Forensic Science International: Reports最新文献

Sexual assault is a chronic problem around the globe, and those who choose to report a sexual assault are faced with further traumatic experiences within the justice system. There are many points at which these experiences could be improved, to support the complainant through the process. This qualitative evidence synthesis focused on the forensic medical examination (FME) as a point for potential improvement. Literature that focused on patient and medical practitioner experiences of the FME were reviewed and analyzed for themes that might suggest ways in which the FME process could be made better from the patient’s perspective. Three themes were identified. One related to the tension between the dual aims of the FME, of providing therapeutic healthcare and evidence for police investigation and prosecution. For the patients, these dual aims needed to be seen as healthcare first and forensic evidence as a secondary decision. The second theme was around the experience of the FME as traumatic, and the need for specialist training for practitioners was affirmed. Although women practitioners were preferred, the behavior and skills of the practitioner was more important. Their practice needed to be trauma-informed and patient-centered. The third theme was around optimizing the FME in terms of collecting the evidence that would have the most impact on the subsequent police and judicial processes, depending on the situation. For this optimization, further research is needed to trace the linkages between evidence and justice outcomes.

A new calculation module within the PopStats module of the CODIS software package, based on the underlying mathematics presented in the MixKin software package, has been developed for assigning the Likelihood Ratio (LR) of DNA mixture profiles. This module uses a semi-continuous model that allows for population structure and allelic drop-out and drop-in but does not require allelic peak heights or other laboratory-specific parameters. This new implementation (named SC Mixture), like MixKin, does not specify or estimate a probability of drop-out. Instead, each contributor to a mixture has an independent drop-out rate, and the probability of the mixture profile for a specified proposition concerning the contributors is integrated over the range of possible drop-out rates. The allelic drop-in rate and the population structure parameter, theta, used by the software are specified by the user. The user can examine up to five contributors to a mixture, however, conditioning on assumed contributors and limiting the number of unknowns in both numerator and denominator hypotheses greatly improves performance. We report results from an extensive validation study performed for ten mixtures with each of one (single source), two, three, four, or five contributors, with four combinations of drop-in rate and a population structure parameter. Each mixture was run as a complete profile or with the random removal of alleles to simulate drop-out. All 1620 combinations were evaluated with PopStats, MixKin, and LRmix and considerable consistency was found among the results with all three packages.

Purpose

Age estimation plays a pivotal role in the forensics sciences, medico-legal and clinical dentistry fields. The Willems method has gained significant recognition over the past two decades; however, the accuracy of it varies between population groups and across different regions within a country. Consequently, the present study aimed to investigate the reliability of the Willems scoring systems to a select South African population.

Methods

A cross-sectional assessment of 600 digital panoramic radiographs of patients (n = 600: 300 South African Black and 300 South African Indian) between 5.00 and 19.99 years old were employed retrospectively. The dental age was calculated utilizing the Willems et al. (2001) and Willems et al. (2018) scoring systems. Discrepancies between the chronological and dental ages were statistically analyzed.

Results

An over-estimation of dental age utilizing the Willems et al. (2001) and Willems et al. (2018) scoring systems was recorded in the selected sample of KwaZulu-Natal. A significant statistical difference between the chronological age and estimated dental age was recorded for both methodologies. Therefore, this study attempted to increase the accuracy of the Willems scoring system in a selected sample of South Africa by generating the following two novel population-specific age predictive models (excluding and including third molars).

Conclusion

The population-specific model performed better than the Willems scoring systems for the select sample, with the lowest mean errors and an insignificant statistical discrepancy noted between the chronological and dental ages (p-value >0.05). Therefore, these population-specific models may be used for forensic and medico-legal cases within this region.

Dentition plays a crucial role in the fields of forensic science, forensic odontology and anthropology for age and sex estimation. The aim of this study was to determine the degree of sexual dimorphism and age prediction capabilities of permanent dentition using morphometric analysis. Six hundred digital panoramic radiographs (n = 600), belonging to 300 South African Black and 300 South African Indian, aged between 5.00 and 19.99 years were retrospectively examined using a cross-sectional design. The Pearson Correlation Coefficient tests were conducted to determine if a correlation exist between age, sex and each morphometric parameter. “Stepwise Regression Analysis” and “supervised machine learning classification” with a recursive feature elimination and logistic regression were then utilized to parsimoniously prune the morphometric parameters to determine the best models for age and sex estimation, respectively. Males generally displayed larger tooth dimensions than females, with the South African Black population group having larger tooth dimensions than the South African Indian population group. The morphometric parameters of the dentitions showed little sexual dimorphism, with weak correlations less than 0.1, in this study. However, strong correlations between age and the tooth length of the second and third maxillary and mandibular molars (R² > 0.89) were recorded for the select South African Black and Indian population groups. In conclusion, the sex estimation formulae generated in this study had low performance accuracies for both population groups. However, the age estimation formulae developed from “Stepwise Regression Analysis” in this study were reliable predictors of age, with the tooth and root lengths displaying the best models for age estimation for the South African Black and Indian sample (R² > 0.9).

Age-at-death estimation is an essential step in both bioarchaeological and forensic studies when human remains are found, as this can also contribute to the identification of the individual. It is critical that age-at-death methods be tested verified in various populations, to obtain the most accurate estimation, making research into new age-at-death methods also imperative. Since osteophyte formation on the vertebral column increases with age, this can be used as a possible method of age-at-death estimation. Snodgrass (2004), Watanabe and Terazawa (2006) and Praneatpolgrang et al. (2019) have tested this method before and have provided promising results. We test the efficacy of Snodgrass (2004), Watanabe and Terazawa (2006), and Praneatpolgrang et al. (2019) on a 19th-century archivally recorded Dutch population. A total of 88 individuals, 40 males, and 48 females were scored for the degree of osteophyte formation on the vertebral column. In addition to testing the three methods above, population-specific regression equations were developed and tested. Accuracy percentages for estimating the age-at-death based on the mean osteophyte score of the entire vertebral column were obtained for all three methods (73.86%, 76.14%, and 72.73%, respectively). In this study, a general pattern of osteophyte formation could be established, which is useful for estimating the age at death. We therefore recommend that this method can be used, cautiously as a means of age-at-death estimation.

Allele frequencies of 15 autosomal STR loci were established from 540 unrelated Myanmarese individuals using the Thailand Office of Police Forensic Science database. The DNA profiles were provided anonymized with only nationality and gender acknowledged. The allele frequencies were calculated under Hardy-Weinberg equilibrium. The range of allele frequencies was 0.0009–0.5389. Heterozygosity ranged from 0.6204 to 0.8759, probability of identity from 0.0271 to 0.2100, and probability of paternity exclusion from 0.3645 to 0.7579. The information provided in this paper concerns the Myanmarese population in Thailand and could be used for forensic statistical analysis and further individual identification.