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Confidence intervals for age estimation. The 95% confidence intervals (95%CI) for age estimation according to the linear regression model are displayed for each score and each sex category. Confidence intervals were estimated using bootstrapping
Source publication
Age estimation is a key factor for identification procedure in forensic context. Based on anthropological findings, degenerative changes of the sternal extremity of the 4th rib are currently used for age estimation. These have been adapted to post-mortem computed tomography (PMCT). The aim of this study was to validate a post-mortem computed tomogr...
Citations
... Spearman's rank correlation coefficient was used to determine whether there were significant correlations between the real ages at death and the estimated ages at death obtained using the Suchey-Brooks method. We also used this approach to evaluate the relationship between age at death and score in the same way as Richard et al. [16]. All of these observations were made for both views (LFOV and SFOV) to be able to compare them. ...
... Thus, we recommend that other age at death estimation studies should be tested, as did Richard et al. [16] when tracking age-related morphological changes in the fourth rib using the method of Isçan and colleagues [34]. Savall et al. suggested the creation of a digital reference sample in the forensic context, which makes more sense when comparing an individual in a 3D reconstruction [7]. ...
... Over recent years, the use of virtual anthropology techniques [39], in particular the technique known as virtual morphology [40], has spread. Clinical images from computed tomography (CT) or magnetic resonance imaging (MRI) have provided an excellent source of complementary data for non-invasive studies in modern populations [11], which have been successfully used to estimate age [41], specifically applying the Iscan method [42][43][44][45]. In addition, other technologies such as surface scanners have also been widely used to obtain high-resolution 3D models. ...
... Other works using CT scans obtained very similar figures to those obtained by Dedouit et al. [42] and ours. Among them, two Australian studies with values of κ = 0.854 [43] and κ = 0.76 [44], and a recent study carried out in France (κ = 0.85) [45] are of particular importance. In our study, we used a surface scanner, so despite the results not being fully generalizable, we can confidently state that they were in line with other studies as regard the use of 3D images. ...
... Unlike our results, Dedouit et al. [42] showed a similar or slightly higher degree of agreement in CT reconstructions than in dry bone. Other research using CT scans with living [44,58] and post-mortem subjects [45,54] also shows almost perfect agreement. Although our numbers were slightly lower, they can still be considered substantial (κ = 0.727), and we can confirm the findings by Villa et al. [48] on pubic bone and the auricular surface regarding the superiority of direct observation of the bone (κ = 0.30-0.77) ...
When investigating a death, post-mortem identification provides with results of great legal and humanitarian significance. The effectiveness of the methods used to estimate age depends on the reference population, considering variables such as sex and ancestry. The aim of this study was to validate the Iscan method to estimate age in a Spanish forensic population, comparing the estimates obtained in dry bones and 3D reconstructions created with a surface scanner. We carried out a cross-sectional study on 109 autopsied corpses (67% male), scanning the sternal end of the right fourth rib in a 3D mesh, using an EinScan-Pro® surface scanner (precision: 0.05 mm). Two observers estimated the phases in dry bones and 3D images according to the Iscan method and to the sex of the subject. The mean age was 57.73 years (SD = 19.12 years;18–93 years). The intra-observer agreement was almost perfect in bones (κ = 0.877–0.960) and 3D images (κ = 0.954), while the inter-observer agreement was almost perfect in bones (κ = 0.813) and substantial in 3D images (κ = 0.727). The correlation with the Iscan phases was very strong in bones (Rho = 0.794–0.820; p < 0.001) and strong in 3D images (Rho = 0.690–0.691; p < 0.001). Both sex-adjusted linear regression models were significant (dry bones: R² = 0.65; SEE = ± 11.264 years; 3D images: R² = 0.50; SEE = ± 13.537 years) from phase 4 onwards. An overestimation of age was observed in the first phases, and an underestimation in the later ones. Virtual analysis using a surface scanner in the fourth rib is a valid means of estimating age. However, the error values and confidence intervals were considerable, so the joint use of different methods and anatomical sites is recommended.
... The method most commonly used to associate morphological sternal rib end changes with biological age is that proposed by İşcan et al. (1984). Validation studies of this method have produced mixed results (Muñoz et al., 2018;Richard et al., 2022), and attempts have been made to refine it (Merritt, 2018b;Yoder et al., 2001) but their use has not been generalized in the literature. ...
Age-at-death, sex, and stature estimation from adult human skeletal remains lie at the core of bioarchaeolog-ical and forensic anthropological research. Several methods have been proposed for such estimations, with almost all of them being developed using modern documented skeletal collections. Therefore, unavoidably bioarchaeology largely adopts relevant methodologies from forensic anthropology. Applying these osteolog-ical age-at-death, sex, and stature estimation methods to archaeological skeletal remains relies on the inherently flawed assumption that biological processes are homogenous across time and space. This paper offers a brief review of some of the key methods bioarchaeology has adopted from forensic anthropology, stressing the limitations of blindly using methods developed based on contemporary assemblages on archaeological ones, but also on systematic efforts that have been made to address these limitations.
