Sexing the cranium from the foramen magnum using discriminant analysis in a brazilian sample

Abstract In the identification process, the foramen magnum has shown controversial results in sex estimation. The present study aimed to analyze the morphometric variables of the foramen magnum in Brazilian adult cranium for sex estimation. The sample was composed of 100 craniums (53 males and 47 females) from the documented collection of the Institute of Teaching and Research in Forensic Sciences. The protocol measurement was constituted of two linear measurements: maximum length of the foramen magnum and maximum breadth of the foramen magnum and two formulas to calculate the area, method one (M1) and method two (M2). Descriptive statistics showed statistically significant differences between sex (p<0.05) for all variables. The univariate discriminant functions showed an accuracy between 56.0-62.0%, and the multivariate analysis showed a percentage of accuracy between 60.0-65.0%, the greatest accuracy was found combining the two linear measurements with M1(71.7%), even after cross-validation (66%). Receiver Operating Characteristic (ROC) curve analysis showed that M2 is the best parameter for estimating sex (AUC=0.693). A reference table for Brazilians using the foramen magnum parameters was developed based on the results of the ROC curve analysis. In conclusion, the foramen magnum should be used with caution to estimate sex in forensic cases of fragmentary craniums, due to the limited accuracy.

Resumo No processo de identificação humana, a análise do forame magno apresenta resultados controversos para estimativa do sexo. O presente estudo teve como objetivo analisar as variáveis morfométricas do forame magno em crânios adultos brasileiros para estimação sexual. A amostra foi composta por 100 crânios (53 sexos masculino e 47 sexo feminino) pertencentes a coleção osteológica documentada do Instituto de Ensino e Pesquisa em Ciências Forenses. A medida do protocolo foi constituída por duas medidas lineares: comprimento máximo do forame magno e largura máxima do forame magno e duas fórmulas para calcular a área, método um (M1) e método dois (M2). As estatísticas descritivas evidenciaram diferenças estatisticamente significativas (p<0,05) para todas as variáveis. As funções discriminantes univariadas apresentaram uma porcentagem de acerto entre 56,0-62,0% e a análise multivariada mostrou uma porcentagem de acerto entre 60,0-65,0%. A análise da curva ROC apontou que M2 é o melhor parâmetro para estimar o sexo (AUC=0,693). Uma tabela de referência para brasileiros que utilizam os parâmetros do forame magnum foi desenvolvida com base nos resultados da análise da curva ROC. Em conclusão, o foram e magnum deve ser usado com precaução para estimar o sexo em casos forenses de cranio fragmentado, devido à precisão limitada.

Craniometric variation among Brazilian and Scottish populations: a physical anthropology approach

Aim: The present investigation intended to compare the craniometric variations of two samples of different nationalities (Brazilian and Scottish). Materials and methods: The Brazilian sample consisted of 100 modern complete skulls, including 53 female skulls and 47 male skulls, and the Scottish sample consisted of 100 historical skulls (61 males, 39 females) and 36 mandibles (24 males, 12 females). The cranial measurement protocol was composed of 40 measurements, 11 bilateral and 29 unilateral, and the measurement protocol of the mandible was composed of 15 measurements, with six that were bilateral and nine that were unique. The comparative analysis of the metric variability between the two samples was performed using the means and medians analysis, the t-test, the Wilcoxon test, and the coefficient of variance, with a significance level of 5%. Results: The results showed that, among the 72 analysed variables, 44 measurements (61.11%) presented statistical differences between the samples. The Scottish skull tends to have a cranial length (GOL diff=5.53), breadth (XCB diff=3.78) and height (NPH diff=5.33) greater than the Brazilian skulls, and the Scottish mandibles tend to show a higher mandibular ramus height (MRH diff=9.25), a higher mandibular body height (HMB diff=6.37) and a larger bigonial breadth (BGB diff=5.29) than the Brazilians. The discriminant analysis of the 51 cranial measurements and 21 mandibular measurements showed a variation of the percentage of accuracy between 46.3-83.8%. Conclusion: The metric analysis demonstrated that there is variability between the two samples studied (61,11%), but a concrete cause cannot be determined considering the multifactorial aspects of the variations of form and size

Assessment of Implementation of an Anaemia Reduction Initiative Including Blanket Supplementary Feeding Distributing LNS and MNP on Anaemia in a Protracted Refugee Situation.

Objectives: Micronutrient malnutrition, commonly manifested as stunting and anaemia, is a persistent public health problems in populations experiencing a protracted refugee situation like the Western Sahara refugees living in south-west Algeria. A UNHCR and partners' strategy to address this issue was to implement a blanket supplementary feeding programme providing lipid-based nutrient supplements (LNS) and micronutrient powders (MNP) to children aged 6-35 and 36-59 months, respectively. We present data on anaemia prevalence in children aged 6-59 months after two-years of implementation. Methods: Routine pre- (2010) and post-intervention (2012) cross-sectional nutrition surveys were conducted assessing anaemia (Hb<11g/dL) in four Western Sahara refugee camps. Data on coverage was obtained by questionnaire in the post-intervention nutrition survey. Results: Overall, we observed a significant reduction in anaemia prevalence in children 6-59 months between baseline (52.8%; 95%CI: 49.1-56.6) and end-line (28.4%; 95% CI: 25.7-31.0); and an increase in mean haemoglobin concentration from 10.7 g/dL (s.d.:1.7) to 11.6 g/dL (s.d.:1.4). A similar pattern of differences for anaemia prevalence was observed when the analysis was stratified by camp. Coverage for LNS among children aged 6-35 months was 70%, contrasting with 14% for MNP among children aged 36-59 months.

Assessment of the Effectiveness of Nutributter® Distribution on Anaemia and Stunting in Refugee Populations in Djibouti and Kenya.

Objectives: Stunting and micronutrient malnutrition are persistent public health problems in refugee populations. UNHCR and partners use blanket supplementary feeding programmes (BSFP) using Nutributter®, a low-quantity lipid-based nutrient supplement, as one of the approaches to confront these problems. However, the evidence base for the efficacy and effectiveness of Nutributter® is limited. This secondary analysis aimed to assess the impact on anaemia and stunting in children 6-23 months and 6-59 months of a blanket Nutributter® distribution implemented in Dadaab, Kakuma, and Ali Addeh refugee camps. Methods: A plausibility design using routine pre- and post-intervention cross-sectional nutrition survey data was conducted. Trends in total anaemia (Hb<11g/dl), anaemia categories (mild, moderate and severe), and stunting (HAZ<2) between 2008-2011 were explored and interpreted using available contextual, and Nutributter® programme monitoring data. Results: In all camps, a significant reduction was seen in the prevalence of anaemia in children 6- 23 and 6-59 months between baseline and endline; percentage point reduction ranged from 9.3% to 23%, and 18.3% to 29.3% for each age group, respectively. Improvements were largely due to reductions in moderate and severe anaemia. The prevalence of stunting remained similar for children 6-59 and 6-23 showing little change after introduction of the intervention. Conclusions: The replicability of findings suggests that Nutributter® distribution is associated with a reduction in anaemia, especially in its most severe forms, among refugees in the Horn of Africa. These results need to be interpreted taking into account other anaemia reduction activities implemented in the camps between 2008 - 2011.

Anaemia in Pregnancy: Factors Associated with Maternal Anaemia in the Dadaab Refugee Camps, Kenya (2001-2002).

Objectives: 1) Describe the socioeconomic and health status of this population of pregnant women; 2) Determine the anaemia prevalence using a series of diagnostic markers (haemoglobin, sTFR, and ZPP); 3) Explore the relationship between a variety of socio-demographic, nutritional, and disease-related factors, and anaemia. Methods: This paper was developed using data collected during a longitudinal cohort study conducted between 2001-2002, which investigated the effectiveness of a new antenatal micronutrient supplement. A preliminary literature review identified known biological and socioeconomic risk factors associated with anaemia. Chi2, students t-test, correlation, and logistic regression analyses explored the strength of association between exposure variables and anaemia. Results: The prevalence of maternal anaemia in this population was 75% at 16-24 weeks gestation. Iron deficiency was similarly widespread; 65% and 45% of women exceeded the threshold for deficiency as defined by ZPP and sTFR indicators respectively. Malaria schistosomiasis, and hookworm infections were not significantly associated with anaemia in this population. MUAC and BMI were strongly correlated with anaemia, as was Somali ethnicity, iron deficiency (sTFR), and living in a rural context pre-displacement. Conclusions: The prevalence of anaemia and iron deficiency among pregnant women in Dadaab constituted a severe public health problem, as defined by the World Health Organisation. Since this study, a strategy for the control and reduction of anaemia has been developed by UNHCR and implemented in the Dadaab camps and elsewhere. However, data published more recently suggests that maternal anaemia remains a persistent problem (74%, 2005; 69%, 2008) that requires further attention and a continued response.