Individual Cross-sectional Data Research Articles

Health of singleton neonates in Switzerland through time and crises: a cross-sectional study at the population level, 2007-2022

BackgroundBeing exposed to crises during pregnancy can affect maternal health through stress exposure, which can in return impact neonatal health. We investigated temporal trends in neonatal outcomes in Switzerland between 2007 and 2022 and their variations depending on exposure to the economic crisis of 2008, the flu pandemic of 2009, heatwaves (2015 and 2018) and the COVID-19 pandemic.MethodsUsing individual cross-sectional data encompassing all births occurring in Switzerland at the monthly level (2007-2022), we analysed changes in birth weight and in the rates of preterm birth (PTB) and stillbirth through time with generalized additive models. We assessed whether the intensity or length of crisis exposure was associated with variations in these outcomes. Furthermore, we explored effects of exposure depending on trimesters of pregnancy.ResultsOver 1.2 million singleton births were included in our analyses. While birth weight and the rate of stillbirth have remained stable since 2007, the rate of PTB has declined by one percentage point. Exposure to the crises led to different results, but effect sizes were overall small. Exposure to COVID-19, irrespective of the pregnancy trimester, was associated with a higher birth weight (+12 grams [95% confidence interval (CI) 5.5 to 17.9 grams]). Being exposed to COVID-19 during the last trimester was associated with an increased risk of stillbirth (odds ratio 1.24 [95%CI 1.02 to 1.50]). Exposure to the 2008 economic crisis during pregnancy was not associated with any changes in neonatal health outcomes, while heatwave effect was difficult to interpret.ConclusionOverall, maternal and neonatal health demonstrated resilience to the economic crisis and to the COVID-19 pandemic in a high-income country like Switzerland. However, the effect of exposure to the COVID-19 pandemic is dual, and the negative impact of maternal infection on pregnancy is well-documented. Stress exposure and economic constraint may also have had adverse effects among the most vulnerable subgroups of Switzerland. To investigate better the impact of heatwave exposure on neonatal health, weekly or daily-level data is needed, instead of monthly-level data.

The influence of depressive symptoms and school-going status on risky behaviors: a pooled analysis among adolescents in six sub-Saharan African countries.

Evidence from sub-Saharan Africa (SSA) regarding risky behaviors among adolescents remains scarce, despite the large population (approximately 249 million out of 1.2 billion globally in 2019) of adolescents in the region. We aimed to examine the potential influence of depressive symptoms and school-going status on risky behaviors among adolescents in six SSA countries. We used individual cross-sectional data from adolescents aged 10-19 based in eight communities across six SSA countries, participating in the ARISE Network Adolescent Health Study (N = 7,661). Outcomes of interest were cigarette or tobacco use, alcohol use, other substance use, getting into a physical fight, no condom use during last sexual intercourse, and suicidal behavior. We examined the proportion of adolescents reporting these behaviors, and examined potential effects of depressive symptoms [tertiles of 6-item Kutcher Adolescent Depression Scale (KADS-6) score] and school-going status on these behaviors using mixed-effects Poisson regression models. We also assessed effect modification of associations by sex, age, and school-going status. The proportion of adolescents reporting risky behaviors was varied, from 2.2% for suicidal behaviors to 26.2% for getting into a physical fight. Being in the higher tertiles of KADS-6 score was associated with increased risk of almost all risky behaviors [adjusted risk ratio (RR) for highest KADS-6 tertile for alcohol use: 1.70, 95% confidence interval (95% CI): 1.48-1.95, p < 0.001; for physical fight: 1.52, 95% CI: 1.36-1.70, p < 0.001; for suicidal behavior: 7.07, 95% CI: 2.69-18.57, p < 0.001]. Being in school was associated with reduced risk of substance use (RR for alcohol use: 0.73, 95% CI: 0.53-1.00, p = 0.047), and not using a condom (RR: 0.81, 95% CI: 0.66-0.99, p = 0.040). There was evidence of modification of the effect of school-going status on risky behaviors by age and sex. Our findings reinforce the need for a greater focus on risky behaviors among adolescents in SSA. Addressing depressive symptoms among adolescents, facilitating school attendance and using schools as platforms to improve health may help reduce risky behaviors in this population. Further research is also required to better assess the potential bidirectionality of associations.

Socio-Economic Factors Influencing Consumers Online Purchase Behavior of Food Products in Bangalore City

Background: Online purchase has a very important role to play in creating consistent demand for farmers’ products and linking them directly to final consumers. Preferences of consumers are the most important driver of online purchases that prosper the linkage between farmers and the final consumers and these preferences are vastly influenced by consumers’ socio-economic characteristics. The current study was conducted to analyse the influence of socio-economic factors on the online purchase of food products in Bangalore city. Methods: Individual cross-sectional data were collected using a pre-tested questionnaire from 105 consumers of randomly selected areas of Bangalore city namely, Sahakarnagar, Judicial Layout, Yelahanka, Canara bank layout, Mahadevapura, Sanjaynagar and Jayanagar. Binary logistic regression was applied as the research method to examine the influence of socio-economic characteristics like gender, age, occupation, education, number of family members with income and income (as predictor variables) towards the online purchase of food products (as dependent variable). Result: Results indicated that age (negatively), number of family members earning income and monthly income (positively) significantly influenced the online purchase of food products. Other variables like education, gender (in favour of men) and occupation also influenced (positively) the outcome variable but, statistically were not significant.

Trade liberalization and wage inequality: Evidence from Chile

This study analyzes the impacts of further tariff reductions resulting from the proliferation of regional trade agreements on wage inequality between skilled and unskilled workers in Chile in the 2000s. I match panel data on industry-level effective tariff rates and other industry variables calculated from plant-level microdata to pooled individual cross-section data from national household surveys at the industry level. Based on this unique data set, I estimate the impacts of effective tariffs on workers’ wages directly in one stage. I find that a reduction in effective tariffs on final goods leads to an increase in industry wage and skill premiums. Moreover, the impact on the industry skill premiums is larger for skilled workers employed in large-sized firms. Therefore, the findings indicate that increased import competition due to reductions in output tariffs leads to skill upgrading within industries, thereby increasing demand for skilled workers. The results are robust to the possible endogeneity of effective tariffs and the inclusion of industry-level productivity.

A detailed decomposition analysis of the public-private sector wage gap in South Africa

ABSTRACTThe present study examines the public-private sector wage gap in South Africa using individual cross-sectional data for 2000–14. Results from unconditional quantile regressions and generalised Oaxaca–Blinder type decompositions show that the wage gap is an inverted-U shape across the wage distribution. The ‘composition effect’ is more important than the ‘price effect’ at the bottom of the distribution while the opposite applies at the top. Key factors underpinning the ‘composition effect’ are unionisation, industry of employment and education, while those associated with the ‘price effect’ are education, race and occupation.

Determinants of Black Women's Labour Force Participation in Post-Apartheid South Africa

This paper investigates the changes that occurred in black South African women's labour force participation (LFP) over the 1995–2004 post-Apartheid period. Using regression analysis of individual cross-section data for 1995, 1999 and 2004, we show that throughout this period higher education and urban residence were associated with higher LFP, whereas the reverse was the case for ‘non-labour income’, marriage and fertility. We also find that the increase in black women's LFP between 1995 and 2004 could be attributable mainly to increases in the returns rather than to changes in their labour market characteristics.

Joint Modeling of HCV and HIV Co-Infection among Injecting Drug Users in Italy and Spain Using Individual Cross-Sectional Data

The aim of the analysis presented in this paper is to study co-infection with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) in injecting drug users (IDUs) using a joint modeling approach that makes use of multivariate statistical methods for current status data. Using marginal models, we estimate association measures between HCV and HIV infections at individual level, i.e., odds ratios and correlation coefficients, and we regress them against some risk factors, e.g., the length of the injecting career, the age at first injection, the ever sharing of syringes, and the frequency of current injecting. In addition, we fit random-effects models that take into account the individual heterogeneity in the acquisition of the infections. For our analysis, we use cross-sectional data from two independent serological surveys, one carried out in Italy (IT) in 2005 on 856 subjects, and the other in three Spanish (ES) cities, between 2001 and 2003, on 589 subjects. We found that the infections are positively associated within individuals, e.g., ORIT=2.56 with 95% confidence interval (CI) (1.43, 6.68) and ORES= 2.42, with 95% CI (1.41, 4.30). We found that the odds ratio and the correlation between HCV and HIV infections increase positively with the length of the injecting career. Moreover, they are found to be significantly positive in case IDUs have never shared syringes or report low injecting frequencies. The variance of the individual random effects is positive, e.g., σb2=0.34 (0.14, 0.62), indicating that there is significant individual heterogeneity in the acquisition of the infections. Our results show that a significant association between HCV and HIV infections within IDUs is related to significant individual heterogeneity in the acquisition of the infections. Indeed, the association between these infections in IDUs who report ever sharing syringes is not significant, which can be explained by a higher homogeneity in their behaviors and, therefore, in their acquisition of the infections.

New results on the neutron-induced fission cross-section of 231Pa for incident neutron energies En = 0.8–3.5 MeV

New results on the neutron-induced fission cross-section of 231Pa in the incident neutron energy range between E n = 0.8 and 3.5 MeV are presented. The individual cross-section data are obtained within an uncertainty of less than 5% and meets the accuracy required by the IAEA in the summary report of the consultants’ meeting on “Assessment of Nuclear Data Needs for Thorium and other Advanced Cycles” from 1999. With the new data the hitherto existing large spread between evaluated data files may be removed.

Two-Stage Budgeting and Exact Aggregation

This paper presents an econometric model of demand for energy based on two-stage budgeting. The model provides own-price and cross-price elasticities of demand for energy and nonenergy commodities for the United States. These elasticities are estimated separately for households classified by family size, age of head, region, race, and urban versus rural residence. Price elasticities are presented conditional on total energy expenditure and total expenditure on all commodities. The model combines individual cross-section data with aggregate time series data and is based on exact aggregation over individual demand functions.

Aggregate Consumer Behavior and Household Equivalence Scales

This article presents estimates of household equivalence scales, broken down by demographic characteristics, of U.S. households. Separate estimates are given by family size, age of head, region, race, and urban versus rural residence. Commodity-specific scales are presented for five separate commodity groups—energy, food, consumer goods, capital services, and other services. The estimates are obtained from an econometric model of aggregate consumer behavior. The parameters of this model are estimated by combining aggregate time series and individual cross-section data.

Trends in female labor force participation in Sweden.

The labor force participation of Swedish married women increased form 49.1% to 83.5% in the past 2 decades. Results from cross section analyses carried out on micro data from 3 standard of living investigations, done in 1968, 1974, and 1981, are used to predict changes over time. Women's real wages have increased over time more than men's real wages; in combination with estimated positve own wages elasticities, this change is the most important determinant of the increase in female labor supply. The labor force participation of married women ages 20-59 has increased from 49.1% in 1963 to 83.5% in 1982; the increase is especially large for women with children under 7. Over the decades 1920-1965, when real wages of woman increased more than real incomes of men, the labor force participation rates of married women increased even faster. From 1963-1981 a dramatic narrowing of the male-female wage gap occurred; most of the decrease is a result of factors other than the human capital variables accumulated at school and on the job. The effect of centralized collective bargaining and a strong union policy to increase low wages may be important explanatory factors. Generous parental leaves and subsidized day care may have an increasing effect on fertility; but instead, fertility has decreased, perhaps less than it might have done in the absence of such policies. By using individual cross section data from the 3 standard of living investigations, estimates of participation are performed. The own wage effects of the participation equation are positive and significant but decreasing over time. Important institutional changes between the sample periods are the extended parental leaves and the increased supply of government subsidized day care.

The Use of Cross-Section Data to Characterize Macro Functions

Abstract This article investigates the use of individual cross-section data to describe macro functions. Necessary and sufficient conditions (denoted by AS) are found for ordinary least squares (OLS) slope coefficients from a cross section to consistently estimate the first derivatives of the macro function. AS embodies both sets of aggregation assumptions known; linear aggregation and sufficient statistics, and thus represents generalized aggregation conditions. A methodology is given for estimating second-order derivatives of the macro function from cross-section data for distributions of the exponential family, which extends to higher-order derivatives. Finally, a general test of linear aggregation schemes is presented.