Decision tree analysis for age estimation in living individuals: integrating cervical and dental radiographic evaluations within a South African population.

Age estimation in living individuals around the age of 18 years is medico-legally important in undocumented migrant cases and in countries like South Africa where many individuals are devoid of identification documents. Establishing whether an individual is younger than 18 years largely influences the legal procedure that should be followed in dealing with an undocumented individual. The aim of this study was to combine dental third molar and anterior inferior apophysis ossification data for purposes of age estimation, by applying a decision tree analysis. A sample comprising of 871 black South African individuals (n = 446 males, 425 = females) with ages ranging between 15 and 24 years was analyzed using panoramic and cephalometric radiographs. Variables related to the left upper and lower third molars and cervical vertebral ring apophysis ossification of C2, C3, and C4 vertebrae analyzed in previous studies were combined in a multifactorial approach. The data were analyzed using a pruned decision tree function for classification. Male and female groups were handled separately as a statistically significant difference was found between the sexes in the original studies. A test sample of 30 individuals was used to determine if this approach could be used with confidence in estimating age of living individuals. The outcomes obtained from the test sample indicated a close correlation between the actual ages (in years and months) and the predicted ages (in years only), demonstrating an average age difference of 0.47 years between the corresponding values. This method showed that the application of decision tree analysis using the combination of third molar and cervical vertebral development is usable and potentially valuable in this application.

Phototherapy for atopic dermatitis: A survey of European practice.

BACKGROUND: Phototherapy is used to treat atopic dermatitis (AD). Evidence for its efficacy, impact on quality of life, cost-effectiveness and short- and long-term safety with real-life usage is weak. OBJECTIVES: We established a taskforce to examine how phototherapy is currently being used as a treatment for AD across the United Kingdom and Europe to inform our understanding and guide future research into management of patients with AD using UV-based phototherapies. METHODS: An anonymous electronic multiple-response survey exploring phototherapy prescribing practices and experience of phototherapy modalities was developed by the study authors and sent to members of phototherapy networks from the United Kingdom and Europe. Responses were received between February and July 2021. RESULTS: About 144 respondents from 27 European countries completed the survey. NBUVB was the most widely used [n = 138 (96%)]. Home-based NBUVB was available in 8/27 countries (25/144 respondents, 17%). Oral psoralen-UVA (PUVA) was more widely available than bath PUVA (n = 106, 74% vs. n = 60, 42%) and used mainly in adult patients. 49/144 (34%) of respondents had access to UVA1. Phototherapy would be considered instead of systemic treatment in 96% of adults and 82% of children for NBUVB, versus 40% of adults and 3% of children for PUVA. Starting doses, standard dosing increments, length of treatment courses, lifetime limits for treatments and thresholds for performing annual skin assessments varied between responders. CONCLUSIONS: NBUVB was the most widely used phototherapy for AD in adult and paediatric patients, while PUVA and UVA1 were less used. Prescribing practices varied considerably, highlighting the lack of consensus practice in many different aspects of phototherapy for the treatment of AD in children and adults. This indicates that further studies are required to determine optimal phototherapeutic regimens for AD and informs our understanding of parameters that should be included in future high-quality randomized controlled trials (RCT) of phototherapy.

Inter-population variation of histomorphometric variables used in the estimation of age-at-death.

Population variation of several microscopic structures used in age-at-death estimation was assessed for three different population samples. The aim of the study was to determine if the need exists for population-specific standards when dealing with individuals of African and European origin. A total sample 223 bone sections from the anterior cortex of the femur (n = 99 black South Africans, n = 94 white South Africans and n = 30 Danish individuals) were analysed using a stereological protocol. Variables assessed included the average number of osteons per grid area (OPD), osteon size and Haversian canal size. ANCOVA was employed for assessment of statistically significant differences. The results indicated that OPD differed significantly between the three groups, but that osteon size was similar for all individuals. Haversian canal size showed unpredictable changes with age and high levels of variation, making it unsuitable to use for age estimation as a single factor. As there are conflicting opinions in the literature on whether to use population-specific equations for the estimation of age-at-death or not, this paper provided additional insight into the use of specific variables and its related variation between groups.

Histological age-at-death estimation in white South Africans using stereology.

Various methods are available for estimating age from skeletal remains, amongst them the use of histomorphometry. It is generally argued that age estimation standards are population specific, but this in itself creates problems as the reference samples used are often not large enough and/or lack substantial representation of all age cohorts. Traditional age methods have been shown to suffer from problems such as age mimicry. This paper aims at establishing histological age-at-death standards for the white South African population by supplementing the available sample (lacking an adequate number of young adults) with another sample of European descent to avoid over-estimation of age in younger individuals caused by age mimicry. Bone microstructures related to the number of osteons and fragments, osteon size and Haversian canal size that change with advancing age were used for the development of regression formulae. A histomorphometric assessment of the anterior cortex of the femur was done using stereology for the estimation of age at death. All sections were analysed using the optical fractionator and nucleator probes. A sample of 94 bone sections (n = 50 male, n = 44 females) of white South African individuals were used. A sample of Danish individuals (n = 14 males, n = 16 females) was combined with the South African sample to create a normal age distribution for the reference sample. Single and multiple regression equations were developed after randomly selecting a hold-out sample (n = 14) for validation. Osteon size (average length, surface area and volume) showed the highest correlation with age, followed by the number of osteons and fragments per grid area. Haversian canal size showed inconsistent changes with advancing age. Using the regression equations, predicted ages were obtained for the 14 individuals. RMSE values ranged between 14 and 17 years, which we deemed acceptable.

Age estimation from anterior cervical vertebral ring apophysis ossification in South Africans.

Age estimation in living individuals around the age of 18 years remains a difficult challenge. In this study, the anterior inferior vertebral ring apophysis development of cervical vertebrae C2, C3, and C4 of 496 white and 478 black South African individuals aged between 15 and 22 years was assessed from cephalometric radiographs. Apophysis development was scored according to a four-stage scoring system. Ancestry and sex differences in apophysis maturation were assessed and likelihood values determined for individuals in each population group being 18 years, based on developmental stages. Regression equations were developed for each ancestry and sex group. The results indicated that the median ages for attainment of stages 0, 1, and 2 were below the 18-year threshold for all ancestry and sex groups. Additionally, WSA males and BSA females attained stage 3 for C2, and WSA females attained stage 3 for C2, C3, and C4, below the 18-year threshold. The presence of stage 0 for black and white males in all three observed vertebrae and stage 1 for black males for C2, C3, and C4, white females for C2 and C3, and white males for C4 indicates an age below 18 years (with a 95% or higher probability). The results indicate that anterior inferior apophysis ossification stages of C2, C3, and C4 can be used as a reliable indicator to determine the likelihood of being 18 years of age at a 95% confidence index level. Apophysis development provides a valuable addition to the methods that can be used to assess age in the adolescent years.

Treated acid mine drainage and stream recovery: Downstream impacts on benthic macroinvertebrate communities in relation to multispecies toxicity bioassays.

The success and long term effectiveness of extensive and expensive engineering solutions to restore streams impacted by Acid Mine Drainage (AMD) is rarely tested. Concentrations of pollutants were measured in water along a longitudinal gradient from a stretch of the Tweelopie stream, South Africa, that receives pH-treated acid mine drainage (AMD) from an abandoned gold mine. The biotoxic effects of treated AMD were determined through macroinvertebrate biotic indices (SASS5) and a battery of toxicity bioassays. These included the L. sativa, A. cepa, D. magna toxicity and Ames mutagenicity tests, as well as an in vitro human liver cancer cell line HepG2. Even though the Tweelopie stream was moderately to severely degraded by multiple anthropogenic stressors, the impact of the treated AMD was masked by the improvement in the system downstream after mixing with the domestic wastewater effluent receiving stream, and subsequent further dilution as a result of the karst springs downstream. The general improvement of the system downstream was clearly shown by the decrease in the ecotoxicity and mutagenicity in relation to the in-stream macroinvertebrates. PCA multivariate analysis successfully displayed associations between the different environmental variables and the decrease in toxicity and subsequent ecosystem improvement downstream. This study indicated that environmental management of AMD remediation should consider long term assessment strategies, including multiple factors, to promote biological ecosystem recovery.

A comparison between decomposition rates of buried and surface remains in a temperate region of South Africa.

Several studies have been conducted on decomposition patterns and rates of surface remains; however, much less are known about this process for buried remains. Understanding the process of decomposition in buried remains is extremely important and aids in criminal investigations, especially when attempting to estimate the post mortem interval (PMI). The aim of this study was to compare the rates of decomposition between buried and surface remains. For this purpose, 25 pigs (Sus scrofa; 45-80 kg) were buried and excavated at different post mortem intervals (7, 14, 33, 92, and 183 days). The observed total body scores were then compared to those of surface remains decomposing at the same location. Stages of decomposition were scored according to separate categories for different anatomical regions based on standardised methods. Variation in the degree of decomposition was considerable especially with the buried 7-day interval pigs that displayed different degrees of discolouration in the lower abdomen and trunk. At 14 and 33 days, buried pigs displayed features commonly associated with the early stages of decomposition, but with less variation. A state of advanced decomposition was reached where little change was observed in the next ±90-183 days after interment. Although the patterns of decomposition for buried and surface remains were very similar, the rates differed considerably. Based on the observations made in this study, guidelines for the estimation of PMI are proposed. This pertains to buried remains found at a depth of approximately 0.75 m in the Central Highveld of South Africa.

Estimating age and the probability of being at least 18 years of age using third molars: a comparison between Black and White individuals living in South Africa.

Third molar development of 705 White and 563 Black South African individuals aged between 15 and 25 years was assessed from panoramic radiographs obtained from the School of Dentistry, University of Pretoria, South Africa. The maxillary and mandibular left third molars were scored according to a ten-stage scoring system. Ancestry and sex differences in dental maturity were assessed, and the likelihood of an individual being 18 years of age was determined for each developmental stage. Statistically significant differences were noted among ancestry groups for most developmental stages, with South African Black individuals consistently maturing earlier than the White individuals. Statistically significant differences were noted among sex groups for some of the stages, mostly those near the final stages of root development. The results indicate that male third molars completed their development faster than that of females. The likelihood of an individual being 18 years of age based on the third molar development stage for the maxilla and mandible on its own was also determined. Combined likelihood results, for the maxillary and mandibular left third molars for stage H, increased the likelihood of being 18 years to 95% for all the studied ancestry and sex groups.

Comparison of fixed and mobile-bearing total knee arthroplasty in terms of patellofemoral pain and function: a prospective, randomised, controlled trial.

BACKGROUND: Despite growing evidence in the literature, there is still a lack of consensus regarding the use of the mobile-bearing (MB) design total knee arthroplasty (TKA). METHODS: In a prospective, comparative, randomised, single centre trial, 106 patients with end-stage osteoarthritis of the knee were randomised to either an MB or fixed-bearing (FB) group to receive posterior stabilised (PS)-TKA using a standard medial parapatellar approach and patellar resurfacing with follow-up (FU) for 5 years. The primary outcome was anterior knee pain (AKP) during the chair rise test and the stair climb test 5 years after surgery. The secondary outcome was the ability to rise from a chair and to climb stairs, range of motion (ROM), Knee Society Score (KSS), RAND-36 scores and radiological analysis of the patellar tilt. RESULTS: No statistically significant difference was found between the two groups at 5 years FU in terms of median AKP during the chair rise test and the stair climb test (p = 0.5 and p = 0.8, respectively). There was no significant difference in any of the other secondary outcome parameters between the groups at 5 years FU. CONCLUSION: A mobile-bearing TKA does not decrease AKP compared to fixed bearings. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT02892838 . LEVEL OF EVIDENCE: II.

Age estimation from the acetabulum in South African black males.

Anthropologists are constantly seeking to improve methods for age estimation in the human skeleton. A new method was introduced about a decade ago that assesses the morphological changes that take place in the acetabulum as an individual ages. The pelvis is usually well preserved in forensic cases, which makes this method potentially valuable as an adult age indicator. This method employs seven variables, each with its own set of phases. To test the accuracy and reliability of this method, 100 black South African male acetabula from the Pretoria Bone Collection were assessed based on the criteria described in the original study. Box plots and transition curves were constructed to establish whether progression with age was visible and how it could possibly be modelled. Inter-observer reliability was also assessed by making use of Fleiss's Kappa statistic. Five specimens were used as out-of-sample examples for which maximum likelihood (point) estimates were calculated. The results demonstrated that middle and older individuals' age estimates were vastly underestimated. Inter-observer repeatability was poor, which suggested that the classification system most likely needs to be modified. A discussion and recommendation is given for improvement of reliability and repeatability of this method.

Violence against children: A review of cases at a forensic anthropology unit, Johannesburg, South Africa.

South Africa is experiencing a scourge of violence against women and children, with alarming levels of violence, and as such, juvenile cases are sometimes encountered in a forensic anthropological setting. The aim of this research was to assess the cases of juveniles (under 20 years) presenting at the Human Variation and Identification Research Unit (HVIRU) for a 6-year period (2016-2022), in order to assess patterns and types of cases referred. A total of 19 cases were assessed, of which 10 were 16-20 years old, 3 between the ages of 5 and 15 years and 6 less than 5 years old at the time of death. Of the 14 children with known sex, 12 were female with features suggesting that they fell prey to sexual violence. Many of the individuals were either known (and referred for trauma analysis) or identified following investigation. Of the 19 juveniles, 11 (58 %) had evidence of perimortem trauma (sharp and/or blunt), attesting to the violent nature of their deaths. Two cases had both sharp and blunt force trauma, of which one is a possible case of dismemberment. The remains of two individuals showed signs of perimortem burning, which may or may not be related to the cause of death. Three individuals had signs of antemortem (healed) trauma, which may suggest a longer period of abuse. Five of the individuals showed signs of disease - two had cribra orbitalia, while two others had various porous lesions indicative of chronic disease or malnutrition. One individual had advanced osteomyelitis, suggesting a natural cause of death. Some of these cases had unusual trauma and pathology, highlighting the contribution of forensic anthropologists.

Diffuse Idiopathic Skeletal Hyperostosis (DISH): New evidence from micro-XCT scanning.

OBJECTIVE: To observe and describe the development and underlying structure of the spinal manifestations of individuals osteologically diagnosed with DISH (Diffuse Idiopathic Skeletal Hyperostosis), using micro-XCT imaging. MATERIALS: A total of 72 individuals with DISH were identified in two modern skeletal collections in South Africa. METHODS: Vertebral columns affected by DISH were scanned at the micro-focus x-ray computed tomography facility at the Nuclear Energy Corporation of South Africa. Four features were macroscopically examined: (1) the origin of the new bone growth; (2) retention of the original vertebral cortex at the site of the new bone formation associated with DISH; (3) evidence of trabecular bone with or without sclerosis on the anterolateral surface of affected vertebrae; and (4) abnormal areas of osteosclerosis beyond features associated with DISH. RESULTS: Considerable variation across and between the four recorded features was found. Of note, 81% (n = 58) of individuals had both developed trabecular bone within the flowing new bone formation (feature 3), without retention of the original vertebral cortex (feature 2). CONCLUSIONS: Possible localised erosive/inflammatory processes destroyed the original cortex of the vertebral body and resulted in the expansion of trabeculae with new bone formation. SIGNIFICANCE: Micro-XCT imaging shed new light on the development of DISH, adding to literature suggesting that it could be an inflammatory disease. LIMITATIONS: Clinical histories of the individuals were not known. SUGGESTIONS FOR FURTHER RESEARCH: The role of chronic inflammatory disease in the development of DISH should be further explored including both the extra-spinal and spinal manifestations.

Effects of preharvest treatment, disinfections, packaging and storage environment on quality of tomato.

The major objective of this study was to explore the significance of an integrated agro technology in maintenance of postharvest quality of tomato. Preharvest ComCat® treated tomatoes and untreated controls were evaluated for changes in physiological, chemical, and microbiological quality during storage at 13 °C and room temperature (16.9-25.2 °C) and a relative humidity of 34-76%. Effects of disinfection coupled with packaging were evaluated. Physiological weight loss, total soluble solids, peroxidase activity and marketability were maintained better in anolyte disinfected tomatoes. At harvest, ComCat® treated tomatoes had lower pH, glucose and microbial populations, and higher total soluble solids, total titratable acids, sucrose, peroxidase activity than controls. The total soluble solids were better retained in ComCat® treated tomatoes than in control, while the sucrose and glucose contents remained lower after ripening. Peroxidase activities were lower in ripening ComCat® treated tomatoes, and difference in polygalactronase activity was only visible after 30 days. The microbial populations were lower in ComCat® treated fruit. Marketability of ComCat® treated tomatoes was better than that of the control. Integrated technology covering preharvest ComCat® application, disinfection with anolyte water and packaging combined with cold storage at 13 °C maintained the superior quality of tomato.

The use of decision tree analysis for improving age estimation standards from the acetabulum.

Accurate, reliable and easy-to-use statistical methods in multifactorial age estimation from the skeleton remains a much-debated issue. In this paper, we explore the use of decision trees in adult age estimation. For this purpose, a dataset from 100 acetabula of South Africans, previously used for age estimation using transition analysis, were used to build a basic decision tree. A test sample of 25 individuals were then employed to assess the newly developed decision tree. Using the decision tree, 20 of the 25 individuals were classified into the correct age group (young, middle or older adults), with the remaining 5 falling within the adjacent age group. The decision tree provided a more accurate outcome as compared to the previous study using transition analysis. Although much research is still needed, this analysis suggests that decision trees may be usable in adult age estimation and may handle the non-linear relationship between chronological and biological age somewhat better than other traditional statistical methods.

Infectious disease and nutritional deficiencies in early industrialized South Africa.

OBJECTIVE: Real industrialization was late to arrive in South Africa and was associated with the development of mining in its northern regions. This paper explores the development and spread of infectious diseases (particularly tuberculosis), against the backdrop of metabolic disease. MATERIALS: Published data regarding skeletons from various mining sites and historical information are collated, including information from the early accessions into the Raymond A. Dart Collection. METHODS: While findings from several sites (e.g., Gladstone at Kimberley, Koffiefontein, Witwatersrand Deep Mine and Lancaster Mine) have been described individually, they have not been assessed collectively. This paper provides a broad overview by collating information from these sites, in comparison with a rural, pre-industrialized population. RESULTS: Malnutrition, including scurvy, was common in most mining groups. Tuberculosis was rare in earlier mining groups, and the first possible skeletal cases only occurred after the establishment of closed housing compounds. From there it spread rapidly across the subcontinent. CONCLUSIONS: Nutritional insufficiencies / metabolic disease and high death rates, due to trauma and infectious diseases, were common. Tuberculosis in South Africa is closely associated with development of the mining industry. SIGNIFICANCE: This research highlights the development of tuberculosis in South Africa and its association with the mining industry. The role of migrant labor and the associated housing practices is elucidated. LIMITATIONS: Sample sizes are limited, but the findings of this study are supported by documentary evidence. FUTURE RESEARCH: Sample sizes should be increased, and the association between closed compound living and the development of disease further explored.

An evaluation of the Acsádi and Nemeskéri Complex Method of adult age estimation in a modern South African skeletal sample.

The Acsádi and Nemeskéri Complex Method is a multifactorial adult age estimation method that makes use of weighting systems. The Complex Method employs the use of four skeletal elements in assessing age, including the degree of endocranial suture closure, age-related changes to the pubic symphyseal surface, and the internal structural changes observable in the proximal humerus and femur. Acsádi and Nemeskéri reported a very optimistic error margin of ±2.5 years when all four skeletal elements were used. Despite these promising results, the Complex Method's effectiveness has been questioned, suggesting that it results in a constant over- and underestimation of age in younger and older groups, respectively. In this study, the Complex Method was tested on a modern South African skeletal sample (n = 313) with individuals of known age-at-death. Results from this study to some extent justify the critique levelled against the Complex Method's tendency to over- and underestimate age. Nevertheless, the Complex Method still performed surprisingly well for certain skeletal element combinations. Contrary to Acsádi and Nemeskéri's findings, the use of all four skeletal elements did not provide more accurate age estimates. For the most part, combinations making use of three or two skeletal elements outperformed the use of all four skeletal indicators. Results from this study indicate caution in using a blanket approach when it comes to deciding on the best combination of skeletal elements used in multifactorial methods. It is suggested that the Complex Method may be optimised by making use of sex- and population-specific skeletal element combinations and weighting systems in the future.

Derepression of glomerular filtration, renal blood flow and antioxidant defence in patients with type 2 diabetes at high-risk of cardiorenal disease.

BACKGROUND: The role of antioxidant status on microvascular blood flow and glomerular filtration (eGFR) in patients with type 2 diabetes and hypertension whose risk of progressive renal disease varies by ethnicity is unknown. METHODS: Adult, non-Caucasian (n = 101) and Caucasian (n = 69) patients with type 2 diabetes, hypertension and/or microalbuminuria and an eGFR > 45 mL/min/1.73 m2 were randomised to receive 400 IU vitamin E and/or 20 µg selenium daily or matching placebo. eGFR (CKD-EPI) was measured at baseline, 3,6 and 12 months and renal blood flow by contrast-enhanced ultrasonography in a sub-group (n = 9) at baseline and 3 months by assessing the area under the time intensity curve (TIC). Circulating glutathione peroxidase 3 (GPx-3) activity was measured as a biomarker of oxidative defence status. RESULTS: The time to change in eGFR was shortest with combined vitamin E and selenium than usual care (5.6 [4.0-7.0] vs 8.9 [6.8-10.9 months]; p = 0.006). Area under the TIC was reduced compared to baseline (38.52 [22.41-90.49] vs 123 [86.98-367.03]dB.s; P ≤ 0.05 and 347 [175.88-654.92] vs 928.03 [448.45-1683]dB.s; P ≤ 0.05, respectively] at 3 months suggesting an increase in rate of perfusion. The proportional change in eGFR at 12 months was greater in the group whose GPx-3 activity was above, compared with those below the cohort median (360 U/L) in the non-Caucasian and the Caucasian groups (19.1(12.5-25.7] % vs 6.5[-3.5 to 16.5] % and 12.8 [0.7 to 24] % vs 0.2 [-6.1 to 6.5] %). CONCLUSION: In these patients with type 2 diabetes and early CKD, antioxidant treatment derepresses renal blood flow and a rise in eGFR correlated directly with GPx-3 activity. SIGNIFICANCE: Diabetes mellitus is the world's leading cause of end-stage renal disease which has a predilection for black and minor ethnic groups compared with Caucasians. The differences in risk despite the benefits of conventional care may be related to oxidative stress. We found that glomerular filtration and renal blood flow is suppressed when renal function is preserved in high-risk patients with type 2 diabetes. Conventional care supplemented with selenium - the co-factor for glutathione peroxidase-3 (GPx-3) - improves renal perfusion and increase glomerular filtration according to host antioxidant defence determined by GPx-3 activity. Circulating GPx-3 activity warrants further investigation as a novel biomarker of reversible haemodynamic changes in early diabetic kidney disease to better enable targeting of renoprotective strategies.

A report on the high incidence of supernumerary teeth in skeletal remains from a 19th century mining community from Kimberley, South Africa.

INTRODUCTION: Supernumerary teeth can be described as the presence of more than 20 deciduous, or 32 permanent teeth in one individual. This condition occurs in 0.1% - 3.7% of individuals within most populations. AIM: The purpose of this study was to examine the incidence of hyperdontia in a 19th century mining community from Kimberley. MATERIALS AND METHODS: The Sol Plaatjie municipality disturbed several unmarked graves outside the fenced Gladstone cemetery in Kimberley, South Africa. The remains belonged to mine workers and other individuals who died in the Kimberley and surrounding hospitals between 1897 and 1900. The well preserved teeth of 76 adult males and 13 adult females were examined and counted. RESULTS: Supernumerary teeth were documented in 6.7% (N = 6) of the study population. This was high when considering the incidence of this condition in other population groups. Two of the seven individuals affected by the condition presented with multiple non-syndromal supernumerary teeth. CONCLUSION: The Gladstone sample population was mostly composed of migrant workers, and it is proposed that, although several factors may influence the development of supernumerary teeth, the possibility of a genetic relationship between some of these individuals should be considered to be responsible for the high incidence of hyperdontia in this sample.

Age estimation using bone mineral density in South Africans.

The use of bone mineral density (BMD) to predict age-at-death in skeletal remains provides a usable alternative to other methods because the values obtained are not observer-dependent. The aim of this study was to investigate the usability of BMD to estimate age in South African populations, and to assess inter-population variation and sex-specific differences in BMD values from the proximal end of the femur. In order to estimate age, regression analysis was done for the construction of population dependent formulae. The sample comprised of a total of 123 femora of black and white South Africans. DXA scans were performed using the Hologic Discovery system. Data analysis was done by employing independent-samples t-tests and correlation/regression analyses. The results indicated a statistically significant difference between black and white South Africans. Male groups were also significantly different from one another, but black and white females showed no significant differences. Linear regression analysis revealed a significant correlation between BMD values and age for the white population and the combined sample, but not for the black population. Bootstrapping were employed to confirm validity of the results. In conclusion, this study showed that the use of DXA measurements of the femur for estimating age may be used for the estimation of age-at-death in white South Africans, but more research is needed to better understand the relationship between bone mineral density and age in black South Africans.

Life expectancy of the 20th century Venda: a compilation of skeletal and cemetery data.

Little information is available on the 20th century mortality rates of rural black South African groups, such as the Venda. The purpose of this study was to apply abridged life tables in order to estimate life expectancy from both skeletal remains and death registry information of modern South African communities. Comparisons were also made with prehistoric and contemporary groups as a means to better evaluate life expectancy for this time period. The sample consisted of 160 skeletons of known Venda origin and burial registry information for 1364 black South Africans from the Rebecca Street and Mamelodi Cemeteries in Pretoria, South Africa. Standard anthropological techniques were applied to determine sex and estimate age from the skeletal remains. The stationary and non-stationary life table models were used to analyse the data. A high rate of child mortality, low juvenile and adult mortality with a steady increase in mortality after the age of 30 years was observed for both the Venda and the cemetery samples. Throughout the 20th century, life expectancy was shown to increase for black South Africans. However, due to the widespread HIV infection/AIDS of the 21st century, infant and young adult mortality rates continue to rise at such a speed that the decline in mortality seen for South Africans in the last 50 years will most likely to be lost in the next decade due to this disease.