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Background: Making inferences about measles distribution patterns at small area level is vital for more focal targeted intervention. However, in statistical literature, the analysis of originally collected data on one resolution with the purpose to make inferences on a different level of spatial resolution is referred to as the misalignment problem. In Namibia the measles data were available in aggregated format at regional level for the period 2005 to 2014. This leads to a spatial misalignment problem if the purpose is to make decisions at constituency level. Moreover, although data on risk covariates of measles could be obtained at constituency level, they were not available each year between 2005 and 2014. Thus, assuming that covariates were constant through the study period would induce measurement errors which might have effects on the analysis results. This paper presents a spatio-temporal model through a multi-step approach in order to deal with misalignment and measurement error. Methods: For the period 2005–2014, measles data from the Ministry of Health and Social Services (MoHSS) were analysed in two steps. First, a multi-step approach was applied to correct spatial misalignment in the data. Second, a classical measurement error model was fitted to account for measurement errors. The time effects were specified using a nonparametric formulation for the linear trend through first order random walk. An interaction between area and time was modelled through type I and type II interaction structures. Results: The study showed that there was high variation in measles risk across constituencies and as well as over the study period (2005–2014). Furthermore, the risk of measles was found to be associated with (i) the number of people aged between 0 and 24 years, (ii) the percentages of women aged 15–49 with an educational level more than secondary, (iii) the percentages of children age 12–23 months who received measles vaccine, (iv) the percentages of malnourished children under 5 years, and (vi) the measles cases for each previous year. Conclusion: The study showed some of the determinants of measles risk and revealed areas at high risk through disease mapping. Additionally, the study showed a non-linear temporal distribution of measles risk over the study period. Finally, it was shown that ignoring the measurement errors may yield misleading results. It was recommended that group and geographically targeted intervention, prevention and control strategies can be tailored on the basis these findings. [ABSTRACT FROM AUTHOR]

Reducing maternal mortality is a big challenge facing low-income nations. Some of the causes of maternal mortality have been studied, however, much less is known about differentials in pregnancy-related deaths among women of different age groups. This study used nationally representative data from demographic and health surveys (DHS) in Namibia, Kenya and Sierra Leone. A direct sisterhood method was used to estimate pregnancy-related deaths based on 7 years of recollection. Findings of the study reveal that death during the antenatal period was the commonest time of death in mothers aged 15-19, while death during delivery and two months after delivery were the leading causes of death for mothers aged 20-24. Pregnancy-related deaths were more prevalent among women with no schooling or primary education than their counterparts with secondary and higher education.Impact statementWhat is already known on this subject? Postpartum bleeding, malaria, anaemia, HIV/AIDS, unsafe abortion-related complications, obstructed labour, postpartum infections, high blood pressure during pregnancy and pre-existing conditions and cardiovascular disease are known causes of maternal mortality. However, much less is known about differentials in pregnancy-related deaths among women of different age groups.What do the results of this study add? Findings of the study revealed that death during pregnancy was the top pregnancy-related cause of death for mothers aged 15-19, while death during delivery and two months after delivery were the leading causes of death for mothers aged 20-24. Pregnancy-related deaths were more prevalent among women with no schooling or primary education than their counterparts with secondary and higher educationWhat are the implications of these findings for clinical practice and/or further research? By knowing where the risk is highest as well as where the numbers of deaths are greatest, it may be possible to re-direct resources and fine-tune strategies for greater effectiveness in efforts to reduce maternal mortality. [ABSTRACT FROM AUTHOR]

Namibia's most important commercial fisheries resource, the shallow-water Cape hake Merluccius capensis, is currently assessed using statistical catch-at-age analysis. Age data obtained from otoliths constitute an important data component of this model. Recent age-validation studies of M. capensis showed that growth was previously underestimated. We investigated this new fast-growth hypothesis (FGH) by using measurements and counts of translucent zones (T1 to T14, from otolith core to edge) on two survey otolith samples covering the entire range of fish lengths. We compared three hypotheses of periodicity of otolith zone formation and show that, if all zones are counted, T2 (at 9.0 mm otolith length), T5, T8, T11 and T14 are most likely to be annuli. A conversion from the slow-growth-hypothesis (SGH, currently used) age data was calculated as: FGH age group = round (0.41[SGH age group] + 0.25), and this formula should be applied to compute and test updated catch-at-age data in a future hake stock assessment. Additional adjustment for the hake stock assessment following the FGH, such as the timing of recruitment in winter and catches in summer, should be considered in future assessments. [ABSTRACT FROM AUTHOR]

Objective: Although the San in Namibia have been targeted by intensive development efforts, there is little knowledge available about San diet quality and nutritional status. The objective of this study is therefore to estimate and quantify the dietary diversity of a San group, and to investigate how socioeconomic characteristics affect dietary diversity. The dietary data (n = 200) for this cross-sectional study were collected as a part of a larger doctoral research investigating food environment, food choices, and dietary changes of the Khwe San in Bwabwata National Park East. Results: The mean dietary diversity score (DDS) of the participants was 2.44 out of 10, with only two people having a DDS of 5. 87.5% of participants consumed only from 2 or 3 different food groups, mainly grains/roots and dark green leafy vegetables. DDS significantly correlated only with the level of education and with age. Due to their collinearity, the group with no education had the lowest DDS, but also belonged to the oldest age group. The overall dietary diversity of the Khwe is extremely low, indicating severe nutritional inadequacy. The small differences in DDS among the socioeconomic groups indicate the importance of other determining factors, such as cultural and food environmental characteristics. [ABSTRACT FROM AUTHOR]