76%. Cohen's kappa coefficient values for agreement on morphological traits scores were above K = 0.5 for 90% of the traits. Type III cranial landmarks showed higher error rates than Type I and II cranial landmarks. Agreement on dental morphology scores seemed influenced by observer experience and rater agreement improved when using di- or tri-chotomized grades. Skeletal maturity did not significantly affect error rates, meaning most craniofacial and dental metrics and morphological traits can be reliably obtained from virtual subadult crania.

Metric Methods for the Biological Profile in Forensic Anthropology: Sex, Ancestry, and Stature.

The biological profile, conducted by a forensic anthropologist, is necessary for severely decomposed or skeletonized remains. The biological profile consists of estimates of sex, age, ancestry, and stature. It is crucial to have a correct estimate of sex, as this designation will narrow down the search through missing persons reports by half (e.g., searching through NamUs). However, sex estimates can be population specific, necessitating accurate ancestry estimation. When estimates of age and stature are added, the search narrows further. If these estimates are incorrect, the unidentified human remains may never be identified. These biological profile components are estimated based on either metric or nonmetric methods (visual observation and recording of categorical data). While age is inherently nonmetric, stature is inherently metric. Estimates of sex and ancestry can take a metric or nonmetric approach. The purpose of this review article is to review metric methods in forensic anthropology (sex, ancestry, and stature), to provide general knowledge of why and how these metric methods work, and to highlight that estimates of sex, ancestry, and stature do not subscribe to a "one size fits all" model.

The Role of the Anthropologist in the Identification of Migrant Remains in the American Southwest.

This article focuses on the role of the forensic anthropologist in the identification of migrant remains in the American Southwest. These migrant cases present a unique set of circumstances that necessitate a regional approach to identification. The Pima County Office of the Medical Examiner (PCOME), located in Tucson, Arizona has developed best practices that facilitate high identification rates of migrant deaths. These best practices have provided a foundation for other agencies that are faced with similar issues; namely, developing specific protocols for migrant deaths, working with nongovernmental humanitarian organizations, and sharing information have maximized identification efforts. In 2012, Texas surpassed Arizona in the number of migrant deaths. The Forensic Anthropology Center at Texas State (FACTS) began identification efforts for migrant remains found in Brooks County, Texas in 2013. Informed by best practices from the PCOME, FACTS has made successful identifications. Descriptions of the processes at both the PCOME and FACTS are described in detail.

Ancestry assessment using random forest modeling.

A skeletal assessment of ancestry relies on morphoscopic traits and skeletal measurements. Using a sample of American Black (n = 38), American White (n = 39), and Southwest Hispanics (n = 72), the present study investigates whether these data provide similar biological information and combines both data types into a single classification using a random forest model (RFM). Our results indicate that both data types provide similar information concerning the relationships among population groups. Also, by combining both in an RFM, the correct allocation of ancestry for an unknown cranium increases. The distribution of cross-validated grouped cases correctly classified using discriminant analyses and RFMs ranges between 75.4% (discriminant function analysis, morphoscopic data only) and 89.6% (RFM). Unlike the traditional, experience-based approach using morphoscopic traits, the inclusion of both data types in a single analysis is a quantifiable approach accounting for more variation within and between groups, reducing misclassification rates, and capturing aspects of cranial shape, size, and morphology.