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Sex estimation is perhaps the most important component of the biological profile. Our sex estimates aid in decedent identification by helping to narrow the missing persons list, and set the basis for many of the remaining biological profile estimates (age, ancestry, stature), which factor in sexual differences. A review of the current research and general literature reveals the use of a wide variety of methodological approaches to sex estimation, which are far from standardized. The goals of this work are (1) reviewing the current state of sex estimation, based on practitioner preferences, case studies, research publications, and proposed standards; (2) presenting and discussing opposing viewpoints regarding issues such as the lack of agreement on terminology standards; whether sex should be estimated at all in subadults; different analytical and data collection approaches; and whether it is appropriate to directly apply sex-specific methods if sex has been positively established, or if keeping a blind approach is still necessary in that case, in order to prevent observer biases; (3) discussing current challenges and future applications; and (4) summarizing the review with a set of recommendations and suggestions for future practice. [ABSTRACT FROM AUTHOR]

Letter to the Editor - Moving beyond a lost cause: Forensic anthropology and ancestry estimates in the United States. Bethard and DiGangi opened a dialogue on the application of ancestry estimation as part of the biological profile in forensic anthropology [1]. Anthropologists accept the social construction of race and are acutely aware of its harmful impact in American society, particularly with respect to the historic use of anthropology to promote scientific racism. Research has assessed accuracy rates of ancestry estimations by forensic anthropologists and reported correct ancestry estimates at 90.9% [13]. [Extracted from the article]

The optimized summed scored attributes (OSSA) method was first developed for cranial ancestry estimation (Hefner & Ousley 2014). Tallman and Go (2018) adapted this method for sex estimation with the five skull traits described by Buikstra and Ubelaker (1994) and Walker (2008). Using an Asian sample, Tallman and Go (2018) achieved moderate accuracy rates (83.7% calibration; 81.9% validation) but also high sex bias (29.1% calibration; 34.5% validation), possibly due to lower levels of sexual dimorphism in Asian populations. To further explore this novel approach to sex estimation, the OSSA method was applied to a U.S. Black/African ancestry and White/European ancestry calibration sample (N = 700). Accuracy rates were 77.4% in Black individuals and 77.2% in White individuals. Despite generally higher levels of sexual dimorphism in these groups, a high sex bias still occurred (15.4% Black individuals; -20.5% White individuals) using OSSA. The method was tested in a separate validation sample (N = 200) with accuracy of 78.0% in Black individuals (8.0% sex bias) and 70.0% in White individuals (-56.0% sex bias). When these same traits were tested with Walker's (2008) logistic regression and in the MorphoPASSE Program (Klales 2018) using random forest modeling, accuracy rates varied, with OSSA (77.3% correct), performing slightly better than Walker's (2008) method (75.6% correct) but worse than MorphoPASSE (85.3% correct). The higher accuracy and lower sex bias in MorphoPASSE suggests that the Walker (2008) traits can be used to accurately estimate sex with statistical approaches more appropriate and robust than OSSA. [ABSTRACT FROM AUTHOR]

Morphological skull and pubic traits are routinely used in forensic anthropological casework for sex estimation, with the Walker (2008) and Klales et al. (2012) methods commonly employed. This research aims to present a comprehensive evaluation of reliability in skull and pubic trait scoring and the implications of observer scoring variation on sex estimation accuracy. Results from previous studies are summarized and compiled into tables for comparisons. Data from this study are composed of a large compilation of Walker (2008) and Kales et al. (2012) trait scores (skull n = 392, pubic n = 443) contributed by seven researchers of varying levels of expertise. Intra- and interobserver analyses were performed on the trait scores, and variations in correct sex classifications were assessed among observers, with particular emphasis on the effects of observer experience. Statistical results indicate that the traits utilized in Walker (2008) and Klales et al. (2012) can be reliably scored except for the mental eminence, which has shown considerable variation among studies and individuals. Resultant sex estimations improved with experience level, with the highest accuracy rates for both methods among experts. Although novice observers had good agreement in trait scores with more experienced observers, minor scoring differences negatively impacted classification accuracy, particularly in the Klales et al. (2012) method with more than a 15% drop in accuracy. The results highlight the importance of experience and exposure to human variation and training in these sex estimation methods and also suggests data from expert practitioners can be combined into larger databases. [ABSTRACT FROM AUTHOR]

Abstract: Langley et al. (2017) developed a sex estimation decision tree utilizing two traditional cranial traits (glabella and mastoid) and a new trait: zygomatic extension. This study aimed to test the reliability of their zygomatic extension scoring method and validate their sex estimation method. Ordinal score data were collected from 281 male and female U.S. White and Black individuals. The five traditional cranial traits were collected from physical specimens, while zygomatic extension was scored from 3D cranial models. Intra‐ and interobserver analyses carried out on a subsample of 30 individuals indicate good agreement between zygomatic scores. The decision tree correctly sexed 71.5% of the sample, but a strong sex bias (94.2% correct for females, 49.3% correct for males) severely limits the utility of this method. The Walker (2008) and Stevenson et al. (2009) methods produced higher accuracy rates (80.8% and 82.6%, respectively), although these methods also produced sex and ancestry biases. [ABSTRACT FROM AUTHOR]

ABSTRACT Human molars exhibit varying shapes when viewed from the occlusal surface. Available methods for quantifying molar occlusal shape have historically been confined to qualitative descriptions. The present study utilized geometric morphometric analyses to capture molar shape as defined through relative cusp locations. Cusp apices of maxillary and mandibular first and second molars were digitized from 190 American Blacks and Whites to estimate biological affinity through the shape of relative cusp locations. The coordinate data were subjected to a Generalized Procrustes Analysis to generate Procrustes coordinates and calculate centroid sizes. Procrustes coordinates were then subjected to a principal component analysis to examine the direction and magnitude of shape change inherent in the sample. Centroid size and major shape component group means were compared with t-tests. Interlandmark distances were then calculated from the raw coordinate information and also subjected to a principal components analysis. Procrustes coordinates and the principal components derived from them with and without centroid size, along with the interlandmark distances and the principal components derived from them, were each subjected to a discriminant function analysis to examine which methods yielded the highest correct classification between population groups. Total correct classifications ranged from 62.7% to 87.9% depending on the variables forward stepwise selected for each analysis. Using a combination of the second maxillary molar and first mandibular molar yielded the most optimistic results and corroborates theoretical models of molar development. Am J Phys Anthropol 153:269-279, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]