279 research outputs found
Tax burden and incidence in the history of taxation by state governments
The objective of this paper is to view the twentieth century changes in the structure of state taxation in a historical perspective to understand the tax burden acceptable at the state level and the incidence of that tax incidence from proportional to progressive taxes and vice versa. The tax burden and incidence in four different states from four different regions of the country, California, Indiana, Kentucky, and New York, will then be compared for the decade of the 1970\u27s to determine if a pattern of change in the tax burden and tax incidence existed at the time of the revolts
Non-response bias in estimates of HIV prevalence due to the mobility of absentees in national population-based surveys: a study of nine national surveys
OBJECTIVES: To measure the bias in national estimates of HIV prevalence in population-based surveys caused by mobility and refusal to test. METHODS: Data from nine demographic and health surveys and AIDS indicator surveys were used. Non-responders were divided into three groups: (i) "refusals" who were interviewed but not tested; (ii) "refusals" who were present in the household but not interviewed or tested; and (iii) "absentees" who were absent from the household. Correction for HIV status was made for the non-responders using multiple imputation methods with logistic regression models based on a common set of household-level and individual-level sociodemographic and behavioural factors for those tested and stratified by mobility status. RESULTS: The non-response groups were corrected to have higher risks of HIV than those who participated in the HIV tests, although these were only detected to be statistically significant in some of the countries. In Lesotho, the corrected prevalence for the absent household members was significantly higher than for those who were present in the household. However, the adjusted prevalences differed by less than a percentage point from the prevalences observed among those who were tested, so the overall effects of non-response on national estimates of HIV prevalence are minimal. CONCLUSIONS: The results indicate that the mobility of absentees does not substantially bias estimates of HIV prevalence from population-based surveys. None the less, if levels of non-response are high or if non-responders differ greatly from those who participate in HIV testing with respect to HIV status, non-response could still bias national estimates of HIV prevalence
Influence of timing of sexual debut and first marriage on sexual behaviour in later life: findings from four survey rounds in the Kisesa cohort in northern Tanzania
OBJECTIVES: To evaluate quality of sexual debut and first marriage data, measure trends and study the association of risky sexual behaviour in youth with adult risk behaviour. METHODS: Reports on age at first sex (AFS) and age at first marriage (AFM) from the Kisesa cohort study, 1994-2004, were evaluated for consistency and used to describe trends in median age-at-event and time spent single but sexually active in different birth cohorts. The association of these variables with marital stability and numbers of partners at later ages was explored using statistical regression techniques. RESULTS: AFS and AFM were inconsistently reported by 32% and 33% of respondents, respectively, but there was no general tendency to report lower or higher ages at a later report date. In 10-year birth cohorts born between 1950-9 and 1980-9, male median AFS declined from 18.1 to 17.0 years and female median AFM rose from 16.2 to 16.6 years. Young people of both sexes currently spend longer sexually active but unmarried than previously. Early marriage is statistically associated with remarriage and polygamy; longer time between sexual debut and marriage is associated with higher numbers of partners at later stages of life. CONCLUSION: Inconsistent reporting of age-at-event introduces noise but does not bias estimates of population level indicators. Lengthening time spent single and sexually active suggests that men and women entering first marriage will have been exposed to increased numbers of non-marital partners. Successful youth interventions may also influence adult behaviour
Embracing different approaches to estimating HIV incidence, prevalence and mortality
Background: Joint United Nations Programme on HIV/AIDS (UNAIDS) and Murray et al. have both produced sets of estimates for worldwide HIV incidence, prevalence and mortality. Understanding differences in these estimates can strengthen the interpretation of each
Trends in sexual activity and demand for and use of modern contraceptive methods in 74 countries. A retrospective analysis of nationally representative surveys
Background A quarter of a century ago, two global events—the International Conference on Population and Development
in Cairo, and the Fourth World Conference on Women in Beijing—placed gender equality and reproductive health and
rights at the centre of the development agenda. Progress towards these goals has been slower than hoped. We used
survey data and national-level indicators of social determinants from 74 countries to examine change in satisfaction of
contraceptive need from a contextual perspective.
Methods We searched for individual-level data from repeated nationally representative surveys that included information
on sexual and reproductive health, and created a single dataset by harmonising data from each survey to a standard data
specification. We described the relative timings of sexual initiation, first union (cohabitation or marriage), and first birth
and used logistic regression to show the change in prevalence of sexual activity, demand for contraception, and modern
contraceptive use. We used linear regression to examine country-level associations between the gender development
index and the expected length of time in education for women and the three outcomes: sexual activity, demand for
contraception, and modern contraceptive use. We used principal component analysis to describe countries using a
combination of social-structural and behavioural indicators and assessed how well the components explained countrylevel variation in the proportion of women using contraception with fractional logistic regression.
Findings In 34 of the 74 countries examined, proportions of all women who were sexually active, not wanting to conceive,
and not using a modern contraceptive method decreased over time. Proportions of women who had been sexually active
in the past year changed over time in 43 countries, with increases in 30 countries; demand for contraception increased in
42 countries, and use of a modern method of contraception increased in 37 countries. Increases over time in met need
for contraception were correlated with increases in gender equality and with women’s time in education. Regression
analysis on the principal components showed that country-level variation in met contraceptive need was largely explained
by a single component that combined behavioural and social-contextual variables.
Interpretation Progress towards satisfying demand for contraception should take account of the changing context in
which it is practised. To remove the remaining barriers, policy responses—and therefore research priorities—could
require a stronger focus on social-structural determinants and broader aspects of sexual health.
Funding UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research
Training in Human Reproduction
Use of microsatellite-based paternity assignment to establish where Corn Crake <i>Crex crex</i> chicks are at risk from mechanized mowing
We used microsatellite DNA to assign probable parentage of young Corn Crakes to adult males and females and used these assignments to estimate the distribution of distances between broods of chicks and juveniles and the night-time singing place of the father at the time of initiation of the clutch. Estimated distances for broods of young chicks were in accord with those estimated previously by radiotracking, but distances were greater for older unfledged independent chicks not studied previously. Our results indicate that modifications of the timing and method of mowing to reduce losses of nests and chicks should be implemented inside an area within about 500Â m of the singing places of male Corn Crakes, rather than the 250Â m previously considered to be safe
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Local and long-distance migration among young people in rural Malawi: importance of age, sex and family
Data availability statement:
Underlying data:
Due to the nature of the dataset (containing exact GPS coordinates of individuals households and potentially unique patterns of local relatives), it would not be possible to anonymise it in such a way that would sufficiently protect the participants’ privacy and allow for useful analyses. MEIRU are, however, keen to share data and collaborate with bona fide researchers and students at universities and research institutes. Interested parties should contact the first author [EM] through [email protected] in the first instance, quoting the paper title. After a discussion of data needed, a signed data transfer agreement would be required. Metadata on the MEIRU dataset which formed the basis of these analyses can be found, along with information on other studies, on MEIRU’s data catalogue (https://kpsmw.lshtm.ac.uk/nada/index.php/catalog/13),Analysis code:
Zenodo: Local and long-distance migration among young people in rural Malawi: importance of age, sex and family (author-written code & extended data table). Author-written code in Stata, R and MLwiN, and extended data table for article published on Wellcome Open Research. https://doi.org/10.5281/zenodo.10812334
This project contains the following files:
ExtData_full_regression_models.xlsx An excel file with results from full regression models
Prog1_create_migration_datasets.do A Stata do-file containing code to manipulate the main dataset into the analytical dataset
Prog2_explo_desc_analysis.do A Stata do-file containing code for the exploratory and descriptive analyses reported in this paper
Prog3_prepare_forR_Sankey.do A Stata do-file containing code to manipulate the analytical dataset into the format required to generate the Sankey diagrams in R
Prog4_prepare_forMLwinN_Modelv2.do A Stata do-file containing code to manipulate the analytical dataset into the format required to run the multi-level modelling using MLwiN
Prog5_sankey_plots.R An R script containing code to generate the Sankey diagrams reported in this paper
Prog6_MLwiN_modelsv2.txt An MLwiN macro containing code to run the multi-level models reported in this paper
Data are available under the terms of the Creative Commons Attribution 4.0 InternationalBackground:
In sub-Saharan Africa, migration of young people is common and occurs for a variety of reasons. Research focus is often on international or long-distance internal migration; however, shorter moves also affect people’s lives and can reveal important information about cultures and societies. In rural sub-Saharan Africa, migration may be influenced by cultural norms and family considerations: these may be changing due to demographic shifts, urbanisation, and increased media access.
Methods:
We used longitudinal data from a Health and Demographic Surveillance Site in rural northern Malawi to present a detailed investigation of migration in young people between 2004–2017. Our focus is on the cultural effects of gender and family, and separate migrations into short and long distance, and independent and accompanied, as these different move types are likely to represent very different events in a young person’s life. We use descriptive analyses multi-level multinomial logistic regression modelling.
Results & conclusions:
We found two key periods of mobility 1) in very young childhood and 2) in adolescence/young adulthood. In this traditionally patrilocal area, we found that young women move longer distances to live with their spouse, and also were more likely to return home after a marriage ends, rather than remain living independently. Young people living close to relatives tend to have lower chances of moving, and despite the local patrilineal customs, we found evidence of the importance of the maternal family. Female and male children may be treated differently from as young as age 4, with girls more likely to migrate long distances independently, and more likely to accompany their mothers in other moves.This work is supported by The Wellcome Trust (098610; 217073; through funds awarded to Amelia Crampin and The Karonga HDSS)
Trends in the burden of HIV mortality after roll-out of antiretroviral therapy in KwaZulu-Natal, South Africa: an observational community cohort study.
Antiretroviral therapy (ART) substantially decreases morbidity and mortality in people living with HIV. In this study, we describe population-level trends in the adult life expectancy and trends in the residual burden of HIV mortality after the roll-out of a public sector ART programme in KwaZulu-Natal, South Africa, one of the populations with the most severe HIV epidemics in the world.
Data come from the Africa Centre Demographic Information System (ACDIS), an observational community cohort study in the uMkhanyakude district in northern KwaZulu-Natal, South Africa. We used non-parametric survival analysis methods to estimate gains in the population-wide life expectancy at age 15 years since the introduction of ART, and the shortfall of the population-wide adult life expectancy compared with that of the HIV-negative population (ie, the life expectancy deficit). Life expectancy gains and deficits were further disaggregated by age and cause of death with demographic decomposition methods.
Covering the calendar years 2001 through to 2014, we obtained information on 93 903 adults who jointly contribute 535 42 8 person-years of observation to the analyses and 9992 deaths. Since the roll-out of ART in 2004, adult life expectancy increased by 15·2 years for men (95% CI 12·4-17·8) and 17·2 years for women (14·5-20·2). Reductions in pulmonary tuberculosis and HIV-related mortality account for 79·7% of the total life expectancy gains in men (8·4 adult life-years), and 90·7% in women (12·8 adult life-years). For men, 9·5% is the result of a decline in external injuries. By 2014, the life expectancy deficit had decreased to 1·2 years for men (-2·9 to 5·8) and to 5·3 years for women (2·6-7·8). In 2011-14, pulmonary tuberculosis and HIV were responsible for 84·9% of the life expectancy deficit in men and 80·8% in women.
The burden of HIV on adult mortality in this population is rapidly shrinking, but remains large for women, despite their better engagement with HIV-care services. Gains in adult life-years lived as well as the present life expectancy deficit are almost exclusively due to differences in mortality attributed to HIV and pulmonary tuberculosis.
Wellcome Trust, the Bill & Melinda Gates Foundation, and the National Institutes of Health
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