This study aimed to delineate temporal trends and differentials of completed fertility and their relationship with some characteristics of the marriage system in specific anthropological populations of northern Greece. The analysis was based on the life history of quinquennial and decennial birth cohorts of married women born in the 20th century who reproduced solely within the settlements studied. The variables studied were: children ever born, mean age of mother at first marriage, mean age of mother at first child (live birth), mean age of mother at last child and reproductive span. The results indicated that there were significant differences in the demographic characteristics of marriage and that there was an ongoing fertility transition in the 20th century in the populations studied. The mechanism of fertility decline was connected with the gradual reduction of the mean age of the mother at last child, the parallel decrease in the mean age at childbearing and a shortening of the reproductive span. Fertility levels at all times maintained a dynamic character imposed by local cultural, economic and social structures, which, in turn, were part of broader national and international structures, in all the populations studied. A strong trend of convergence of fertility levels was observed among the populations studied.

Age at sexual debut is known to have implications for future sexual behaviours and health outcomes, including HIV infection, early pregnancy and maternal mortality, but may also influence educational outcomes. Longitudinal data on schooling and sexual behaviour from a demographic surveillance site in Karonga district, northern Malawi, were analysed for 3153 respondents between the ages of 12 and 25 years to examine the association between sexual debut and primary school dropout, and the role of prior school performance. Time to dropout was modelled using the Fine and Gray survival model to account for the competing event of primary school completion. To deal with the time-varying nature of age at sexual debut and school performance, models were fitted using landmark analyses. Sexual debut was found to be associated with a five-fold increase in rate of subsequent dropout for girls and a two-fold increase in dropout rate for boys (adjusted hazard ratio [aHR] of 5.27, CI 4.22–6.57, and 2.19, CI 1.77–2.7, respectively). For girls who were sexually active by age 16, only 16% ultimately completed primary schooling, compared with 70% aged 18 or older at sexual debut. Prior to sexual debut, girls had primary completion levels similar to those of boys. The association between sexual debut and school dropout could not be explained by prior poor school performance: the effect of sexual debut on dropout was as strong among those who were not behind in school as among those who were overage for their school grade. Girls who were sexually active were more likely to repeat a grade, with no effect being seen for boys. Pathways to dropout are complex and may differ for boys and girls. Interventions are needed to improve school progression so children complete primary school before sexual debut, and to improve sex education and contraception provision.

This cross-sectional study analysed Bangladesh Demographic and Health Survey 2011 data with the aim of investigating the prevalence of, and risk factors for, hypertension in individuals aged over 35 by rural–urban place of residence. After estimation of the stratified prevalence of hypertension by background characteristics, multivariable logistic regression analysis was conducted to calculate the adjusted odds (AORs) and 95% confidence intervals (CIs) for selected factors. Of the 7839 participants, 1830 were from urban areas and 6009 from rural areas. The overall prevalence of hypertension was 32.6% (95% CI: 30.5–34.8) in urban areas and 23.6% (95% CI: 22.5–24.7) in rural areas. The prevalence and odds of hypertension increased with increasing age, female sex, concomitant diabetes and overweight/obesity and richer wealth status in both urban and rural regions. Although residence in Khulna and Rangpur divisions and higher education level were associated with increased odds of hypertension in urban regions, this was not the case in rural regions (p>0.05). Residence in Sylhet and Chittagong divisions had lower odds of hypertension in rural regions. Furthermore, the proportions of overweight/obese, diabetic and higher wealth status participants were higher in urban than in rural regions. The prevalence and odds of hypertension were found to be associated with several common factors after stratifying by place of residence. Some of these factors are more concentrated in urban regions, so urban residents with these risk factors need to be made more aware of these in order to control hypertension in Bangladesh. Public health programmes also need to be tailored differently for urban and rural regions, based on the different distribution of these significant factors in the two areas.

Te Nijenhuis et al. (2019) cite studies that show that training on cognitive tasks produces the largest standardized gains on the easiest items and the smallest standardized gains on the most difficult items. They note that this creates an anti-Jensen effect, and use this as a trump that is supposed to show that my basketball examples are irrelevant. I use a new basketball example that is compatible with those studies. It assumes that at some point improvement on the easy skills ‘stalls’ – and all that is left is some improvement on the hard skills. Therefore, further environmental enhancement means the higher level skill gap is increased, which gives a classic Jensen effect, which shows that the presence of such does not entail genetic causality. The difference is that we really can produce virtually optimum basketball skills while for cognition, we are still well short. I also address the problem of why IQ gains over time do not show an anti-g pattern. After all, they are environmentally caused, and ‘should’ do so if an anti-g pattern and environmental causes go together.

Bio-Detection Dogs (BDDs) are used in some high-income countries as a diagnostic intervention, yet little is known about their potential in low/middle-income countries with limited diagnostic resources. This exploratory study investigated the opportunities and implications of deploying BDDs as a mobile diagnostic intervention to identify people with asymptomatic malaria, particularly at ports of entry, as an important step to malaria elimination in a population. A qualitative study design consisting of participant observation, five focus group discussions and informal conversations was employed in The Gambia in April–May 2017. A disciplined German Shepherd companion dog (not trained as a BDD) was introduced to research participants and their perceptions recorded. Field-notes and discussions were transcribed, translated and analysed thematically. Most research participants viewed positively the possibility of using BDDs to detect malaria, with the major advantage of being non-invasive. Some concerns, however, were raised regarding safety and efficacy, as well as cultural issues around the place of dogs within human society. The Gambia is a rabies-endemic country, and unfamiliar dogs are not usually approached, with implications for how research participants perceived BDDs. Understanding such concerns and working with local people to address such issues must be part of any successful strategy to deploy BDDs in new settings. Bio-Detection Dogs represent a potentially non-invasive diagnostic tool for the detection of asymptomatic or chronic malaria infections, particularly in areas with very low parasite rates. However, it is important to understand local concerns and work closely with communities to address those concerns. Wider deployment of BDDs will also require careful planning and sustained financial support.

Most studies examining the association between female education and fertility have reported an inverse association. However, little is known about the consistency of the relationship, or what level of education triggers an inverse association. This study examined the consistency of the association between female education and fertility across the north–south demographic divide in Nigeria. Data on women aged 40–49 were taken from the 2003, 2008 and 2013 Nigerian DHS data sets. The results showed that female education remained significantly and consistently inversely related to fertility in both the north and south of Nigeria. Women with secondary or higher level of education reported a lower number of children ever born (CEB) than those with primary or no education in both the north and south (p<0.05). The findings suggest that female education has a more effective negative effect on fertility in the south, where the level of female schooling is higher, than in the north, with its limited level of female education. Primary-level female education appeared to be ineffective in reducing fertility in the study sample. Women with primary schooling reported a slightly higher CEB than those who did not have any formal education. Also, age at marriage and child mortality were found to be consistent and significant predictors of fertility in both the north and south (p<0.001). Women who married at relatively higher ages and those who had never lost a child reported a smaller CEB consistently in both the north and south (p<0.001). Therefore, to attain sustainable fertility decline throughout Nigeria, it is imperative that policies aimed at increasing the prevalence and quality of female education are pursued, and there must be a focus on social, physical, environmental and cultural factors influencing age at marriage and child mortality.

Worldwide data indicate a growing number of energy homeostasis disorders, which are especially dangerous in childhood. The distribution and growing trends of overweight and obesity in children have been widely investigated, unlike the prevalence of too-low body weight and its determinants. This study aimed to estimate the frequency of body mass deficiency in Polish rural girls and differences among four Polish regions – Choszczno and Leszno in the north-west, and Ostrów Mazowiecka and Suwałki in the north-east. Data were taken from 7764 rural girls aged 9–18 years examined in 1987, when the country was in economic crisis, and 9431 such girls examined in 2001, when the country was undergoing political transformation. The frequency of weight deficiency was estimated based on BMI by applying the international standards of Cole. An Extent of Overweight (EOW) index was used to create an Extent of Thinness (EOT) index. A significant increase in weight deficiency was found in the rural girls – from 7.5% in 1987 to 8.9% in 2001 – and an increase in the EOT index from 0.37 in 1987 to 0.43 in 2001. Analysis by area of residence demonstrated significant differentiation. In the regions in north-west Poland, mainly inhabited by non-farming families, the prevalence of weight deficiency in girls almost doubled from 1987 to 2001, probably because of the mass and long-term unemployment that resulted from the closure of state farms in 1992. In contrast, in the north-east regions, the prevalence of weight deficiency remained almost unchanged over this period, with only a slight decrease, probably because the inhabitants were mainly farm and farm/working families with better living conditions. Despite the overall increase in thinness prevalence in rural girls in Poland, different living conditions have had different biological effects.

Two administrations of the Coloured Progressive Matrices in Egypt were compared. The first was administered to a large, representative national sample between 2011 and 2013. The second was administered to primary school pupils in villages in Menoufia in northern Egypt in 2017. Adjusting for the Flynn Effect, the IQ of the rural northern Egyptians was shown to be statistically significantly higher than the national average. It is demonstrated that this is consistent with regional socioeconomic differences in Egypt, which strongly imply that northern Egypt has a higher average IQ than southern Egypt.

National Vector Borne Disease Control Programme (NVBDCP) data have shown that nearly half of all malaria deaths in India occur in tribal-dominated areas. The present study took a qualitative approach to understanding community perceptions and practices related to malarial infection and anti-malarial programmes. Twelve focus group discussions and 26 in-depth interviews of Accredited Social Health Activists (ASHAs) were conducted in nine villages in the district of Gadchiroli, Maharashtra state in India in June 2016. A total of 161 village residents (94 males and 67 females) participated in the focus group discussions and 26 health workers participated in the in-depth interviews. Data were analysed using the content analysis approach. The findings revealed widespread misconceptions about malaria among village residents, and low use of preventive measures and anti-malarial services. Ignorance and treatment by unqualified traditional healers delay effective treatment seeking. Furthermore, failure to maintain drug compliance adds to the gravity of the problem. The study identified the social and behavioural factors affecting treatment uptake and use of treatment facilities in the study area. These should help the development of the behavioural change communication arm of any control strategy for malaria through improving community participation, so improving preventive practices and optimizing utilization of anti-malarial services.

The aim of this study was to assess the knowledge of East Malaysian adolescents on sexual and reproductive health issues. Data were collected in March–July 2015 from 2858 adolescents aged 13–18 years from selected East Malaysian secondary schools using a self-administered questionnaire. Twelve items relating to sexual and reproductive health were used to measure respondents’ knowledge based on their responses ‘True’, ‘False’ or ‘Don’t know’, with the proportion of correct answers being the variable of interest. Cronbach’s alpha for the twelve items was 0.761 and the mean knowledge score was 6.8. While the majority of the respondents knew that a woman can get pregnant if she has sex with a man and that HIV and AIDS can be transmitted through sexual intercourse, knowledge about Malaysia’s abortion laws, that a woman can get pregnant if she has sex only once and that people with sexually transmitted infections may look healthy was poor. Older respondents and those from urban schools reported significantly higher knowledge than younger respondents and those from rural schools, respectively. More emphasis should be given in schools to the specific topics for which low levels of sexual and reproductive health knowledge were found, with greater attention being given to younger adolescents and those in rural areas.

This paper reports on the association between early marriage, age at first reproduction and height, as an indicator of childhood environment, and maternal health outcomes among traditional Roma women in Serbia. Demographic data, marital and reproductive histories, height, weight and self-rated health were collected from 414 Roma women living in rural settlements in Serbia in 2015–2017. Data analysis showed that higher age and weight were associated with a greater risk of poor health, greater height contributed to reduced risk of poor health while reproductive variables were insignificant. The study provides evidence that the long-term effects of early childbearing may not always be associated with poorer health status. As indicated by the differences in height, it is likely that women who were capable of reproducing very early on and staying healthy in later life were probably very healthy to begin with. The results probably reflect both the biological and social differences of early childhood. Aside from height, the traditional Roma marriage pattern and social benefits may have an additional protective effect on the health of women.

This study was based on data for a sample of 1756 Egyptian primary school children (863 boys and 893 girls) aged 5–11 years assessed for intelligence with Raven’s Coloured Progressive Matrices (CPM). The results showed that boys obtained a slightly higher IQ than girls and had greater variance.

India has gradually progressed into fertility transition over the last few decades. However, the timing and pace of this transition has varied notably in terms of both its geography and the demographic groups most affected by it. While much literature exists on the relationships between fertility level and its influence on demographic, economic, socio-cultural and policy-related factors, the potential spatial variations in the effects of these factors on the fertility level remain unaddressed. Using the most recent district-level census data (of 2011) for India, this nationwide study has identified plausible spatial dependencies and heterogeneities in the relationships between the district-wise Total Fertility Rates (TFRs) and their respective demographic, socioeconomic and cultural factors. After developing a geocoded database for 621 districts of India, spatial regression and Geographically Weighted Regression (GWR) models were used to decipher location-based relationships between the district-level TFR and its driving forces. The results revealed that the relationships between the district-level TFR and the considered selected predictors (percentage of Muslims, urbanization, caste group, female mean age at marriage, female education, females in the labour force, net migration, sex ratio at birth and exposure to mass media) were not spatially invariant in terms of their respective strength, magnitude and direction, and furthermore, these relationships were conspicuously place- and context-specific. This study suggests that such locality-based variations and their complexities cannot be explained simply by a single narrative of either socioeconomic advancement or government policy interventions. It therefore contributes to the ongoing debate on fertility research in India by highlighting the spatial dependence and heterogeneity of the impacts made by demographic, socioeconomic and cultural factors on local fertility levels. From a methodological perspective, the study also discerns that the GWR local model performs better, in terms of both model performance and prediction accuracy, compared with the conventional global model estimates.

A test of Jensen effects is of nil value as a diagnostic instrument when various good-sized meta-analyses show Jensen effects appear for both genetic effects and environmental effects. Using thought experiments, Flynn (2019) claims that some schooling gains yield Jensen effects, which should not be the case for an environmental effect. However, a meta-analysis (K = 12, total N = 60,993, mean r = 0.13) of schooling gains shows no Jensen effect. Real data trump thought experiments, so it is concluded there is no empirical proof of anomalous Jensen effects for schooling gains.

The aim of this study was to analyse the relationship between childhood socioeconomic conditions and body asymmetry in young Polish women. The study measured fluctuating asymmetry (FA), which refers to small random deviations from perfect symmetry in bilaterally paired body structures. Data were obtained from 620 female students aged from 19 to 25 years recruited from Jagiellonian University in Cracow, Poland. The research was carried out in the period from January 2016 to May 2017. A composite fluctuating asymmetry (cFA) of the women was calculated using five bilateral body traits. The lengths and widths of the women’s ears, lengths of their 2nd and 4th digits and wrist widths of the right and left sides of the body were measured twice using standard methodology. The following data were collected in a questionnaire: degree of urbanization of the woman’s place of residence during childhood, number of older siblings, parental education and woman’s dominant hand. The results showed a tendency for FA to fall with an increase in parental education, and to rise with an increase in number of older siblings. The level of FA was significantly lower in women from rural areas than in those from cities. The results of the study show that FA in early adulthood is significantly associated with socioeconomic status during childhood, and confirm that the level of FA in adulthood may be a good indicator of stress factors in the early stages of development.

Many factors influence the male:female birth ratio (number of male births divided by total births, M/T). Studies have suggested that this ratio may be positively correlated with the education levels of mothers. This study assessed the effect of maternal education on M/T in the US population overall and by racial group. Number of live births by sex of the child, maternal educational level reached and race were obtained from the Centres for Disease Control (CDC Wonder) for the period 2007–2015. The total study sample comprised 28,268,183 live births. Overall, for the four available recorded racial groups (Asian/Pacific Islander, White, American Indian/Alaska Native and Black/African American), M/T rose significantly with increasing education levels (p<0.0001). When analysed by race, this relationship was only found for White births (p<0.0001). The M/T of Black births rose with increasing maternal education level up to associate degree level (p=ns), then fell significantly with higher levels of education (χ2=4.5, p=0.03). No significant trends were present for Asian/Pacific Islander or American Indian/Alaska Native births. Socioeconomic indicators are generally indicators of better condition and in this study educational attainment was overall found to be positively correlated with M/T, supporting the Trivers–Willard hypothesis.

The objective of the study was to analyse selected anthropometric features of children, adolescents and young adults from middle-class families in Kolkata, India, by BMI and adiposity categories. Standardized anthropometric measurements of 4194 individuals (1999 male and 2195 female) aged 7–21 were carried out between the years 2005 and 2011. The results were compared by BMI and adiposity categories. Statistical significance was assessed using two-way-ANOVA and linear regression analysis was performed. The study population could be differentiated in terms of BMI and adiposity categories for all examined anthropometric characteristics (p ≤ 0.001). After taking age into consideration, differences were observed for males in the case of body height and humerus breadth in BMI and adiposity categories, and for femur breadth in the case of adiposity categories. For females, differences were noted in body height measurements in BMI and adiposity categories, a sum of skinfold thicknesses in BMI categories, and upper-arm and calf circumferences in adiposity categories. The patterns of differences in the BMI categories were found to be similar to those in adiposity categories. The linear regression analysis results showed that there was a significant relationship between BMI and body fat ratio in the examined population. Underweight individuals, and those with low adiposity, were characterized by lower extremity circumferences and skeletal breadths. These features reached highest values in overweight/obese persons, characterized by high body fat. However, the differences observed between each BMI and adiposity category, in most cases, were only present in early childhood.

The effects of educational training are only one case of producing two groups (before and after) separated by IQ test performance on easier and harder items. The crux of the issue is whether we know that the causes between groups are genetic if they are differentiated by a Jensen effect and that the causes are environmental if they are differentiated by an anti-Jensen effect. A Jensen effect occurs when the two groups differ more as cognitive tasks become more complex. It is shown that genes vs environment must be diagnosed on a case-by-case basis, not in terms of whether a Jensen effect is present.

The objective of this paper was to study nutritional status and growth, as measured by height and weight, over the life course and their connection with chronic diseases in Guatemala, a country with high levels of child undernutrition and adult overnutrition, using data from the Institute of Nutrition of Central America and Panama (INCAP) Nutrition Trial Cohort study. The study sample comprised a birth cohort of 1570 individuals who had data in the original 1969–1977 survey as well as the 2002–2004 follow-up, allowing for an analysis of the nutritional transition from childhood to adulthood. The associations between childhood and adulthood anthropometrics were analysed, and the links of these with chronic disease indicators were assessed using multiple regression analysis and structural equation modelling. Moving upwards in nutritional status from childhood to adulthood was observed frequently in the study population. Unlike sex and place of residence, early anthropometrics were not generally found to be associated with adult body mass index (BMI). However, direct relationships were found between childhood nutritional status and growth and adulthood high-density lipoprotein (HDL) cholesterol, triglycerides and fasting blood glucose. Furthermore, these relationships were not mediated by BMI. The findings were not sensitive to the metric of childhood anthropometrics, as the use of length-for-age, weight-for-age and weight-for-length all resulted in similar conclusions. These relationships demonstrate the importance of early childhood conditions for later-life outcomes. However, the lack of such relationships for blood pressure suggests that the biological links between childhood anthropometrics and various chronic diseases might vary.

Intelligence was assessed using the Standard Progressive Matrices in 316 MZ and 550 same-sex DZ twins with a mean age of 10 years in Sudan. Heritability was estimated at 0.172 and shared environmental influences at 0.596.