An accurate test for homogeneity of odds ratios based on Cochran's Q-statistic

Background: A frequently used statistic for testing homogeneity in a meta-analysis of K independent studies is Cochran's Q. For a standard test of homogeneity the Q statistic is referred to a chi-square distribution with K - 1 degrees of freedom. For the situation in which the effects of the studies are logarithms of odds ratios, the chi-square distribution is much too conservative for moderate size studies, although it may be asymptotically correct as the individual studies become large. Methods: Using a mixture of theoretical results and simulations, we provide formulas to estimate the shape and scale parameters of a gamma distribution to t the distribution of Q. Results: Simulation studies show that the gamma distribution is a good approximation to the distribution for Q. Conclusions: : Use of the gamma distribution instead of the chi-square distribution for Q should eliminate inaccurate inferences in assessing homogeneity in a meta-analysis. (A computer program for implementing this test is provided.) This hypothesis test is competitive with the Breslow-Day test both in accuracy of level and in power

How Does Inequality of Opportunities Affect the Distribution of Economic Wellbeing in Cameroon

The objective of this study is to measure the empirical effects of inequality of opportunities (IOP) on the distribution of economic wellbeing, which is captured by consumption per adult equivalent of households in Cameroon. To this effect, we apply both the parametric and non-parametric approaches to measure the magnitude of IOP, and Shapley’s method for its decomposition. The results show that IOP has an estimated effect of 25% in 2001 and 35% in 2007. Its main sources are the agro-ecological zone with a contribution of 45.59% in 2001 and 44% in 2007, the place of residence with a contribution of 31.22% in 2001 and 29.49% in 2007, and the distance relative to a good road with a contribution of 12.57% and 13.83%, respectively. We recommend that the government should reinforce national integration policies for local agricultural product markets. She should also extend in rural areas, vocational training that characterizes human capital in urban areas; and she should expand and improve road infrastructure, especially in rural areas

Economic Growth and Poverty in Cameroon: the role of Employment

This study investigates empirically the effect of employment in the transmission of economic growth to poverty change in Cameroon. Using data covering the period 1991 to 2017. We estimate two models: the employment intensity of growth model of Kapsos; and the Loayza and Raddatz model, which assesses the impact of sectoral employment intensity of economic growth to the change in poverty. Analyses highlight two main results. First, economic growth positively affects employment and negatively affects poverty rates. Second, the transmission of economic growth through employment is not effective in reducing poverty in Cameroon. These results show that in recent decades, economic growth has propelled the creation of employment in Cameroon. However, these employments, which are mostly precarious, generated by the informal sector, have not significantly reduced poverty

Economic Growth and Poverty in Cameroon: the role of Employment

This study investigates empirically the effect of employment in the transmission of economic growth to poverty change in Cameroon. Using data covering the period 1991 to 2017. We estimate two models: the employment intensity of growth model of Kapsos; and the Loayza and Raddatz model, which assesses the impact of sectoral employment intensity of economic growth to the change in poverty. Analyses highlight two main results. First, economic growth positively affects employment and negatively affects poverty rates. Second, the transmission of economic growth through employment is not effective in reducing poverty in Cameroon. These results show that in recent decades, economic growth has propelled the creation of employment in Cameroon. However, these employments, which are mostly precarious, generated by the informal sector, have not significantly reduced poverty

Calcitization of aragonitic bryozoans in Cenozoic tropical carbonates from East Kalimantan, Indonesia

© The Author(s) 2016. Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The file attached is the published version of the article

Persistence of the immune response induced by BCG vaccination.

BACKGROUND: Although BCG vaccination is recommended in most countries of the world, little is known of the persistence of BCG-induced immune responses. As novel TB vaccines may be given to boost the immunity induced by neonatal BCG vaccination, evidence concerning the persistence of the BCG vaccine-induced response would help inform decisions about when such boosting would be most effective. METHODS: A randomised control study of UK adolescents was carried out to investigate persistence of BCG immune responses. Adolescents were tested for interferon-gamma (IFN-gamma) response to Mycobacterium tuberculosis purified protein derivative (M.tb PPD) in a whole blood assay before, 3 months, 12 months (n = 148) and 3 years (n = 19) after receiving teenage BCG vaccination or 14 years after receiving infant BCG vaccination (n = 16). RESULTS: A gradual reduction in magnitude of response was evident from 3 months to 1 year and from 1 year to 3 years following teenage vaccination, but responses 3 years after vaccination were still on average 6 times higher than before vaccination among vaccinees. Some individuals (11/86; 13%) failed to make a detectable antigen-specific response three months after vaccination, or lost the response after 1 (11/86; 13%) or 3 (3/19; 16%) years. IFN-gamma response to Ag85 was measured in a subgroup of adolescents and appeared to be better maintained with no decline from 3 to 12 months. A smaller group of adolescents were tested 14 years after receiving infant BCG vaccination and 13/16 (81%) made a detectable IFN-gamma response to M.tb PPD 14 years after infant vaccination as compared to 6/16 (38%) matched unvaccinated controls (p = 0.012); teenagers vaccinated in infancy were 19 times more likely to make an IFN-gamma response of > 500 pg/ml than unvaccinated teenagers. CONCLUSION: BCG vaccination in infancy and adolescence induces immunological memory to mycobacterial antigens that is still present and measurable for at least 14 years in the majority of vaccinees, although the magnitude of the peripheral blood response wanes from 3 months to 12 months and from 12 months to 3 years post vaccination. The data presented here suggest that because of such waning in the response there may be scope for boosting anti-tuberculous immunity in BCG vaccinated children anytime from 3 months post-vaccination. This supports the prime boost strategies being employed for some new TB vaccines currently under development

Safety, potential efficacy, and pharmacokinetics of specific polyclonal immunoglobulin F(ab')<inf>2</inf> fragments against avian influenza A (H5N1) in healthy volunteers: A single-centre, randomised, double-blind, placebo-controlled, phase 1 study

The Lancet Infectious Diseases153285-29

Needs assessment to strengthen capacity in water and sanitation research in Africa:experiences of the African SNOWS consortium

Despite its contribution to global disease burden, diarrhoeal disease is still a relatively neglected area for research funding, especially in low-income country settings. The SNOWS consortium (Scientists Networked for Outcomes from Water and Sanitation) is funded by the Wellcome Trust under an initiative to build the necessary research skills in Africa. This paper focuses on the research training needs of the consortium as identified during the first three years of the project

Is telomere length socially patterned? Evidence from the West of Scotland Twenty-07 study

Lower socioeconomic status (SES) is strongly associated with an increased risk of morbidity and premature mortality, but it is not known if the same is true for telomere length, a marker often used to assess biological ageing. The West of Scotland Twenty-07 Study was used to investigate this and consists of three cohorts aged approximately 35 (N = 775), 55 (N = 866) and 75 years (N = 544) at the time of telomere length measurement. Four sets of measurements of SES were investigated: those collected contemporaneously with telomere length assessment, educational markers, SES in childhood and SES over the preceding twenty years. We found mixed evidence for an association between SES and telomere length. In 35-year-olds, many of the education and childhood SES measures were associated with telomere length, i.e. those in poorer circumstances had shorter telomeres, as was intergenerational social mobility, but not accumulated disadvantage. A crude estimate showed that, at the same chronological age, social renters, for example, were nine years (biologically) older than home owners. No consistent associations were apparent in those aged 55 or 75. There is evidence of an association between SES and telomere length, but only in younger adults and most strongly using education and childhood SES measures. These results may reflect that childhood is a sensitive period for telomere attrition. The cohort differences are possibly the result of survival bias suppressing the SES-telomere association; cohort effects with regard different experiences of SES; or telomere possibly being a less effective marker of biological ageing at older ages

Combinatorial CRISPR-Cas9 screens for de novo mapping of genetic interactions.

We developed a systematic approach to map human genetic networks by combinatorial CRISPR-Cas9 perturbations coupled to robust analysis of growth kinetics. We targeted all pairs of 73 cancer genes with dual guide RNAs in three cell lines, comprising 141,912 tests of interaction. Numerous therapeutically relevant interactions were identified, and these patterns replicated with combinatorial drugs at 75% precision. From these results, we anticipate that cellular context will be critical to synthetic-lethal therapies