40 results on '"Bidmos MA"'
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2. Evaluation of standards for sex estimation using measurements obtained from reconstructed computed tomography images of the femur of contemporary Black South Africans.
- Author
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Ujaddughe OM, Haberfeld J, Bidmos MA, and Olateju OI
- Abstract
Dimensions of the pelvic and skull bones are known to be sexually dimorphic in various population groups. The recovery of these bones is potentially beneficial in estimating the sex in forensic cases. Since both bones are not always available for forensic analysis, standards for sex estimation must be established for other bones of the postcranial skeleton. Previous studies have reported that postcranial skeletal elements (e.g. femur) perform like the pelvis and better than the cranium in sex estimation. Thus, this study explored the potential of CT-derived femoral measurements in sex estimation in a South African population. The sample consisted of 280 contemporary Black South Africans (50% sex ratio) whose scan reports are stored in the Radiology Department of Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg, South Africa. The Xiris and IntelliSpace software was used to reconstruct the images into 3D formats from which measurements were taken. Previously derived sex estimation equations of the femur were tested using data from the current study and these equations presented low average classification accuracies. Using discriminant function and logistic regression analyses, new sex estimation equations were formulated, and these new equations yielded average sex estimation classification accuracies of between 82.5 and 91.4% (by multivariable logistic regression) and 79.3-84.3% (by multivariable discriminant function). The results indicate that population-specific femoral measurements obtained by CT are more reliable than those obtained by direct osteometry and that the femur has a high sexual dimorphism with relevant forensic applications., Competing Interests: Declarations. Ethical approval: Ethical approval with number M220108 was obtained from the Human Research Ethics Committee (HREC) of the University of the Witwatersrand, Johannesburg. Conflict of interest: The authors declare no conflict of interest., (© 2025. The Author(s).)
- Published
- 2025
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3. Machine learning and discriminant function analysis in the formulation of generic models for sex prediction using patella measurements.
- Author
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Bidmos MA, Olateju OI, Latiff S, Rahman T, and Chowdhury MEH
- Subjects
- Female, Humans, Male, Discriminant Analysis, Forensic Anthropology methods, Sex Characteristics, Skull anatomy & histology, Patella anatomy & histology, Sex Determination by Skeleton methods
- Abstract
Sex prediction from bone measurements that display sexual dimorphism is one of the most important aspects of forensic anthropology. Some bones like the skull and pelvis display distinct morphological traits that are based on shape. These morphological traits which are sexually dimorphic across different population groups have been shown to provide an acceptably high degree of accuracy in the prediction of sex. A sample of 100 patella of Mixed Ancestry South Africans (MASA) was collected from the Dart collection. Six parameters: maximum height (maxh), maximum breadth (maxw), maximum thickness (maxt), the height of articular facet (haf), lateral articular facet breadth (lafb), and medial articular facet breath (mafb) were used in this study. Stepwise and direct discriminant function analyses were performed for measurements that exhibited significant differences between male and female mean measurements, and the "leave-one-out" approach was used for validation. Moreover, we have used eight classical machine learning techniques along with feature ranking techniques to identify the best feature combinations for sex prediction. A stacking machine learning technique was trained and validated to classify the sex of the subject. Here, we have used the top performing three ML classifiers as base learners and the predictions of these models were used as inputs to different machine learning classifiers as meta learners to make the final decision. The measurements of the patella of South Africans are sexually dimorphic and this observation is consistent with previous studies on the patella of different countries. The range of average accuracies obtained for pooled multivariate discriminant function equations is 81.9-84.2%, while the stacking ML technique provides 90.8% accuracy which compares well with those presented for previous studies in other parts of the world. In conclusion, the models proposed in this study from measurements of the patella of different population groups in South Africa are useful resent with reasonably high average accuracies., (© 2022. The Author(s).)
- Published
- 2023
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4. Sex estimation from dimensions of the base of the skull in Black South Africans.
- Author
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Dayal MR, Billings BK, Brits D, Abdallah A, Spocter MA, and Bidmos MA
- Subjects
- Black People, Discriminant Analysis, Female, Forensic Anthropology methods, Humans, Male, Sex Characteristics, Skull anatomy & histology, South Africa epidemiology, Sex Determination by Skeleton methods
- Abstract
The pelvis and the skull are the two most utilised skeletal elements to estimate sex from skeletonised remains due to their sexually dimorphic traits. However, as increasingly more fragmented remains have been presented for analyses, other bones and their fragments have now been subjected to analyses for sex estimation. In the skull particularly, the base has shown to survive harsh conditions. In this study the foramen magnum region was explored in Black South Africans to estimate sex during forensic analyses. Seven measurements of the foramen magnum and surrounding areas were measured in 120 male and female crania and subjected to discriminant function analyses. The average accuracies for the stepwise discriminant functions ranged from 60-71% whilst the average accuracies for the direct discriminant functions ranged from 63-69%. The average accuracies obtained in this study are similar to other studies performed using the foramen magnum. However, these average accuracies are much lower than other skeletal elements that have been used for sex estimation in South Africans. Thus, the equations in this study should be used with caution and only in the absence of more accurate elements. The cranial base has always shown to have a low to moderate expression of sexual dimorphism. The cranial base of Black South Africans is no different.
- Published
- 2022
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5. Prevalence and global trends of polypharmacy among people living with HIV: a systematic review and meta-analysis.
- Author
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Danjuma MI, Adegboye OA, Aboughalia A, Soliman N, Almishal R, Abdul H, Mohamed MFH, Elshafie MN, AlKhal A, Elzouki A, Al-Saud A, Chaponda M, and Bidmos MA
- Abstract
Background: There has been a rising prevalence of polypharmacy among people living with HIV (PLWH). Uncertainty however remains regarding the exact estimates of polypharmacy among these cohorts of patients., Methods: We conducted a systematic search of PubMed; EMBASE, CROI, Cochrane Database of Systematic Reviews; Science Citation Index and Database of Abstracts of Reviews of Effects for studies between 1 January 2000 and 30 June 2021 that reported on the prevalence of polypharmacy (ingestion of > 5 non-ART medications) among PLWH on antiretroviral therapy regimen (ART). Prevalence of polypharmacy among HIV-positive patients on ART with Clopper-Pearson 95% confidence intervals were presented. The heterogeneity between studies was evaluated using I 2 and τ 2 statistics., Results: One hundred ninety-seven studies were initially identified, 23 met the inclusion criteria enrolling 55,988 PLWH, of which 76.7% [95% confidence interval (CI): 76.4-77.1] were male. The overall pooled prevalence of polypharmacy among PLWH was 33% (95% CI: 25-42%) ( I
2 = 100%, τ2 = 0.9170, p < 0.0001). Prevalence of polypharmacy is higher in the Americas (44%, 95% CI: 27-63%) ( I2 = 100%, τ2 = 1.0886, p < 0.01) than Europe (29%, 95% CI: 20-40%) ( I2 = 100%, τ2 = 0.7944, p < 0.01)., Conclusion: The pooled prevalence estimates from this synthesis established that polypharmacy is a significant and rising problem among PLWH. The exact interventions that are likely to significantly mitigate its effect remain uncertain and will need exploration by future prospective and systematic studies., Registration: PROSPERO: CRD42020170071 ., Plain Language Summary: Background: In people living with HIV (PLWH), what is the prevalence of polypharmacy and is this influenced by sociodemographic factors? Methods and Results: In this systematic review and meta-analysis of 23 studies comprising 55,988 participants, we have for the first time found an estimated polypharmacy pooled prevalence of 33% among PLWH. There was a relatively higher pooled prevalence of polypharmacy among the America's compared with European cohorts of PLWH. Conclusion: Polypharmacy among PLWH is a rising morbidity that needs urgent intervention both at policy and patient levels of care., Competing Interests: Competing interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s), 2022.)- Published
- 2022
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6. Accuracies of discriminant function equations for sex estimation using long bones of upper extremities.
- Author
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Bidmos MA and Mazengenya P
- Subjects
- Body Remains, Discriminant Analysis, Humans, Reproducibility of Results, South Africa ethnology, Humerus anatomy & histology, Radius anatomy & histology, Sex Determination by Skeleton methods, Ulna anatomy & histology
- Abstract
One of the scopes of practice of forensic anthropologists is the estimation of sex from skeletal remains. As a result, population-specific discriminant function equations have been developed from measurements of various bones of the human skeletons. Steyn, Patriquin (Forensic Sci Int 191 (1-3):113, 2009) noted that the lack of skeletal collections and data from most parts of the world has made this process impractical. Previous attempts to develop global discriminant function equations from measurements of the pelvis showed that population-specific equations are not necessary as equations derived from other populations yielded high sex estimation scores when applied to a different population. However, information on the suitability and applicability of generalised equations in sex estimation using long bones is still scarce. It is, therefore, the aim of this study to assess the accuracies of population-specific discriminant function equations derived from measurements of long bones of the upper limb of South African population groups. Data analysed in the current study were obtained from Mokoena, Billings, Bidmos, Mazengenya (Forensic Sci Int 278:404, 2017) and Mokoena, Billings, Gibbon, Bidmos, Mazengenya (Science & Justice 6(59):660-666, 2019) in which a total sample of 988 bones (humeri, radii, and ulnae) of South Africans of African descent (SAAD), South Africans of European descent (SAED) and Mixed Ancestry South Africans (MASA) were measured. Stepwise and direct discriminant function analyses were performed on the pooled data. Each function was used to estimate the sex of cases in each population group separately and average accuracies calculated. Thereafter, population-specific discriminant function equations were formulated for each population group and then applied to other population groups. The average accuracies of functions for pooled data ranged between 80.7 and 86.5%. The cross-validation average accuracies remained unchanged for most functions, confirming the validity of derived functions. A drop in average accuracies (0.8-5.3%) was observed when the functions were tested on a sample of SAAD while increased average accuracy was observed for the SAED and MASA (0.5-6.9%). When population-specific functions for a particular population group were applied to other groups, a wide range of a drop in average accuracies was observed (1.3 to 22.4%). This thereby confirms that population-specific equations should not be applied to other population groups. However, discriminant function equations from the pooled data of South Africans are accurate in the estimation of sex and efforts should be made towards the development and validation of such equations from as many bones of the human skeleton.
- Published
- 2021
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7. Morphometric profile of tendocalcaneus of South Africans of European ancestry using a cadaveric approach.
- Author
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Latiff S, Bidmos MA, and Olateju OI
- Subjects
- Cadaver, Female, Humans, Lower Extremity, Male, Reproducibility of Results, Dissection, Tendons
- Abstract
Background: Tendocalcaneus is a strong tendon that is vital for bipedalism in humans. Despite its tremendous strength, the tendocalcaneus is prone to damage and degeneration causing mobility problems and pain. Morphometric dimension of the tendocalcaneus is of benefit to the surgical repair and reconstruction of the damaged tendon. Cadaveric approach provides a realistic method for determining tendocalcaneus morphometry and as at present only two cadaveric studies on Indian population is available. Thus this study presents data on tendocalcaneus morphometry in South Africans of European ancestry using a cadaveric approach., Materials and Methods: A total of 66 lower limbs (32 left and 34 right legs) sourced from 49 male and female cadavers were used. After careful dissection of the posterior aspect of leg, the medial and lateral length, distal width, distal circumference and proximal width of the tendocalcaneus were measured., Results: The data showed a high degree of reproducibility indicating that the measurements obtained using cadaveric approach were precise and accurate. There was no difference in measurements between the sides. Measurements in the males were generally higher than in the females. Strong associations were observed between the paired measurements of the medial and lateral tendon length and between the distal width and distal circumference., Conclusions: The data obtained will be useful in predicting tendocalcaneus size during the surgical reconstruction of the tendocalcaneus.
- Published
- 2021
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8. Avoidability of drug-induced liver injury (DILI) in an elderly hospital cohort with cases assessed for causality by the updated RUCAM score.
- Author
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Danjuma MI, Almasri H, Alshokri S, Khir FK, Elmalik A, Battikh NG, Abdallah IMH, Elshafei M, Fatima H, Mohamed MFH, Maghoub Y, Hussain T, Kamal I, Anwer Z, Bidmos MA, and Elzouki AN
- Subjects
- Aged, Aged, 80 and over, Chemical and Drug Induced Liver Injury diagnosis, Drug-Related Side Effects and Adverse Reactions diagnosis, Female, Humans, Liver metabolism, Male, Middle Aged, Prospective Studies, Chemical and Drug Induced Liver Injury etiology, Chemical and Drug Induced Liver Injury prevention & control, Drug-Related Side Effects and Adverse Reactions epidemiology, General Practitioners, Liver drug effects
- Abstract
Background: Drug-induced liver injury (DILI) represents an increasing morbidity in the general population, but more so in the elderly cohort of patients. Despite this, the concept of its prevention through prospective analysis has largely remained unexamined. We evaluated the utility of recently validated adverse drug reactions (ADR) avoidability tool in a cohort of elderly patients with DILI., Methods: We examined 38 DILI-drug pairs from n=38 patients in a prospective cohort of patients presenting with adverse drug reactions to a Weill Cornell-affiliated tertiary hospital between February 2019 and January 2020. DILI outcomes were adjudicated by the updated Roussel Uclaf Causality Assessment Method (RUCAM). Two clinical pharmacologists and two general physicians utilized the Liverpool adverse drug reactions avoidability tool (LAAT) and the modified Hallas tools to rate the preventability of DILI-drug pairs. Inter-rater, exact agreement proportions, as well as intraclass correlation coefficients were generated and expressed as ordinal outcomes., Results: The cases examined for the determination of DILI avoidability had probability likelihood of "probable" or "highly probable" by the updated RUCAM scale. Examination of the 38 DILI-drug pairs (n= 38 patients) resulted in a total of 152 ordinal outcome decisions. We found about 32.3% (50/152) and 34.2% (52/152) of DILI-drug pairs were rated as "avoidable" ("probable" or "definite") by the LAAT and the modified Hallas tools respectively. The overall median Krippendorf's kappa with the LAAT was 0.61 (SE 0.12, CI 0.36, 0.85) and for modified Hallas tool was 0.53 (SE 0.18; CI 0.16, 0.89). The inter-rater correlation coefficient (ICC) for the LAAT and modified Hallas were 0.50 [0.32, 0.65] and 0.63 [0.48, 0.76] respectively. Exact pairwise agreement was present in 30/38 (IQR 29.5, 34.5), and 28/38 (IQR 27.5-35.5) of DILI-ADR pairs using the LAAT and modified Hallas tools respectively., Conclusion: We found a significant proportion of drug-induced liver injury adjudicated by the updated RUCAM scale in elderly hospitalized cohort of patients were avoidable with significant implication for therapeutic commissioning as well as cost effectiveness interventions in this cohort of patients.
- Published
- 2020
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9. Forensic utility of cranial measurements in stature reconstruction in South Africans of European descent.
- Author
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Bidmos MA and Adebesin AA
- Subjects
- Body Height, Female, Humans, Male, Regression Analysis, South Africa, Forensic Anthropology, Sex Characteristics, Skull anatomy & histology
- Abstract
The height of an individual (stature) is one of the biological profiles that is estimated as part of human identification process from various components of the human skeleton. The anatomical method is often used for this purpose when a complete and intact skeleton is available for forensic analysis because it is accurate. Since complete skeletons are seldom present in most forensic cases, the mathematical method, which shows linear relationship between stature and bone measurements, becomes the method of choice. Population and sex-specific regression equations for stature estimation have been formulated using intact and fragmentary long bones amongst South African whites and blacks. Individual and combinations of measurements of other skeletal elements including bones of the feet have also been used in the formulation of regression equations. However, few studies have utilized measurements of the skull for stature reconstruction. Skeletal height, calculated from a suite of measurements, was regressed on six cranial measurements. Basibregmatic height and basion-nasion length presented with the highest correlation coefficient for an individual variable in males (0.50) and females (0.48), respectively. The range of correlation coefficient from multivariate analyses in males (0.58-0.63) is similar to that obtained in females (0.55-0.62). The standard error of estimates of the equations, a measure of the accuracy of the equations, for male sample (6.74-7.09) was slightly higher than that for females (5.47-5.89). Regression equations presented in this study should be used with caution in forensic cases when only the skull is available for human identification. Significance of main findings: 1. Skull measurements show low to moderate correlation with stature. 2. Use of skull dimensions is advised only in the absence of intact long bones and other skeletal elements in South Africa.
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- 2020
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10. A comparison of the direct and indirect methods of estimating skeletal height from tibial fragments in black South Africans.
- Author
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Spies AJ, Bidmos MA, and Brits D
- Subjects
- Black People, Female, Humans, Male, Regression Analysis, Body Height, Forensic Anthropology, Sex Characteristics, Tibia anatomy & histology
- Abstract
The estimation of maximum bone length from its fragments is important in forensic anthropology as these length estimates can be used to estimate the total skeletal height (TSH), and thereby stature, of unknown skeletal remains. This is known as the indirect method of stature estimation. Alternatively, TSH can be estimated directly from bone fragments without first estimating maximum bone length. While regression equations for estimating maximum bone length from its fragments exist for long bones of the upper and lower limbs, these equations are population- and sex-specific and their use on populations other than the one they were derived from is not recommended. The aim of this study was therefore to develop formulae for estimating maximum tibial length from its fragments in black South Africans, which previously did not exist, and to compare the accuracies of the direct and indirect methods of estimating TSH from tibial fragments. Several measurements representing fragments were measured on the tibiae of 99 male and 99 female black South Africans, and equations estimating tibial length from these measurements were derived. Correlation coefficients of each equation were significant, and all equations estimated tibial length with moderate to high accuracy. A comparison of the standard errors of estimate (SEEs) between the direct and indirect methods of stature estimation indicate that the direct method is more accurate and should be used to estimate stature from tibial fragments when such equations exist.
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- 2020
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11. Efficacy of sodium-glucose co-transporter 2 inhibitors in patients with type II diabetes: A protocol for systematic review of randomised controlled clinical trials utilising a generalised pairwise modelling methodology.
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Danjuma MI, Shokri SA, Saud AIYA, Elshafei MNA, Fatima H, Doi S, and Bidmos MA
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- Bias, Data Interpretation, Statistical, Humans, Randomized Controlled Trials as Topic, Systematic Reviews as Topic, Diabetes Mellitus, Type 2 drug therapy, Hypoglycemic Agents therapeutic use, Sodium-Glucose Transporter 2 Inhibitors therapeutic use
- Abstract
Background: Recent systematic reviews have evaluated the efficacy of sodium-glucose co-transporter 2 inhibitors (SGLT2) inhibitors (SGLT2I) in improving glycaemic control and mortality in patients with type II diabetes mellitus. None have incorporated the most recent study or utilized the generalized pairwise modeling methodology network meta-analysis (NMA), as well as a novel bias risk assessment approach., Methods: We propose to conduct literature search of all randomized controlled clinical trials published in English language evaluating the efficacy of (SGLT2I) versus placebo or usual standard of care from the inception of following databases to September 30, 2019: Controlled Clinical Trials Cochrane Controlled Trials Register (CCTR), Cochrane Database of Systematic Reviews (CDSR), EMBASE, Database of Abstracts of Reviews of Effectiveness (DARE), PubMed. Two reviewers will independently search these databases to identify studies that satisfy pre-specified eligibility criteria. Study bias risk assessment amongst other methodology quality evaluation of the studies will be carried out using a novel risk bias assessment tool., Results: We anticipate that the result of this review will provide additional insight into the ranking of the efficacy of various (SGLT2I) in type II diabetic patients especially as it relates to mortality, glycemic control, and body weight reduction., Conclusion: The result of this review will be useful informing therapeutic decisions by policy makers with regards to commissioning of diabetic care.Prospero registration number: CRD42019139708.
- Published
- 2019
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12. Development of discriminant functions to estimate sex in upper limb bones for mixed ancestry South Africans.
- Author
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Mokoena P, Billings BK, Gibbon V, Bidmos MA, and Mazengenya P
- Subjects
- Adult, Aged, Discriminant Analysis, Female, Humans, Male, Middle Aged, Racial Groups, South Africa ethnology, Arm Bones anatomy & histology, Forensic Anthropology methods, Sex Characteristics, Sex Determination by Skeleton methods
- Abstract
South Africa has one of the highest murder rates in the world, which is associated with an increasing number of unidentified individuals. Forensic anthropologists can assist in these cases to reduce the number of potential victims the remains may belong to. Sex estimation potentially decreases the number of possible victims by half. The mixed ancestry population in South Africa is the second largest group of people; however, there remains a paucity of data and population-specific methods for sex estimation in this group. The aim of this study was to assess the potential for metrices obtained around the nutrient foramen and the maximum length of upper limb long bones to estimate sex in mixed ancestry South Africans using discriminant function analysis. A total of 328 humeri, radii and ulnae from individuals of mixed ancestry were analysed. Sex was correctly classified with an average classification accuracy of 84.3% in the humeri, 88.3% for radii and 83.5% for the ulnae. Total length was the single best predictor of sex; the combination of total length with dimensions related to the nutrient foramen produced high classification accuracies in the current study. Overall, sexual dimorphism was observed in mixed ancestry South Africans upper limb long bones. The findings of this study further emphasise the need for population-specific standards of sexing in an attempt to improve current methods of forensic identification of descendants., (Copyright © 2019 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.)
- Published
- 2019
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13. Using tibial fragments to reconstruct the total skeletal height of black South Africans.
- Author
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Spies AJ, Bidmos MA, and Brits D
- Subjects
- Female, Forensic Anthropology, Humans, Male, Regression Analysis, Sex Characteristics, South Africa, Black People, Body Height, Tibia anatomy & histology
- Abstract
Stature is an important component of the biological profile of unknown skeletal remains and regression equations for estimating stature have been derived for a number of bones. However, bones are rarely recovered intact in both forensic and archaeological cases, and regression formulae for fragmentary remains have therefore been developed. These equations are, however, both sex- and population-specific, and while formulae exist for many populations, those using fragmentary tibiae do not exist for black South Africans. The aim of this study was therefore to establish regression equations for estimating total skeletal height (TSH), and thereby stature, from tibial fragments in a black South African population. A sample of 99 male and 99 female black South African skeletons were obtained from the Raymond A. Dart Collection of Human Skeletons and the TSH of each skeleton was calculated using the anatomical method. Eleven additional measurements representing tibial fragments were taken on each tibia, and both uni- and multivariate equations were established for estimating TSH from these fragments. All tibial variables were significantly, positively correlated with TSH, and equation correlations ranged between 0.41 and 0.91. The range of standard errors of estimate for the derived sex-specific (3.43-5.06 cm) and sex-pooled (3.44-5.94 cm) multivariate equations were slightly larger than those reported for intact tibiae in black (2.78-3.06 cm) and white (2.59-3.16 cm) South Africans. All uni- and multivariate-equations estimated TSH with moderate to high accuracy, which indicates that in the absence of intact tibiae, the equations presented in this study can be used to give accurate estimates of TSH, and thereby stature, for black South Africans., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
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14. Measurements of the talus in the assessment of population affinity.
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Bidmos MA, Dayal MR, and Adegboye OA
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- Discriminant Analysis, Female, Forensic Anthropology, Humans, Logistic Models, Male, South Africa, Black People, Talus anatomy & histology, White People
- Abstract
As part of their routine work, forensic anthropologists are expected to report population affinity as part of the biological profile of an individual. The skull is the most widely used bone for the estimation of population affinity but it is not always present in a forensic case. Thus, other bones that preserve well have been shown to give a good indication of either the sex or population affinity of an individual. In this study, the potential of measurements of the talus was investigated for the purpose of estimating population affinity in South Africans. Nine measurements from two hundred and twenty tali of South African Africans (SAA) and South African Whites (SAW) from the Raymond A. Dart Collection of Human Skeletons were used. Direct and step-wise discriminant function and logistic regression analyses were carried out using SPSS and SAS. Talar length was the best single variable for discriminating between these two groups for males while in females the head height was the best single predictor. Average accuracies for correct population affinity classification using logistic regression analysis were higher than those obtained from discriminant function analysis. This study was the first of its type to employ discriminant function analyses and logistic regression analyses to estimate the population affinity of an individual from the talus. Thus these equations can now be used by South African anthropologists when estimating the population affinity of dismembered or damaged or incomplete skeletal remains of SAA and SAW., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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15. Dimensions around the nutrient foramina of the tibia and fibula in the estimation of sex.
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Fasemore MD, Bidmos MA, Mokoena P, Imam A, Billings BK, and Mazengenya P
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- Adult, Aged, Black People, Female, Forensic Anthropology, Humans, Male, Middle Aged, South Africa, White People, Young Adult, Fibula anatomy & histology, Sex Determination by Skeleton methods, Tibia anatomy & histology
- Abstract
Sex estimation from skeletal remains is one of the key components in establishing a biological profile and consequent identification of an individual in a forensic and medico-legal practice. The use of dimensions around the nutrient foramen in instances where long bones may be fragmented and damaged is of benefit due to the fact that the nutrient foramen is easily identifiable and may be preserved on the shaft of long bones. This study is an investigation of the usefulness of various measurements around the nutrient foramen of the tibia and fibula of South Africans in an attempt to develop osteometric standards for sex estimation. The sample included 206 tibiae and 204 fibulae of South African Africans (SAA) and South African whites (SAW) procured from the Raymond A. Dart Collection of Human Skeletons based at the University of the Witwatersrand. Sex was correctly classified for the tibia with an accuracy ranging between 79-82% in SAA and 84-88% in SAW, with the circumference at the level of the nutrient foramen as the single best predictor of sex in both populations. An accuracy ranging from 69 to 74% in SAA and 70-77% in SAW was observed for the combined measurements on the fibula. The current study confirms the usefulness of measurements around the nutrient foramen of the tibia in the assignment of sex. However functions of the fibula generally performed poorly and should be used with caution., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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16. Assessing the use of the anatomical method for the estimation of sub-adult stature in Black South Africans.
- Author
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Brits D, Manger PR, and Bidmos MA
- Subjects
- Adolescent, Black People, Child, Diaphyses anatomy & histology, Diaphyses diagnostic imaging, Female, Forensic Anthropology, Humans, Magnetic Resonance Imaging, Male, Regression Analysis, South Africa, Body Height, Bone and Bones anatomy & histology, Bone and Bones diagnostic imaging
- Abstract
Stature estimation is rarely attempted in sub-adults due to the general lack of available standards as a result of the dearth of sufficiently large sub-adult skeletal collections with known demographic information. To overcome this problem sub-adult research mainly relies on modern imaging modalities. In the current study Magnetic Resonance Imaging (MRI) scans were used to assess the use of the anatomical method for stature estimation in sub-adults. A total of 53 Black South African sub-adult males (n=24) and females (n=29) aged between 10 and 17 years participated in the study by voluntarily completing a full-body MRI scan. A stadiometer was used to measure living stature prior to all MRI scans. Skeletal elements that contribute directly to stature were measured from the MRI scans using OsiriX and summed to compute the total skeletal height. Total skeletal height was calculated using the diaphyseal, maximum and physiological long bone lengths and correlated to living stature using Pearson's correlations. Subsequently least squares regression equations were generated for the estimation of sub-adult stature. Results indicated strong, statistically significant positive correlations between living stature and total skeletal heights in sub-adult males, females and a combined sex sample. The regression equations were characterized by small standard error of estimates which are comparable to that reported for Black South African adults. Based on these results the anatomical method can be used to accurately describe living stature in Black South African sub-adults. This method is therefore encouraged as it will add valuable information when dealing with unknown sub-adult skeletal remains., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2018
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17. The accuracy of the anatomical method for stature estimation in Black South African females.
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Brits D, Manger PR, and Bidmos MA
- Subjects
- Adult, Bone and Bones anatomy & histology, Female, Forensic Anthropology methods, Humans, Magnetic Resonance Imaging, Middle Aged, Regression Analysis, South Africa, Whole Body Imaging, Young Adult, Black People, Body Height, Bone and Bones diagnostic imaging
- Abstract
The anatomical method is considered the most accurate stature estimation method, but investigation has shown that it continuously underestimates stature. This underestimation is believed to be related to the use of universal soft tissue correction factors. Therefore, the aim of this study was to assess the accuracy of the soft tissue correction factors in a living population of Black South African females and to subsequently calculate a new soft tissue correction factor, specific for stature estimation in this population group. Thirty Black South African adult females voluntarily participated in this study and underwent a full body Magnetic Resonance Imaging (MRI) scan. Living stature was measured with a stadiometer and total skeletal height (TSH) was calculated from the MRI measurements. Stature was estimated from the TSH of each participant using Fully's (1956) [17], Raxter et al.'s (2006) [38] and Bidmos and Manger's (2012) [5] methods. Results indicated strong, statistically significant positive correlations between living and estimated statures, however, paired t-tests revealed that living stature was significantly underestimated using Fully's and Raxter et al.'s methods, while the method by Bidmos and Manger significantly overestimated stature. A lack of statistically significant correlations between soft tissue correction factors and the total skeletal height was found. Likewise, an absence of statistically significant correlations between age and the estimation error, with and without age adjustments were also observed. A new soft tissue correction factor, specific for stature estimation in Black South African females was calculated. The newly proposed regression equation presented improved stature estimation accuracies for this population group., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
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18. Sex estimation using dimensions around the nutrient foramen of the long bones of the arm and forearm in South Africans.
- Author
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Mokoena P, Billings BK, Bidmos MA, and Mazengenya P
- Subjects
- Adult, Aged, Black People, Discriminant Analysis, Female, Forensic Anthropology, Humans, Male, Middle Aged, South Africa, White People, Young Adult, Arm Bones anatomy & histology, Sex Determination by Skeleton methods
- Abstract
South Africa has had an increase in rates of crime, interpersonal violence and homicide since the introduction of democracy in 1994. Forensic osteological standards was lacking for South Africans of different population groups necessitating the generation of new standards for forensic identification of individuals from skeletal remains. For these reasons, there is a concerted demand for methods of identifying skeletal remains with sex being amongst the most important of the biological characteristics required. The nutrient foramen has been used to estimate sex in lower limb long bones with much accuracy but this has not been demonstrated in the upper limb long bones. The aim of this study was to develop osteometric standards for sex estimation from measurements around the nutrient foramen of the arm and forearm bones of South Africans of different population affinities. A total of 660 bones consisting of humeri, radii and ulnae of black South Africans and white South Africans were assessed for sex estimation using dimensions related to the nutrient foramen. Sex was correctly classified with a range of 84-85% for the humerus and 83-88% for the arm bones. The study showed that length measurements were more sexually dimorphic than width dimensions in South Africans, as length was consistently selected as the best predictor of sex in all bones. However, the average accuracy increased when length was used in combination with measurements related to the nutrient foramen. In conclusion, the dimensions of upper limb long bones that are directly related to the nutrient foramen are sexually dimorphic and are useful in the estimation of sex in South Africans, with the highest accuracy shown in the white South African population group., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
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- View/download PDF
19. Stature estimation from the femur and tibia in Black South African sub-adults.
- Author
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Brits DM, Bidmos MA, and Manger PR
- Subjects
- Adolescent, Black People, Child, Diaphyses anatomy & histology, Female, Femur anatomy & histology, Forensic Anthropology, Humans, Least-Squares Analysis, Magnetic Resonance Imaging, Male, Regression Analysis, South Africa, Tibia anatomy & histology, Body Height, Diaphyses diagnostic imaging, Femur diagnostic imaging, Tibia diagnostic imaging
- Abstract
Stature estimation can play a role in the positive identification of unknown individuals and as such it is routinely assessed during the examination of adult remains. Unfortunately, this is not a standard procedure when dealing with sub-adult remains due to the general lack of standard procedures for the estimation of sub-adult stature. The aim of this study was therefore to derive regression equations for the estimation of stature in black South African sub-adults. Fifty nine black South African sub-adult males and females, aged 10-17 years, voluntarily participated in the study by undergoing a full body Magnetic Resonance Imaging (MRI) scan. Living stature was measured with a stadiometer and the maximum and diaphyseal lengths of the femur and tibia were measured from the MRI scans using the image processing software OsiriX. Pearson's correlation coefficients and linear least square regression analyses were used to assess the correlations between living stature and the measurements and to generate sub-adult stature estimation equations for males, females and a combined sex sample. Measurements of the femur, tibia and the combined measures thereof showed strong statistically significant positive correlations with living stature, while the obtained regression equations were characterized by low standard error of estimates. The strong correlations and low standard error of estimates are comparable to stature estimation models reported for Black South African adults and therefore these variables can be considered good estimators of sub-adult stature which will contribute valuable information to the biological profile of unidentified sub-adult skeletal remains., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2017
- Full Text
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20. Plasma cell leukaemia and HIV co-infection: profile of patients and experience at Universitas Academic Hospital in Bloemfontein, South Africa.
- Author
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Bidmos MA, Joubert S, van Jaarsveld MF, and Louw VJ
- Subjects
- Adult, Aged, Female, HIV Infections diagnosis, HIV Infections drug therapy, Humans, Male, Middle Aged, Retrospective Studies, South Africa epidemiology, Treatment Outcome, HIV Infections complications, HIV Infections epidemiology, Hospitals, University, Leukemia, Plasma Cell complications, Leukemia, Plasma Cell epidemiology
- Abstract
Plasma cell leukaemia (PCL) is a rare condition with high mortality. HIV-positive patients have a propensity to develop malignancy; however, the occurrence of PCL with HIV infection in South Africa has not been documented. We describe patients with PCL in Universitas Hospital in Bloemfontein, South Africa, and report two new cases of HIV infection concurrent with PCL. A retrospective case series of PCL patients (2006-2012) seen at our Clinical Haematology unit is reported. Patient files were used to obtain information. The median age of patients (n = 9) was 51 years, and 66.7 % of cases were of African ethnicity. The condition was equally distributed between genders. Two patients were HIV positive. Both received combination antiretroviral therapy. The diagnosis of PCL was usually made as an incidental finding, subsequently confirmed on bone marrow aspirate and trephine. Deranged haematological and biochemical parameters, including severe anaemia, hypoalbuminaemia, and hyper-cellular bone marrow, were observed. Only one patient improved markedly on treatment, and remains alive at the time of writing. PCL shows poor response to treatment and predominates among Africans. The small sample size made it difficult to determine whether co-infection with HIV was a coincidental finding or the two diseases are pathophysiologically linked.
- Published
- 2013
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21. New soft tissue correction factors for stature estimation: results from magnetic resonance imaging.
- Author
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Bidmos MA and Manger PR
- Subjects
- Adolescent, Adult, Calcaneus anatomy & histology, Femur anatomy & histology, Forensic Anthropology methods, Humans, Male, Middle Aged, Regression Analysis, Skull anatomy & histology, Spine anatomy & histology, Talus anatomy & histology, Tibia anatomy & histology, Young Adult, Adipose Tissue anatomy & histology, Anthropometry methods, Body Height, Magnetic Resonance Imaging, Subcutaneous Tissue anatomy & histology
- Abstract
In stature reconstruction using Fully's method, it is essential that a soft tissue correction factor be added to skeletal height in order to obtain an estimate of living stature. While some anthropologists consider Fully's method to be the most reliable for stature estimation, others consider it to be inadequate as it seems to be underestimating living stature, possibly due to an error in the magnitude of Fully's soft tissue factors. A recent study by Raxter and co-workers revised Fully's technique and also presented a new "universally applicable" soft tissue correction factor. The present study examines the reliability of soft tissue correction factors of Fully and Raxter et al. on a living sample of indigenous South African males. The current study is based on data collected from 28 indigenous South African (ISA) male volunteers. Standing height of each subject was measured using a stadiometer. Fully's method was used in the calculation of total skeletal height from a full body MRI scan of each subject. Subsequent analyses of the acquired data revealed that the previously derived soft tissue correction factors are not applicable to the studied sample, and why they are not applicable. The correction factors of Fully and Raxter et al. both significantly underestimate living stature in a living sample of indigenous South African males. Consequently, a new correction factor was calculated based on the prediction of living stature from TSH using regression analysis., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2012
- Full Text
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22. An assessment of the accuracy of discriminant function equations for sex determination of the femur and tibia from a South African population.
- Author
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Robinson MS and Bidmos MA
- Subjects
- Adult, Aged, Discriminant Analysis, Female, Forensic Anthropology, Humans, Male, Middle Aged, South Africa, Young Adult, Femur anatomy & histology, Sex Determination by Skeleton methods, Tibia anatomy & histology
- Abstract
The purpose of this study is to test the accuracy of seven discriminant function equations that have been derived by Steyn and Isçan for sex determination using measurements of the femur and tibia of South Africans of European descent (SAED). While the validity of some of the discriminant functions has been assessed by the authors who derived them, no previous independent study has been carried out to assess the accuracy of these equations. These equations have not been tested on skeletons located outside of the Gauteng province. A suite of measurements were taken on 272 femora and 256 tibiae obtained from four South African skeletal collections. The validity of each of the previously published equations for the femur was confirmed. However, two functions of the tibia showed low accuracy rates, most likely due to difficulties in recording the distal epiphyseal breadth measurement, and thus were found to be poor assessors of sex., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2011
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23. Fragmentary femora: evaluation of the accuracy of the direct and indirect methods in stature reconstruction.
- Author
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Bidmos MA
- Subjects
- Female, Forensic Anthropology methods, Humans, Male, Regression Analysis, South Africa, Body Height, Femur anatomy & histology
- Abstract
Selected measurements of the femur have been used in the derivation of regression equations for stature estimation in several populations. Various studies have indicated that stature can be estimated from fragmentary bones by either the direct or the indirect method. The direct method allows for the estimation of stature directly from individual or combination of measurements of fragments of the femur. However, the indirect method consists of two steps. An initial step which involves the estimation of maximum length of the femur from measurements of its fragments is followed by stature estimation from the estimated maximum length of the femur. While Steele noted that the indirect method provides a relatively more precise estimate of stature, none of the subsequent studies on stature reconstruction has addressed the issue of accuracy of the two methods. The current study utilized 120 complete skeletons obtained from the Raymond A. Dart Collection of Human Skeletons. Total skeletal height for each of the skeletons (TSH(Fully)) was calculated using the Fully's method. Measurements of fragments of the femur acquired from the current study were substituted into each of the previously derived equations for Indigenous South Africans (ISA) and South Africans of European Descent (SAED) in order to obtain an estimate of the skeletal height (TSH(Est)). Analyses were carried out separately for each group. An assessment of the differences between the estimated skeletal height (TSH(Est)) and the obtained skeletal height using the Fully's method (TSH(Fully)) was performed using the paired t test. While no significant difference was observed between TSH(Fully) and TSH(Est) for all equations (except one) used in the direct estimation of skeletal height, a number of indirect equations significantly overestimated TSH(Fully). These observations indicate that the direct method is more accurate than the indirect method. Since it is also less complicated, it is therefore the preferred of the two methods contrary to earlier recommendation made by Steele.
- Published
- 2009
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24. The history and composition of the Raymond A. Dart Collection of Human Skeletons at the University of the Witwatersrand, Johannesburg, South Africa.
- Author
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Dayal MR, Kegley AD, Strkalj G, Bidmos MA, and Kuykendall KL
- Subjects
- Adolescent, Adult, Cadaver, Child, Child, Preschool, Female, History, 20th Century, Humans, Infant, Infant, Newborn, Male, Middle Aged, Population Groups, South Africa, Anthropology, Physical history, Skeleton, Universities
- Abstract
The Raymond A. Dart Collection of Human Skeletons (Dart Collection) is housed in the School of Anatomical Sciences at the University of the Witwatersrand, Johannesburg, South Africa, and comprises one of the largest documented cadaver-derived human skeletal assemblages in the world. This collection originated in the early 1920s as a result of the efforts of Raymond Dart and continues to grow. The skeletons included represent varied indigenous and immigrant populations from southern Africa, Europe and Asia. This contribution documents the history of the collection and provides an updated inventory and demographic assessment of this valuable research collection. According to a recent inventory the Dart Collection currently comprises 2,605 skeletons representing individuals from regional SA African (76%), White (15%), Coloured (4%) and Indian (0.3%) populations. A large proportion of the skeletons (71%) represent males. The recorded ages at death range from the first year to over 100 years of age, but the majority of individuals died between the ages of 20 and 70. The Dart Collection has been affected by collection procedures based on availability. All of the cadavers collected before 1958, and large proportions subsequently, were derived from unclaimed bodies in regional South African hospitals. Some details of documentation (age at death, population group) are estimates and some aspects of the collection demographics (sex ratios) do not closely reflect any living South African population. Our inventory and analysis of the Dart Collection is aimed to assist researchers planning research on the materials from this collection.
- Published
- 2009
- Full Text
- View/download PDF
25. The skull and humerus in the determination of sex: reliability of discriminant function equations.
- Author
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Robinson MS and Bidmos MA
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Female, Forensic Anthropology methods, Humans, Male, Middle Aged, Reproducibility of Results, Young Adult, Discriminant Analysis, Humerus anatomy & histology, Sex Determination by Skeleton methods, Skull anatomy & histology
- Abstract
Sex determination plays a crucial role in the identification of human remains as it narrows the possibility for identification by 50%. The purpose of this study is to test the validity of five discriminant function equations, with accuracies of 80% and higher, that have been derived by Steyn and Işcan [M. Steyn, M.Y. Işcan, Sexual dimorphism in the crania and mandibles of South African Whites, Forensic Sci. Int. 98 (1998) 9-16; M. Steyn, M.Y. Işcan, Osteometric variation in the humerus: sexual dimorphism in South Africans, Forensic Sci. Int. 106 (1999) 77-85] for the skull and humerus of South Africans of European Descent (SAED). These equations were tested on different regional populations of SAED within South Africa. While the validity of some of the discriminant functions has been assessed by the authors who derived them, no other previous independent study has been carried out to assess the reliability of these equations. In addition, these equations have not been tested on skeletons located outside the Gauteng province. The study sample consisted of 230 skulls and 264 humeri of SAED obtained from four South African skeletal collections: Raymond A. Dart Collection of Human Skeletons (Johannesburg); Pretoria Bone Collection; Cape Town Skeletal Collection; and the Osteology Archive Student Collection (Stellenbosch). A total of 14 measurements (12 cranial and 2 humeral) were taken on these skeletal elements. The observed accuracies from the present study (72.0-95.5%), with the exception of one sample's accuracy, compared well with the original classification rates (80.2-92.5%) for most of the functions thereby confirming the validity of the discriminant function equations for sex determination for the skull and humerus of SAED, for SAED in all regions of South Africa.
- Published
- 2009
- Full Text
- View/download PDF
26. Metatarsals in the estimation of stature in South Africans.
- Author
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Bidmos MA
- Subjects
- Adult, Aged, Black People statistics & numerical data, Body Size, Calcaneus anatomy & histology, Cephalometry statistics & numerical data, Female, Forensic Anthropology methods, Humans, Male, Middle Aged, Regression Analysis, Skull anatomy & histology, South Africa ethnology, Tibia anatomy & histology, White People statistics & numerical data, Anthropometry methods, Body Height, Forensic Anthropology statistics & numerical data, Metatarsal Bones anatomy & histology
- Abstract
To date, only one study has investigated the potential of metatarsals in the estimation of stature for forensic purposes. The morphology of these bones from clinical and paleontological perspectives is well researched in different parts of the world including South Africa. The present study aimed at assessing the usefulness of metatarsals of South Africans in the estimation of stature. For this study, 226 complete skeletons obtained from the Raymond A. Dart Collection were used in the formulation of univariate and multivariate regression equations from six linear measurements of metatarsals. The standard error of estimate for these equations was lower than that obtained for fragments of long bones and other skeletal elements studied so far for stature estimation in South Africans with the exception of intact long bones. Therefore, regression equations presented in this study can provide a reliable estimate of stature in cases where intact long bones are not available for forensic analysis.
- Published
- 2008
- Full Text
- View/download PDF
27. Stature reconstruction using fragmentary femora in South Africans of European descent.
- Author
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Bidmos MA
- Subjects
- Adult, Aged, Europe ethnology, Female, Humans, Male, Middle Aged, Regression Analysis, Sex Characteristics, South Africa, Body Height, Femur anatomy & histology, Forensic Anthropology methods
- Abstract
It is well documented that the intact femur has the highest correlation with stature and as such has been widely used in the derivation of regression equations for stature estimation. As intact femur is not always present for analyses in forensic cases, it has become necessary to derive regression equations for the estimation of stature from fragments of this bone. Few studies have presented regression equations for stature estimation from fragments of the femur. Because these equations are population specific, it was the aim of this study to derive similar equations for estimation of stature and maximum length of femur from measurements of the femur of South Africans of European descent. A sample of 50 male and 50 female complete skeletons were obtained from the Raymond A. Dart Collection of Human Skeletons. Total skeletal height for each of the skeletons was calculated using the Fully's method. Six variables were measured on each femur which included the vertical neck diameter, upper breadth of femur, epicondylar breadth, bicondylar breadth, lateral condyle length, and medial condyle length. Regression equations for the estimation of stature are presented. The range of standard error of estimate for these equations (3.71-5.31) was slightly higher than those obtained for intact long bones (2.13-3.79). It is therefore suggested that in the absence of intact femur, regression equations derived from the present study can provide a reliable estimate of adult stature.
- Published
- 2008
- Full Text
- View/download PDF
28. Estimation of stature using fragmentary femora in indigenous South Africans.
- Author
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Bidmos MA
- Subjects
- Adult, Ethnicity, Female, Humans, Male, Middle Aged, Regression Analysis, Sex Characteristics, Sex Determination by Skeleton, Body Height, Femur anatomy & histology, Forensic Anthropology methods
- Abstract
Intact long bones of the upper and lower extremities have been used in the derivation of regression equations for the estimation of stature in different population groups. These bones are sometimes presented to forensic anthropologists in different states of fragmentation thereby making the derived equations unusable. This has necessitated the need to assess the usefulness of measurements of fragments of long bones (e.g., femur) in the estimation of stature. While few studies have reported such equations, which are population and sex specific, it was the aim of this study to derive equations based on measurements of commonly preserved fragments of the femur for the indigenous South African population group. A total of 100 complete skeletons, equally distributed by sex, were obtained from the Raymond A. Dart collection of human skeletons. Stature was estimated for each of the skeleton using the Fully's method (Fully in Ann Med Leg 35:266-273, 1956). Regression equation for the estimation of stature and maximum length of the femur were derived from six measurements of the femur. The standard error of estimate for regression equations for stature estimation (3.72-4.38) was slightly higher than that presented for intact femur. This study confirms the usefulness of fragments of the femur of indigenous South Africans in the estimation of stature.
- Published
- 2008
- Full Text
- View/download PDF
29. An assessment of sex using the skull of black South Africans by discriminant function analysis.
- Author
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Dayal MR, Spocter MA, and Bidmos MA
- Subjects
- Adult, Aged, Anthropometry methods, Discriminant Analysis, Female, Humans, Male, Mandible anatomy & histology, Middle Aged, South Africa, Black People ethnology, Sex Characteristics, Sex Determination by Skeleton methods, Skull anatomy & histology
- Abstract
The derivation of discriminant function equations for skeletal elements of South African populations continues to be an area of interest to both forensic anthropologists and skeletal biologists alike. The skull of black South Africans has previously been subjected to discriminant function analysis, using four measurements and two indices; however, no equations were derived to address the issue of sex determination. Recently Franklin, Freedman and Milne [2005. Sexual dimorphism and discriminant function sexing in indigenous South African crania. HOMO J. Comp. Hum. Biol. 55, 213-228] used the crania of black South Africans, in a three-dimensional approach, with eight linear measurements to investigate sex determination. This study, although valuable, requires the use of highly technical and expensive morphometric equipment that renders it less feasible in South Africa. In response to this, our study uses traditional anthropometric measurements and equipment to address the question of sex determination from the crania and mandible of blacks. One hundred and twenty non-pathological skulls were randomly selected from the Raymond Dart Collection of Human Skeletons, equally distributed by sex and belonging to individuals whose age at death ranges between 25 and 70 years. Fourteen cranial and six mandibular measurements were subjected to discriminant function analyses and discriminant function equations were derived for sex determination. Average accuracies ranged between 80% and 85% and were on par with that obtained in previous studies. Our study shows that traditional methods provide average accuracies that are comparable to those obtained using more complex techniques.
- Published
- 2008
- Full Text
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30. Using tibia fragments from South Africans of European descent to estimate maximum tibia length and stature.
- Author
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Chibba K and Bidmos MA
- Subjects
- Aged, Europe ethnology, Female, Humans, Male, Middle Aged, Regression Analysis, Sex Characteristics, South Africa, Body Height, Forensic Anthropology methods, Tibia anatomy & histology
- Abstract
Intact long limb bones have been used in the derivation of regression equations for stature assessment in different population groups. Since intact long bones are not always present for analyses in forensic cases, it has become necessary to derive regression equations for the estimation of stature from the fragments of these bones which are obtained in forensic and archaeological cases. Regression equations have been derived for stature estimation from fragments of the tibia. Since these equations are population specific, it was the aim of this study to derive similar equations for estimation of stature and maximum tibia length from measurements of different fragments of tibia of South Africans of European descent. Analyses were based on a sample of 50 male and 50 female complete skeletons of adult South Africans of European descent. Total skeletal height for the individual skeletons was measured using the Fully's (anatomical) method. Six variables were measured on the tibia which included the medial tibial condyle lengths and breadths, lateral tibial condyle lengths and breadths, proximal breadth and distal breadth. Univariate and multivariate regression equations were formulated for estimation of total skeletal height (and subsequent estimation of living stature) and maximum tibial length from measurements of the tibia. The standard errors of estimate for the equations were higher than those obtained for intact long bones which when present in forensic cases should be used for stature estimation. In the absence of intact long bones, the equations derived from the present study can provide a reliable estimate of skeletal height and living stature.
- Published
- 2007
- Full Text
- View/download PDF
31. Skeletal height reconstruction from measurements of the skull in indigenous South Africans.
- Author
-
Ryan I and Bidmos MA
- Subjects
- Adult, Aged, Black People, Female, Humans, Male, Middle Aged, Regression Analysis, Sex Characteristics, South Africa, Body Height, Cephalometry methods, Forensic Anthropology methods, Skull anatomy & histology
- Abstract
Stature reconstruction is important as it provides a forensic anthropological estimate of the height of a person in the living state; playing a vital role in the identification of individuals from their skeletal remains. Regression formulae for stature estimation have been generated for indigenous South Africans based on measurements of long bones of upper and lower extremities and the calcaneus. Since these bones are not always available for forensic analysis, it became necessary to use other bones such as the skull for stature estimation. The aim of the present study was to investigate the usefulness of certain measurements of the skull of indigenous South Africans in the estimation of adult stature. Ninety-nine complete skeletons obtained from the Raymond A. Dart Collection, School of Anatomical Sciences of the University of the Witwatersrand, were used. Total skeletal height (TSH) was calculated for each skeleton using the Fully's (anatomical) method. Furthermore, six variables were measured on each skull. TSH was regressed onto these cranial measurements in order to obtain regression formulae. The correlation coefficients obtained ranged between 0.40 and 0.54. The range of the standard errors of estimate from the current study (4.37 and 6.24) is high in comparison to that obtained for stature estimation based on intact long bones and the calcaneus. Therefore, the equations presented in this study should be used with caution in forensic cases when only the skull is available for human identification.
- Published
- 2007
- Full Text
- View/download PDF
32. Discriminating sex in South African blacks using patella dimensions.
- Author
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Dayal MR and Bidmos MA
- Subjects
- Discriminant Analysis, Female, Humans, Male, South Africa, Black People, Forensic Anthropology methods, Patella anatomy & histology, Sex Characteristics
- Abstract
For many years, sex determination has been carried out on skeletal remains to identify individuals in forensic cases and to assess populations in archaeological cases. Since it has been shown that not all bones are found in a forensic case, discriminant function equations should be derived for all bones of the body to assist in sex determination. Numerous studies have shown the usefulness of bones of the lower extremity (e.g. femur, tibia) in sex determination using discriminant function analysis, but the use of patella measurements has not been extensively investigated for this purpose. It is therefore the aim of this study to derive discriminant function equations for sex determination from measurements of the patella of South African blacks as represented in the Raymond A. Dart Collection of Human Skeletons. A total sample of 120 (60 male, 60 female) patellae were measured using six measurements. The Statistical Product and Service Solutions (SPSS) program was used to derive the equations. Stepwise and direct analyses were performed with the highest rate of classification of 85% thereby making the patella useful for sex determination. Thus, the proposed equations derived from this study should be used with caution and only on the South African black population group.
- Published
- 2005
33. On the non-equivalence of documented cadaver lengths to living stature estimates based on Fully's method on bones in the Raymond A. Dart Collection.
- Author
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Bidmos MA
- Subjects
- Adult, Aged, Black People, Bone and Bones pathology, Cadaver, Female, Forensic Pathology methods, Humans, Male, Middle Aged, Regression Analysis, South Africa, White People, Anthropometry methods, Body Height, Bone and Bones anatomy & histology
- Abstract
Regression equations for stature estimation have been derived from documented cadaver lengths available as part of the demographic information in the catalogue of skeletonised remains in different collections around the world. The Raymond A. Dart Collection is one such collection, but the reliability of documented cadaver lengths in it has been previously questioned. The aim of this study was to compare these lengths with estimated living stature using Fully's anatomical method. Living stature was estimated with this method from a total of 156 complete skeletons obtained from the Collection. These heights were then compared with the documented cadaver lengths. It was observed that the documented cadaver lengths were significantly higher than the estimated living stature using Fully's method.
- Published
- 2005
34. Patella measurements of South African whites as sex assessors.
- Author
-
Bidmos MA, Steinberg N, and Kuykendall KL
- Subjects
- Female, Humans, Male, Reference Values, South Africa, Patella anatomy & histology, Sex Characteristics, White People
- Abstract
This study uses metrical characteristics of the patella to derive population specific equations for sex determination in South Africa. Six measurements were taken from 120 normal and undamaged left patellae in a sample of known race, equally distributed by sex, obtained from the Raymond A Dart collection of human skeletons. These data were subjected to discriminant analysis. Maximum height and maximum breadth were selected in the stepwise analysis with an average accuracy of 83% in correct sex classification. Four functions were derived from the direct analysis with a range of average accuracy between 77% and 85%. While most individual variables showed high misclassification rates and may not be useful on their own, maximum height and maximum breadth have an average accuracy of 85 and 79%, respectively.
- Published
- 2005
- Full Text
- View/download PDF
35. Further evidence to show population specificity of discriminant function equations for sex determination using the talus of South African blacks.
- Author
-
Bidmos MA and Dayal MR
- Subjects
- Adolescent, Adult, Aged, Discriminant Analysis, Female, Humans, Male, Middle Aged, Reproducibility of Results, South Africa, Black People, Forensic Anthropology methods, Sex Characteristics, Talus anatomy & histology
- Abstract
Several studies have shown that osteometric differences exist between different population groups. Thus, discriminant function equations derived for the determination of sex from skeletal elements are population specific. In a previous study, the authors derived such equations from nine measurements of the talus of South African whites with high levels of average accuracies. The validity of some of the equations was tested on data collected from a South African black sample that consisted of 120 tali, equally distributed by sex, derived from the Raymond A. Dart Collection of Human Skeletons. The average accuracies dropped significantly. This necessitated the derivation of new equations for the South African black population and the average accuracies obtained ranged between 80% and 89%. The validity of the equations derived from the present study was tested using the leave-one-out classification and two independent samples (1 and 2). The applicability of the equations with very high classification rate from the present study was tested on Independent sample 1 of 10 white tali with poor results. The result of the validity of these equations on an Independent sample 2 of 10 black tali revealed acceptably high average accuracies in correct classification thereby supporting earlier observations on population specificity of discriminant function equations.
- Published
- 2004
36. Discriminant function sexing of fragmentary femur of South African blacks.
- Author
-
Asala SA, Bidmos MA, and Dayal MR
- Subjects
- Anthropometry, Discriminant Analysis, Female, Humans, Male, South Africa, Black People, Femur anatomy & histology, Forensic Anthropology methods, Sex Characteristics
- Abstract
When fragmentary and incomplete bones are all that are available to the forensic anthropologist for use in sex determination, non-metric and metric sex discriminating parameters that have been derived from complete bones may be of little use. In such circumstances, sex discriminating metric methods that are of specific application to fragmentary bones will be more useful. Since such studies have not been systematically carried out in bones of South African blacks, the aim of this study was to begin to provide such data. Two hundred and twenty left femurs of black South Africans were obtained from the Raymond A. Dart Collection of African Skeleton, School of Anatomical Sciences, University of the Witwatersrand, South Africa. Five variables from the upper end of the femur and three variables from the lower end of the femur were measured and subjected to univariate and multivariate discriminant function analyses. The vertical head diameter and the medial condylar length were most successful in sex identification from the upper and lower ends of the femur respectively. The combined variables were more useful than the use of variables individually. Discriminant function score equations were derived for individual and combined variables from the upper and lower ends of the femur of the South African blacks.
- Published
- 2004
- Full Text
- View/download PDF
37. Sexual dimorphism of the calcaneus of South African blacks.
- Author
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Bidmos MA and Asala SA
- Subjects
- Adult, Aged, Discriminant Analysis, Female, Humans, Male, Middle Aged, Reproducibility of Results, South Africa ethnology, Black People, Calcaneus anatomy & histology, Forensic Anthropology methods, Sex Characteristics
- Abstract
Forensic anthropology is a rapidly growing field in South Africa and skeletal biologists are often called upon by the police to assist in personal identification from skeletal remains, which are recovered in suspected cases of homicide and suicide and in mass disaster. Measurements of the calcaneus have been shown to be sexually dimorphic in South African whites. Since the validity of discriminant function equations in sex determination is population specific, the aim of the present study was to derive similar equations for the calcanei of the South African blacks. The bones that were used in this study were obtained from the Raymond A. Dart Collection of Human Skeletons, School of Anatomical Sciences, University of the Witwatersrand, Johannesburg. One hundred and sixteen (116) intact and non-pathological calcanei, consisting of 58 males and 58 females and belonging to individuals whose age at death ranged between 22 and 75 years, were selected by the simple random sampling technique. The measured variables included the maximum length, the load arm length, the dorsal articular facet length, the body height, the maximum height, the cuboidal facet height, the middle breadth, the dorsal articular facet breadth and the maximum breadth. Discriminant function analyses were done using the Statistical Product and Service Solutions (SPSS) program. All measured parameters of the calcaneus showed significant sexual differences. Length measurements were found to be the most sexually dimorphic. Combinations of variables provided better estimate of sex (79%-86%) than individual variables (64%-79%).
- Published
- 2004
38. Sex determination from the talus of South african whites by discriminant function analysis.
- Author
-
Bidmos MA and Dayal MR
- Subjects
- Adolescent, Adult, Aged, Discriminant Analysis, Female, Humans, Male, Middle Aged, South Africa, Anthropometry methods, Forensic Anthropology methods, Sex Characteristics, Talus anatomy & histology, White People
- Abstract
The field of forensic anthropology involves the building of an antemortem profile of an individual from skeletal remains. This includes sex and race determination and age and stature estimation. Since most bones that are conventionally used for sex determination are often recovered either in a fragmented or incomplete state, it has become necessary to use denser bones that are often recovered intact, eg, the patella, calcaneus, and talus. Thus the aim of this study is to assess the sex-determining ability of each of the measurements of the talus and derive discriminant function equations for sex determination in the South African white population. Sixty male and 60 female tali of South African whites obtained from the Raymond A. Dart Collection of Human Skeletons were used. Nine measurements were taken on each talus. Descriptive statistics and discriminant function analysis were performed on the acquired data. The basic statistics showed that all measurements were sexually dimorphic. Univariate, stepwise, and direct discriminant function equations were generated for use in sex determination. The level of average accuracy of sex classification was 80% to 82% for the univariate method, 85% to 88% for the stepwise method, and 81% to 86% for the direct method. It is concluded that the talus of South African whites is useful for sex determination.
- Published
- 2003
- Full Text
- View/download PDF
39. Discriminant function sexing of the calcaneus of the South African whites.
- Author
-
Bidmos MA and Asala SA
- Subjects
- Adult, Aged, Discriminant Analysis, Female, Humans, Male, Middle Aged, South Africa, Anthropometry methods, Calcaneus anatomy & histology, Forensic Anthropology methods, Sex Characteristics, White People
- Abstract
The skull and some postcranial elements, such as the humerus, femur, and tibia, have been used in their intact states for sex determination in forensic and archaeological cases. But, in practice, these bones are often recovered in fragmented states, which render them unsuitable for use in sex determination. The calcaneus is a compact bone that is able to withstand high tensile forces. Some of its parameters have been used for sex determination in American whites and blacks (1) and Italians (2). This bone has not been used for sex determination in the South African white population. Therefore, the aim of this study was to assess the degree of sexual dimorphism of the calcaneus of the South African white population sample, derive discriminant function score equations for use in sex determination, and determine the level of accuracy of its sex-determining ability. Nine parameters were measured on each pair of 53 male and 60 female calcanei of known South African white skeletons, obtained by a random sampling technique from the Raymond A. Dart Collection of Human Skeletons, School of Anatomical Sciences, University of the Witwatersrand, Johannesburg. Basic statistic and discriminant function analysis was performed on the acquired data. The basic statistics showed that all measured parameters were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 73 to 86% for the univariate method, 81 to 91% for the stepwise method, and 82 to 92% for the direct method. It is concluded that the calcaneus is useful for sex determination in the South African white population.
- Published
- 2003
40. An unusual origin of supernumerary renal arteries: case report.
- Author
-
Asala SA, Masumbuko-Kahamba N, and Bidmos MA
- Subjects
- Humans, Iliac Artery abnormalities, Renal Artery abnormalities
- Abstract
Patent left and right supernumerary inferior polar renal arteries were found in a dissection room cadaver. Both arteries originated from the left common iliac artery. This is an unusual form of origin of these arteries in the presence of an apparently normal ascent and position of the two kidneys.
- Published
- 2001
- Full Text
- View/download PDF
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