Establishing an accurate diagnosis is crucial in everyday clinical practice. It forms the starting point for clinical decision-making, for instance regarding treatment options or further testing. In this context, clinicians have to deal with probabilities (instead of certainties) that are often hard to quantify. During the diagnostic process, clinicians move from the probability of disease before testing (prior or pretest probability) to the probability of disease after testing (posterior or posttest probability) based on the results of one or more diagnostic tests. This reasoning in probabilities is reflected by a statistical theorem that has an important application in diagnosis Bayes' rule. A basic understanding of the use of Bayes' rule in diagnosis is pivotal for clinicians. This rule shows how both the prior probability (also called prevalence) and the measurement properties of diagnostic tests (sensitivity and specificity) are crucial determinants of the posterior probability of disease (predictive value), on the basis of which clinical decisions are made. This article provides a simple explanation of the interpretation and use of Bayes' rule in diagnosis.Minamata disease or methyl mercury poisoning from industrial pollution was first described from Minamata, Japan in the 1950s. Subsequently, a similar poisoning episode occurred at Niigata, Japan in the 1960s. This paper describes the Minamata event and then presents two case reports believed to be prenatal poisoning from consumption of contaminated fish at Niigata. Case number one is of special interest because it is the only subject with congenital Minamata disease for whom exposure was actually measured near the time of birth.Methyl mercury (MeHg) is a neurotoxicant that with sufficient exposure can seriously impair the central nervous system and cause mental retardation, cerebral palsy, and neuromotor dysfunction. The level of exposure needed to adversely affect the nervous system is unknown. Human exposure to low levels of MeHg is common from consumption of fish. We examined the relationship between MeHg exposure and development of articulatory-phonologic speech skills in children whose mothers consumed a diet high in fish during pregnancy to determine whether any adverse associations could be detected. A total of 544 children from the Republic of Seychelles were given a speech assessment when they were 66 months of age. Exposure level was determined by measuring MeHg in maternal hair growing during pregnancy. No adverse associations between articulatory- phonologic speech skills and prenatal MeHg exposure were detected. The findings of this investigation are compatible with previous developmental assessments of Seychellois children that have indicated no adverse effects of prenatal MeHg exposure from fish consumption.Recent development in measuring educational outcomes has led to increased collaboration between international organisations and better understanding of education systems. From SACMEQ (Southern and Eastern Africa Consortium for Monitoring Educational Quality) a full data archive of the achievement of Grade 6 pupils in fourteen developing countries (including Seychelles) has been prepared. At the same time, from the Seychelles Child Development Study (SCDS) a longitudinal information system has been built on a cohort of Seychellois children from early childhood through their primary education. read more In this paper, the two sets of data are used to increase understanding of the achievement of pupils in primary schools in Seychelles. The cross-national comparisons of the achievement of pupils in two key learning areas, reading and mathematics, have been discussed to highlight the relative performance of Grade 6 (P6) in the SACMEQ school systems. In addition, the literacy and numeracy levels of Grade 6 pupils have been analysed to bring into sharper focus the Seychelles primary school system. By linking educational outcome at the end of primary schooling and child development outcomes during the primary education cycle, it has been possible to confirm some of the findings from the SACMEQ study. Moreover factors with potential to influence the performance of pupils and affect the learning process in the primary education system in Seychelles have been tentatively explored.Epidemiological studies to determine the impact of low level toxic exposure on child development are important in guiding clinical and public health action. However, carrying out such studies and interpreting their findings presents a number of significant challenges to the investigators. First, they must find a cohort with suitable exposure, select a biomarker that will accurately determine the level of exposure and determine the endpoints that are most likely to detect subtle differences in neurodevelopment. Following that, the logistics of the study must be organised and collaboration established with the local population and health authorities. To accurately interpret the data, they must also accurately determine covariates that impact child development. After the data are collected, interpreting the findings presents a further challenge. Throughout this process, the study must adhere to fundamental epidemiological principles and clearly defined statistical approaches. This paper discusses those principles and uses the Seychelles Child Development Study to show how one epidemiological study addressed them.This review examines the role of nutrients in child development and outlines the key nutrients identified as potentially important to neurodevelopment among high fish consumers in the Seychelles Child Development Nutrition Study (SCDNS). It describes the clinical assessment of these nutrients in the blood and breast milk samples collected from the cohort of 300 pregnant women who were recruited, at their first antenatal visit, on the SCDNS. These key nutrients include the long chain polyunsaturated fatty acids (LCPUFA), docosohexaenoic acid (DHA) and arachidonic acid (AA), both of which may affect neurodevelopment in the later stages of fetal growth. Only DHA, however, is strongly associated with fish consumption, the predominant source of the neurotoxicant methyl mercury (MeHg). Any benefits of increased selenium status on neurodevelopment are likely to accrue via detoxification of MeHg during fetal growth, while benefits of optimal iodine or thyroid status are likely to be directly related to neurodevelopment during late fetal growth.read more
For further actions, you may consider blocking this person and/or reporting abuse
Top comments (0)