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1.
Int J Legal Med ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386033

RESUMO

Morphological analysis in forensic facial comparison was recently validated for judicial use. However, no image quality assurance systems exist for this purpose, despite image triage being considered the best practice approach. Hence, this study aimed at testing a semi-quantitative scoring method to assess image quality and investigated facial image resolution and lighting quality quantitatively in a context of forensic facial comparison. For this purpose, 400 facial comparison photographic and CCTV image pools developed from the Wits Face Database were used. These facial images were analysed in prior studies that investigated the validity of morphological analysis. A semi-quantitative image quality scoring system was adapted and tested on the above sample and compared across correct and incorrect matches obtained as part of previous studies using a logistic regression model. In addition, facial images were cropped to the closest pixel comprising the face, head and neck areas; then, a face-to-image pixel proportion was calculated as an estimator of resolution quality; and pixel exposure qualities were obtained to be compared to facial comparison outcomes. Ideal and high image quality scores were related to correctness of matches, while low-quality scores were related to incorrect matches. High pixel proportions were related to true matches and low exposure was related to false positives, while high exposure was related to false negatives. These results suggest that an easy method for image triage could be employed by scoring image quality. Quantitative measures should be investigated further for thresholding quality suitability for confidence of facial comparisons.

2.
Int J Legal Med ; 138(3): 983-995, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38279991

RESUMO

Age assessment of migrants is crucial, particularly for unaccompanied foreign minors, a population facing legal, social, and humanitarian challenges. Despite existing guidelines, there is no unified protocol in Europe for age assessment.The Forensic Anthropology Society of Europe (FASE) conducted a comprehensive questionnaire to understand age estimation practices in Europe. The questionnaire had sections focusing on the professional background of respondents, annual assessment numbers, requesting parties and reasons, types of examinations conducted (e.g., physical, radiological), followed protocols, age estimation methods, and questions on how age estimates are reported.The questionnaire's findings reveal extensive engagement of the forensic community in age assessment in the living, emphasizing multidisciplinary approaches. However, there seems to be an incomplete appreciation of AGFAD guidelines. Commonalities exist in examination methodologies and imaging tests. However, discrepancies emerged among respondents regarding sexual maturity assessment and reporting assessment results. Given the increasing importance of age assessment, especially for migrant child protection, the study stresses the need for a unified protocol across European countries. This can only be achieved if EU Member States wholeheartedly embrace the fundamental principles outlined in EU Directives and conduct medical age assessments aligned with recognized standards such as the AGFAD guidelines.


Assuntos
Refugiados , Migrantes , Criança , Humanos , Menores de Idade , Europa (Continente) , Antropologia Forense , Determinação da Idade pelo Esqueleto
3.
Anthropol Anz ; 81(2): 233-239, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-37869964

RESUMO

Diagnosis of specific infectious diseases in the skeleton is often difficult and relies on expert opinion. Statistics is not often used as a tool to assist in such diagnoses, and therefore this study aimed at employing data mining and machine learning in the form of decision tree analysis to aid in recognizing tuberculosis (TB) in skeletal remains and find patterns of skeletal involvement. The sample included 387 modern South African individuals (n = 207 individuals known to have died of TB and n = 180 as a control group) which were scored for the presence or absence of 21 skeletal lesions documented to be associated with TB. A pruned decision tree classification analysis was done to detect significant patterns and associations between variables which produced a model with a moderate classification rate based on four of the variables. As expected, vertebral changes were selected first, followed by rib, acetabular and lastly cranial changes. As a proof of concept, it was shown that machine learning was able to identify patterns of changes in TB skeletons versus a control group. However, further investigation into the use of machine learning in assessing skeletal changes associated with specific diseases is needed.


Assuntos
Tuberculose , Humanos , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Esqueleto/patologia , Árvores de Decisões
4.
Nature ; 625(7995): 540-547, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38030719

RESUMO

The expansion of people speaking Bantu languages is the most dramatic demographic event in Late Holocene Africa and fundamentally reshaped the linguistic, cultural and biological landscape of the continent1-7. With a comprehensive genomic dataset, including newly generated data of modern-day and ancient DNA from previously unsampled regions in Africa, we contribute insights into this expansion that started 6,000-4,000 years ago in western Africa. We genotyped 1,763 participants, including 1,526 Bantu speakers from 147 populations across 14 African countries, and generated whole-genome sequences from 12 Late Iron Age individuals8. We show that genetic diversity amongst Bantu-speaking populations declines with distance from western Africa, with current-day Zambia and the Democratic Republic of Congo as possible crossroads of interaction. Using spatially explicit methods9 and correlating genetic, linguistic and geographical data, we provide cross-disciplinary support for a serial-founder migration model. We further show that Bantu speakers received significant gene flow from local groups in regions they expanded into. Our genetic dataset provides an exhaustive modern-day African comparative dataset for ancient DNA studies10 and will be important to a wide range of disciplines from science and humanities, as well as to the medical sector studying human genetic variation and health in African and African-descendant populations.


Assuntos
DNA Antigo , Emigração e Imigração , Genética Populacional , Idioma , Humanos , África Ocidental , Conjuntos de Dados como Assunto , República Democrática do Congo , DNA Antigo/análise , Emigração e Imigração/história , Efeito Fundador , Fluxo Gênico/genética , Variação Genética/genética , História Antiga , Idioma/história , Linguística/história , Zâmbia , Mapeamento Geográfico
5.
Int J Legal Med ; 137(3): 743-752, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36929197

RESUMO

An age-at-death estimation method using the first rib may be particularly advantageous as this rib is relatively easy to identify, not easily damaged postmortem, and associated with less mechanical stresses compared to other age indicators. Previously, mixed results have been achieved using the first rib to estimate age-at-death. This study aimed to develop and test an age-at-death estimation method using the first rib. An identified modern black South African sample of 260 skeletons were used to collect age-related data from the first rib. Multiple linear regression analysis equations were created from this data for male, female, and combined samples. When tested on a hold-out sample, equations generated mean inaccuracies of 7-13 years for point estimates. The 95% confidence intervals contained the true age in 11-33% of individuals depending on the equation used, but wider intervals generated using 95% prediction intervals contained true ages for 100% of individuals. Point estimate inaccuracies are comparable to other age-at-death estimation methods and may be useful if single indicator estimation is unavoidable in the case of missing or damaged bones. However, combined methods that use indicators from many areas of the skeleton are preferable and may reduce interval widths.


Assuntos
Determinação da Idade pelo Esqueleto , Antropologia Forense , Adulto , Humanos , Masculino , Feminino , África do Sul , Antropologia Forense/métodos , Determinação da Idade pelo Esqueleto/métodos , Costelas/anatomia & histologia , População Negra
6.
Int J Paleopathol ; 40: 20-32, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36444782

RESUMO

OBJECTIVE: This study assessed the sensitivity and specificity of skeletal lesions to accurately diagnose TB in a pre-antibiotic South African skeletal sample. MATERIALS: A total of 435 skeletons of individuals who died before 1950 from the Raymond A. Dart Collection of Human Skeletons. 176 died of TB, 109 died of other pulmonary diseases, and 150 died of other causes. METHODS: The presence / absence of 23 skeletal lesions were assessed for differences in frequency between groups. Sensitivities and specificities were calculated and compared to Dangvard Pedersen et al. (2019). RESULTS: Lesions on the ventral surface of thoracic and lumbar vertebral bodies were observed significantly more often in TB and pulmonary cases than in other cause of death group and yielded a 55% probability of a true TB diagnosis, if observed. An association between skeletal lesions and TB was found for rib and vertebral lesions. CONCLUSIONS: The results suggest that even when not documented to have died of TB, TB-related changes are observed in many individuals in a South African skeletal sample, indicating that they may have been infected with the disease. SIGNIFICANCE: The study provides information that can assist palaeopathologists in making inferences about the prevalence of TB in past populations. LIMITATIONS: Sample sizes were small, and the inclusion of a pulmonary disease group may have confounded the results. SUGGESTIONS FOR FURTHER RESEARCH: The selection of a control group without any possible contact with TB may improve the results and should be investigated.


Assuntos
Doenças Ósseas , Tuberculose , Humanos , África do Sul , Tuberculose/patologia , Esqueleto/patologia , Doenças Ósseas/patologia , Antibacterianos
7.
SA J Radiol ; 26(1): 2516, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483672

RESUMO

Radiological diagnostic errors are common and may have severe consequences. Understanding these errors and their possible causes is crucial for optimising patient care and improving radiological training. Recent postmortem studies using an animal model highlighted the difficulties associated with accurate fracture diagnosis using radiological imaging. The present study aimed to highlight the fact that certain fractures are easily missed on CT scans in a clinical setting and that caution is advised. A few such cases were discussed to raise the level of suspicion to prevent similar diagnostic errors in future cases. Records of adult patients from the radiological department at an academic hospital in South Africa were retrospectively reviewed. Case studies were selected by identifying records of patients between January and June 2021 where traumatic fractures were missed during initial imaging interpretation but later detected during secondary analysis or on follow-up scans. Seven cases were identified, and the possible causes of the diagnostic errors were evaluated by reviewing the history of each case, level of experience of each reporting radiologist, scan quality and time of day that initial imaging interpretation of each scan was performed. The causes were multifactorial, potentially including a lack of experience, fatigue, heavy workloads or inadequate training of the initial reporting radiologist. Identifying these causes, openly discussing them and providing additional training for radiologists may aid in reducing these errors. Contribution: This article aimed to use case examples of missed injuries on CT scanning of patients in a South African emergency trauma setting in order to highlight and provide insight into common errors in scan interpretation, their causes and possible means of mitigating them.

8.
PLoS One ; 17(9): e0274127, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36054122

RESUMO

Linear measurements taken from bony landmarks are often utilised in facial approximation (FA) to estimate and plan the placement of overlying soft tissue features. This process similarly guides craniofacial superimposition (CFS) practices. Knowledge of how hard and soft tissue features spatially relate around the mouth region is, however, limited. Geometric morphometric techniques have thus been used to investigate size and shape variation in dentition-to-lip mouth morphology in a South African population. Twenty landmarks (twelve dentition, eight lips) were digitised, using cone-beam CT images of the anterior craniofacial complex in a Frankfurt/Frankfort position, for 147 individuals aged between 20 and 75 years. Principal Component Analysis and Canonical Variate Analysis established that much shape variation exists. A two-way ANOVA identified significant (p < 0.0001) population and sex variation with mouth shape. Black individuals presented with thicker lips, with the oral fissure aligning closely to the dental occlusion. Oral fissure position for white individuals corresponded to the inferior one-quarter (females) or one-sixth (males) of the maxillary central incisor crowns. Males presented larger dimensions than females, but females had a greater lip-to-teeth height ratio than their male counterparts. A pooled within-group regression analysis assessed the effect of age on the dentition and lips and found that it had a significant (p < 0.0001) impact on mouth shape. Ageing was associated with a reduced lip and teeth height, increased mouth width, and a lowered oral fissure and cheilion placement. The generated mean shape data, with metric guides, offer a visual and numerical guide that builds on existing FA and CFS standards, enhancing our understanding of hard and soft tissue relationships.


Assuntos
Lábio , Adulto , Idoso , Tomografia Computadorizada de Feixe Cônico , Dentição , Face/anatomia & histologia , Face/diagnóstico por imagem , Feminino , Humanos , Lábio/anatomia & histologia , Lábio/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Int J Legal Med ; 136(5): 1417-1430, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35654876

RESUMO

Victims of violent crime often have evidence of sharp force trauma (SFT) which needs to be examined to accurately investigate these cases. The abilities of CTs, X-rays, and Lodox to detect skeletal SFT defects and the minimum number of impacts were assessed, as were their abilities to macroscopically interpret SFT with the aim of identifying the class of weapon used. Ten pigs were, post-mortem, stabbed using a kitchen knife on one side of the body and chopped using a panga on the other side. They were then scanned and macerated. The number of SFT defects, type of SFT, and minimum number of impacts identifiable osteologically were recorded, as well as when using each imaging modality. CTs were most sensitive for detecting stab and chop defects (56.7% and 78.3%, respectively) and the minimum number of impacts (82.8%), while X-rays were least sensitive (17.2% for stab wounds, 46.5% for chop marks, and 43.5% for impacts). Lodox detected 26.8% of stab defects, 59.3% of chop marks, and 58.4% of impacts. The type of SFT for more than 70.0% of identified defects was correctly classified using all methods, while only Lodox had moderate sensitivities for stab wounds (52.4%). When radiological assessments of skeletal SFT are required, CTs should be performed, but Lodox can be used as an alternative. However, dry bone analyses still produce the best results and should be performed whenever possible. Macroscopic interpretations of skeletal SFT to broadly determine the class of weapon used is possible radiologically.


Assuntos
Ferimentos Perfurantes , Animais , Radiografia , Sensibilidade e Especificidade , Suínos , Tomografia Computadorizada por Raios X/métodos , Ferimentos Perfurantes/diagnóstico por imagem , Raios X
10.
Med Sci Law ; 62(2): 134-143, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34825618

RESUMO

The accurate radiological detection of skeletal trauma is crucial for the investigation of blunt force trauma (BFT) cases. The sensitivities of CTs, X-rays and Lodox in identifying BFT fractures and minimum number of impacts in pigs, used as proxies for adult humans, were assessed. Ten human sized pig carcasses were struck with a mallet and scanned, after which the number of fractures and minimum number of impacts detected radiologically were recorded. Pig carcasses were then macerated, and the defleshed, skeletonized remains were considered the gold standard as far as number and location of fractures were concerned. CTs were most sensitive in identifying fractures and impacts in all body regions, with overall sensitivities of 55.4% and 71.5% respectively, while X-rays and Lodox had sensitivities of 25.8% and 29.3% for fractures, and 43.5% and 41.1% for impacts, respectively. All modalities were highly specific for identifying fractures (CT: 99.1%; X-ray: 98.9%; Lodox: 99.4%). CTs should be used to analyze blunt force trauma when a radiological assessment is required, but an examination of the defleshed bones remains the gold standard for the deceased whenever feasible. X-rays and Lodox have limited diagnostic value in these cases and relying on them to detect fractures may compromise the accurate forensic investigation of blunt trauma victims. However, the use of Lodox for initial screening of major trauma is still of value. Sensitivities are generally higher for detecting fractures in pigs compared to piglets, indicating that increased diagnostic value is achieved when imaging pigs compared to piglets.


Assuntos
Fraturas Ósseas , Ferimentos não Penetrantes , Animais , Fraturas Ósseas/diagnóstico por imagem , Humanos , Radiografia , Sensibilidade e Especificidade , Suínos , Imagem Corporal Total , Ferimentos não Penetrantes/diagnóstico por imagem , Raios X
11.
Int J Legal Med ; 136(3): 739-751, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34767061

RESUMO

The mathematical method which will achieve the most accurate and precise age-at-death estimate from the adult skeleton is often debated. Some research promotes Bayesian analysis, which is widely considered better suited to the data construct of adult age-at-death distributions. Other research indicates that methods with less mathematical complexity produce equally accurate and precise age-at-death estimates. One of the advantages of Bayesian analysis is the ability to systematically combine multiple indicators, which is reported to improve the age-at-death estimate. Few comparisons exist between Bayesian analysis and less complex mathematical models when considering multiple skeletal indicators. This study aims to evaluate the performance of a Bayesian approach compared to a phase-based averaging method and linear regression analysis using multiple skeletal indicators. The three combination methods were constructed from age-at-death data collected from 330 adult skeletons contained in the Raymond A Dart and Pretoria Bone Collections in South Africa. These methods were tested and compared using a hold-out sample of 30 skeletons. As is frequently reported in literature, a balance between accuracy and precision was difficult to obtain from the three selected methods. However, the averaging and regression analysis methods outperformed the Bayesian approach in both accuracy and precision. Nevertheless, each method may be suited to its own unique situation-averaging to inform first impressions, multiple linear regression to achieve statistically defensible accuracies and precisions and Bayesian analysis to allow for cases where category adjustments or missing indicators are necessary.


Assuntos
Osso e Ossos , Modelos Teóricos , Adulto , Teorema de Bayes , Humanos , Análise de Regressão , África do Sul
12.
Biology (Basel) ; 10(12)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34943183

RESUMO

Global escalation of crime has necessitated the use of digital imagery to aid the identification of perpetrators. Forensic facial comparison (FFC) is increasingly employed, often relying on poor-quality images. In the absence of standardized criteria, especially in terms of video recordings, verification of the methodology is needed. This paper addresses aspects of FFC, discussing relevant terminology, investigating the validity and reliability of the FISWG morphological feature list using a new South African database, and advising on standards for CCTV equipment. Suboptimal conditions, including poor resolution, unfavorable angle of incidence, color, and lighting, affected the accuracy of FFC. Morphological analysis of photographs, standard CCTV, and eye-level CCTV showed improved performance in a strict iteration analysis, but not when using analogue CCTV images. Therefore, both strict and lenient iterations should be conducted, but FFC must be abandoned when a strict iteration performs worse than a lenient one. This threshold ought to be applied to the specific CCTV equipment to determine its utility. Chance-corrected accuracy was the most representative measure of accuracy, as opposed to the commonly used hit rate. While the use of automated systems is increasing, trained human observer-based morphological analysis, using the FISWG feature list and an Analysis, Comparison, Evaluation, and Verification (ACE-V) approach, should be the primary method of facial comparison.

13.
Sci Justice ; 61(6): 743-754, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34802648

RESUMO

Facial comparison is an important yet understudied discipline in forensics. The recommended method for facial comparison in a forensic setting involves morphological analysis (MA) with the use of a facial feature list. The performance of this approach has not been tested across various closed-circuit television (CCTV) conditions. This is of particular concern as video and image data available to law enforcement is often varied and of subpar conditions. The present study aimed at testing MA across two types of CCTV data, representing ideal and less than ideal settings, also assessing which particular shortcomings arose from less-than-ideal settings. The study was conducted on a subset of the Wits Face Database arranged in a total of 225 face pools. Each face pool consisted of a target image obtained from either a high-definition digital CCTV camera or a low-definition analogue CCTV camera in monochrome, contrasted to 10 possible matches. The face pools were analysed and scored using MA and confusion matrices were used to analyse the outcomes. A notably high chance corrected accuracy (CCA) (97.3%) and reliability (0.969) was identified across the digital CCTV sample, while in the analogue CCTV sample MA appeared to underperform both in accuracy (CCA: 33.1%) and reliability (0.529). The majority of the errors in scoring resulted in false negatives in the analogue sample (75.2%), while across both CCTV conditions false positives were low (digital: 0.3%; analogue: 1.2%). Even though hit rates appeared deceptively high in the analogue sample, the various measures of performance used and particularly the chance corrected accuracy highlighted its shortfalls. Overall, CCTV recording quality appears closely associated to MA performance, despite the favourable error rates when using the Facial Identification Scientific Working Group feature list.


Assuntos
Face , Medicina Legal , Face/anatomia & histologia , Humanos , Reprodutibilidade dos Testes , Televisão , Gravação em Vídeo
14.
Forensic Sci Int ; 328: 110995, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34583243

RESUMO

Identified (documented) osteological collections represent an important resource in the development of forensic anthropology standards and methods as well as a precious tool for learning and training of practitioners. Even though the number of papers presenting identified collections worldwide increases, many of the collections have still not been divulged to the scientific community in sufficient detail to ascertain their exact number. The Forensic Anthropology Society of Europe (FASE) therefore developed a tool that goes beyond sporadic publications: the FASE Map of Identified Osteological Collections, which is freely accessible and continuously updated and revised. The online map is available at http://forensicanthropology.eu/osteological-collections/. The map of skeletal collections was created in 2017 and currently displays information on 153 identified osteological collections (43 of them categorized as contemporary) located in 41 different countries. This article offers a short analysis of the type, geographical location and content of the collections included in the map. The aim of this article and the map as such is to provide a useful resource to facilitate research planning and teaching in forensic anthropology and related disciplines.


Assuntos
Antropologia Forense , Osso e Ossos , Europa (Continente) , Sociedades
15.
F1000Res ; 10: 131, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33815766

RESUMO

Forensic facial comparison is a commonly used, yet under-evaluated method employed in medicolegal contexts across the world. Testing the accuracy and reliability of facial comparisons requires large scale controlled and matching facial image databases. Databases that contain images of individuals on closed-circuit television (CCTV), with matching formal and informal photographs are needed for this type of research. Although many databases are available, the majority if not all are developed in order to improve facial recognition and face detection algorithms through machine learning, with very limited if any measure of standardisation. This paper aims to review the available databases and describe the development of a high resolution, standardised facial photograph and CCTV recording database of male Africans. The database is composed of a total of 6220 standardised and uncontrolled suboptimal facial photographs of 622 matching individuals in five different views, as well as corresponding CCTV footage of 334 individuals recorded under different realistic conditions. A detailed description of the composition and acquisition process of the database as well as its subdivisions and possible uses are provided. The challenges and limitations of developing this database are also highlighted, particularly with regard to obtaining CCTV video recordings and ethics for a database of faces. The application process to access the database is also briefly described.


Assuntos
Reconhecimento Facial , Televisão , Bases de Dados Factuais , Humanos , Masculino , Reprodutibilidade dos Testes , Gravação em Vídeo
16.
J Forensic Sci ; 66(4): 1220-1233, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33885153

RESUMO

Disguises are commonly used to mask a person's facial appearance in areas under closed-circuit television (CCTV) surveillance. While many studies attempted to understand the effects of disguises, such as hats and glasses, on facial recognition, limited studies have looked at disguises in forensic facial comparison. The aim of this study was to compare the outcomes of forensic facial comparison by morphological analysis (MA) in a CCTV sample with sunglasses and brimmed caps. The sample was obtained from the Wits Face Database and organized into 81 face pools of one target facial image wearing a disguise (cap or sunglasses) and 10 potential matching images. MA was conducted across face pools, and confusion matrices were used to assess the outcomes. Surprisingly, sunglasses had limited effect on MA performance both in accuracy (90.4%) and in reliability (κ = 0.798), while caps markedly decreased both accuracy (68.1%) and reliability (κ = 0.639). Error rates were associated primarily with false negatives in both samples (caps: 42.4%; sunglasses: 16.1%) despite the sample distribution favoring false-positive errors, which were very low (caps: 0.6%; sunglasses: 0%). Similarly to other studies, hats and caps were more harmful to correct identification when compared to sunglasses, which actually resulted in better accuracy than regular CCTV recordings. The effect of brimmed caps on accuracy was attributed to the overall loss of facial information caused. On training analysts, it may be helpful to instruct purposefully avoiding overreliance on easily disguised facial features, as other regions of the face also contain substantial feature information.


Assuntos
Vestuário , Óculos , Reconhecimento Facial , Ciências Forenses , Humanos , Fotografação , Gravação em Vídeo
17.
Int J Legal Med ; 135(5): 1965-1981, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33594456

RESUMO

Between the ever-increasing availability of surveillance evidence and expert-based forensic facial comparison being considered admissible in court, confirming its validity is paramount. Facial comparison is most commonly conducted using morphological analysis (MA), a largely untested feature-based approach. This study aimed at validating the current recommended practice of MA in both standardised and suboptimal surveillance samples. Face pools of 175 South African males were compiled with a series of facial photographs, using images from the Wits Face Database. The first 75 face pools consisted of wildtype (unstandardised) high-quality target photographs, while the remaining 100 face pools consisted of suboptimal closed-circuit television (CCTV) target images. Target images were compared to high-quality standardised photographs. Face pools were analysed using the Facial Identification Scientific Working Group's guidelines and feature list. Confusion matrices were used to determine the performance of MA in each cohort. MA was found highly accurate (chance-corrected accuracy (CCA): 99.1%) and reliable (κ = 0.921) in the photographic sample and less accurate (CCA: 82.6%) and reliable (κ = 0.743), in the CCTV sample. Higher false-positive and false-negative rates were noted for the CCTV sample, with the majority of errors resulting in false-negative outcomes. The decreased performance in the CCTV sample was attributed to various factors including image quality, angle of recording and lighting. Other studies testing facial comparison identified lower accuracies and reliability across various conditions. Better performance was found here and in other studies that included some form of facial feature list, reinforcing the importance of using a systematic facial feature list.


Assuntos
Reconhecimento Facial , Ciências Forenses/métodos , Guias como Assunto/normas , Fotografação , Televisão , Gravação em Vídeo , Adulto , Bases de Dados Factuais , Humanos , Masculino , Valor Preditivo dos Testes , Sensibilidade e Especificidade , África do Sul
18.
J Forensic Sci ; 66(2): 470-478, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33136310

RESUMO

Skull fractures are common in children both due to abuse and accidental incidences. The accurate detection of these fractures may therefore be critical. The aim of this study was to investigate the reliability of CT, X-ray, and Lodox® scans, the latter which has not previously been evaluated and is commonly employed in South Africa, in detecting the number, location and type of pediatric skull fractures. Blunt force trauma was inflicted with a mallet on ten piglet skulls, which were CT, X-ray, and Lodox® scanned and then macerated. The number, location, and type of skull fractures visible using each imaging modality, and on the cleaned skulls, were recorded. Sensitivities and specificities of each method were calculated. For fracture number and location, CTs had a sensitivity of 47.3%, X-rays 22.4% and Lodox® 23.3%. For fracture type, sensitivities were 46.1%, 16.6%, and 17.8% for CT, X-ray, and Lodox® , respectively. Specificities were high (92.5%-100%) which reduces the risk of incorrectly diagnosing fractures. However, low sensitivities increase the risk of failing to identify fractures and possible victims of abuse. Osteological analysis should preferably be the method of choice when evaluating pediatric skull trauma, and CTs should be used when osteological analysis is not feasible. If CT scanners are not available, X-rays and Lodox® may have to be used. In these cases, additional radiographic views of the skull are imperative and may increase the sensitivity of these methods, although they are not recommended to detect exact pediatric skull fracture number, location, and type.


Assuntos
Fraturas Cranianas/diagnóstico por imagem , Animais , Medicina Legal , Modelos Animais , Radiografia/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos , Tomografia Computadorizada por Raios X
19.
J Forensic Sci ; 66(2): 766-774, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33201522

RESUMO

South Africa is a country overwhelmed by crime and violence, with very high incidences of abuse against women and children. It is not often that a case of intimate partner homicide is seen in a forensic anthropological context. Here, we report on such a case where the remains of the victim had been buried for some time. The victim was a middle-aged female, while the suspect was a younger adult male. The deceased had suffered massive, repeated trauma during her lifetime with healed fractures and evidence of soft tissue trauma to virtually all parts of her body. A partly healed rib fracture indicates that the abuse continued until shortly before her death. She ultimately succumbed after suffering trauma to her head and face after reportedly being hit by a brick, evidence of which can be seen as perimortem fractures of the face. It is important for forensic anthropologists to identify specific patterns and report on the presence of healed fractures, as they can raise suspicion as to the possibility of chronic abuse. In this case, the evidence suggests a very long period of extreme and repeated trauma, which were apparently not reported or noticed by family members or the medical fraternity.


Assuntos
Consolidação da Fratura , Fraturas Múltiplas/patologia , Violência por Parceiro Íntimo , Abuso Físico , Adulto , Feminino , Homicídio , Humanos , Masculino , Pessoa de Meia-Idade , África do Sul
20.
Med Sci Law ; 61(3): 170-179, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33251942

RESUMO

Average facial soft-tissue thickness (FSTT) databanks are continuously developed and applied within craniofacial identification. This study considered and tested a subject-specific regression model alternative for estimating the FSTT values for oral midline landmarks using skeletal projection measurements. Measurements were taken from cone-beam computed tomography scans of 100 South African individuals (60 male, 40 female; Mage = 35 years). Regression equations incorporating sex categories were generated. This significantly improved the goodness-of-fit (r2-value). Validation tests compared the constructed regression models with mean FSTT data collected from this study, existing South African FSTT data, a universal total weighted mean approach with pooled demographic data and collection techniques and a regression model approach that uses bizygomatic width and maximum cranial breadth dimensions. The generated regression equations demonstrated individualised results, presenting a total mean inaccuracy (TMI) of 1.53 mm using dental projection measurements and 1.55 mm using cemento-enamel junction projection measurements. These slightly outperformed most tested mean models (TMI ranged from 1.42 to 4.43 mm), and substantially outperformed the pre-existing regression model approach (TMI = 5.12 mm). The newly devised regressions offer a subject-specific solution to FSTT estimation within a South African population. A continued development in sample size and validation testing may help substantiate its application within craniofacial identification.


Assuntos
Pontos de Referência Anatômicos , Cefalometria , Face/anatomia & histologia , Lábio/anatomia & histologia , Modelos Estatísticos , Adulto , Idoso , Precisão da Medição Dimensional , Feminino , Antropologia Forense/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , África do Sul/etnologia
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