Dichotomisation using a distributional approach when the outcome is skewed

Sauzet O, Ofuya M, Peacock JL. Dichotomisation using a distributional approach when the outcome is skewed. BMC Medical Research Methodology. 2015;15(1): 40.Background Dichotomisation of continuous outcomes has been rightly criticised by statisticians because of the loss of information incurred. However to communicate a comparison of risks, dichotomised outcomes may be necessary. Peacock et al. developed a distributional approach to the dichotomisation of normally distributed outcomes allowing the presentation of a comparison of proportions with a measure of precision which reflects the comparison of means. Many common health outcomes are skewed so that the distributional method for the dichotomisation of continuous outcomes may not apply. Methods We present a methodology to obtain dichotomised outcomes for skewed variables illustrated with data from several observational studies. We also report the results of a simulation study which tests the robustness of the method to deviation from normality and assess the validity of the newly developed method. Results The review showed that the pattern of dichotomisation was varying between outcomes. Birthweight, Blood pressure and BMI can either be transformed to normal so that normal distributional estimates for a comparison of proportions can be obtained or better, the skew-normal method can be used. For gestational age, no satisfactory transformation is available and only the skew-normal method is reliable. The normal distributional method is reliable also when there are small deviations from normality. Conclusions The distributional method with its applicability for common skewed data allows researchers to provide both continuous and dichotomised estimates without losing information or precision. This will have the effect of providing a practical understanding of the difference in means in terms of proportions

World report on violence and health

This report examines the types of violence that are present worldwide, in the everyday lives of people, and that constitute the bulk of the health burden imposed by violence. Accordingly, the information has been arranged in nine chapters, covering the following topics: 1. Violence – a global public health problem 2. Youth violence 3. Child abuse and neglect by parents and other caregivers 4. Violence by intimate partners 5. Abuse of the elderly 6. Sexual violence 7. Self-directed violence 8. Collective violence 9. The way forward: recommendations for action; Because it is impossible to cover all types of violence fully and adequately in a single document, each chapter has a specific focus. For example, the chapter on youth violence examines interpersonal violence among adolescents and young adults in the community. The chapter on child abuse discusses physical, sexual and psychological abuse, as well as neglect by parents and other caregivers; other forms of maltreatment of children, such as child prostitution and the use of children as soldiers, are covered in other parts of the report. The chapter on abuse of the elderly focuses on abuse by caregivers in domestic and institutional settings, while that on collective violence discusses violent conflict. The chapters on intimate partner violence and sexual violence focus primarily on violence against women, though some discussion of violence directed at men and boys is included in the chapter on sexual violence. The chapter on self-directed violence focuses primarily on suicidal behaviour. The chapter is included in the report because suicidal behaviour is one of the external causes of injury and is often the product of many of the same underlying social, psychological and environmental factors as other types of violence. The chapters follow a similar structure. Each begins with a brief discussion of definitions for the specific type of violence covered in the chapter, followed by a summary of current knowledge about the extent of the problem in different regions of the world. Where possible, country-level data are presented, as well as findings from a range of research studies. The chapters then describe the causes and consequences of violence, provide summaries of the interventions and policy responses that have been tried, and make recommendations for future research and action. Tables, figures and boxes are included to highlight specific epidemiological patterns and findings, illustrate examples of prevention activities, and draw attention to specific issues. The report concludes with two additional sections: a statistical annex and a list of Internet resources. The statistical annex contains global, regional and country data derived from the WHO mortality and morbidity database and from Version 1 of the WHO Global Burden of Disease project for 2000. A description of data sources and methods is provided in the annex to explain how these data were collected and analysed. The list of Internet resources includes web site addresses for organizations involved in violence research, prevention and advocacy. The list includes metasites (each site offers access to hundreds of organizations involved in violence research, prevention and advocacy), web sites that focus on specific types of violence, web sites that address broader contextual issues related to violence, and web sites that offer surveillance tools for improving the understanding of violence

Potensi Senyawa Polifenol Antioksidan Dari Pisang Goroho (Musa Sapien SP.)

Goroho banana is food material that has positive content effect on human body. The aims of this research were toanalyze polyphenolic content and to examine antioxidant activity of goroho. Polyphenolic antioxidant of goroho was extracted using methanol, ethanol and acetone for 2 hours at room temperature. Furthermore. extract was analyzed polyphenol content, such as total phenolic, total flavonoidand condensed tannin content. To examine antioxidant activity, free radical DPPH scavenging and total antioxidant (FRAP) were used by spectrophotometer analysis. Beside that, the best extract was evaluated its heat stability at 1000C for 15, 30, 45, 60 and 120 minutes.The highest total phenolic content was in acetone extract 181.87 mg/kg sample, total flavonoid content 4.75 mg/ kg sample in ethanol extract and condensed tannin 54.63 mg/kg sample in aceton extract. Acetone extract of goroho show the highest free radical scavenging activity (94.32%) compare to ethanol extract (85.39 %) and methanol extract (76.38 %). Although examination of total antioxidant (FRAP) on aceton extract of goroho showed the highest content than methanol and ethanol extract. Total antioxidant from acetone, methanol and ethanol extract were 1.83; 1.74; and1.74 μmol/L. This examination resulted that at 1000C there are alterations in phenolic content, free radical scavenging activity and total antioxidant after heating 120 minutes, although this three parameters alteration did not show extremedecreasing after 60 minute heating, because it still possess high activity, more than 80%. This result indicate goroho extract stability on heating depend on heating time. This results concluded that goroho possess to phenolic, flavonoid and tannin, also antioxidant activity

Community perceptions and practices of treatment seeking for childhood pneumonia: a mixed methods study in a rural district, Ghana

Abstract Background The World Health Organization recommends community case management of malaria and pneumonia for reduction of under-five mortality in developing countries. Caregivers’ perception and understanding of the illness influences the care a sick child receives. Studies in Ghana and elsewhere have routinely shown adequate recognition of malaria by caregivers. Similarly, evidence from Asia and some African countries have shown adequate knowledge on pneumonia. However, in Ghana, little has been documented about community awareness, knowledge, perceptions and management of childhood pneumonia particularly in the Dangme West district. Therefore this formative study was conducted to determine community perceptions of pneumonia for the purpose of informing the design and implementation of context specific health communication strategies to promote early and appropriate care seeking behaviour for childhood pneumonia. Methods A mixed method approach was adopted. Data were obtained from structured interviews (N = 501) and eight focus group discussions made up of 56 caregivers of under-fives and eight community Key Informants. Descriptive and inference statistics were used for the quantitative data and grounded theory to guide the analysis of the qualitative data. Results Two-thirds of the respondents had never heard the name pneumonia. Most respondents did not know about the signs and symptoms of pneumonia. For the few who have heard about pneumonia, causes were largely attributed to coming into contact with cold temperature in various forms. Management practices mostly were self-treatment with home remedies and allopathic care. Conclusion The low awareness and inadequate recognition of pneumonia implies that affected children may not receive prompt and appropriate treatment as their caregivers may misdiagnose the illness. Adequate measures need to be taken to create the needed awareness to improve care seeking behaviour

A Study of the Corrosion Inhibition of Mild Steel in 0.5M Tetraoxosulphate (VI) acid by Alstonia boonei Leaves Extract as an Inhibitor at Different Temperatures

A comparative study of the corrosion inhibition performance of Alstonia boonei leaves extract in 0.5M tetraoxosulphate (VI) acid at different temperatures (30ᵒC, 50ᵒC and 70ᵒC) was undertaken. The results showed that Alstonia boonei leaves extract was more efficient as a corrosion inhibitor at 30ᵒC compared to temperatures of 50ᵒC and 70ᵒC.The adsorption of Alstonia boonei leaves extract was found to obey Langmuir adsorption isotherm at all temperatures (30ᵒC, 50ᵒC and 70ᵒC), but did not obey Freundlich adsorption isotherm at all temperatures. A study of the effect of temperature on corrosion rate and inhibition efficiency showed that corrosion rate increased with increase in temperature, while the inhibition efficiency decreased with increase in temperature

Secondary bacterial infections of buruli ulcer lesions before and after chemotherapy with streptomycin and rifampicin

Buruli ulcer (BU), caused by Mycobacterium ulcerans is a chronic necrotizing skin disease. It usually starts with a subcutaneous nodule or plaque containing large clusters of extracellular acid-fast bacilli. Surrounding tissue is destroyed by the cytotoxic macrolide toxin mycolactone produced by microcolonies of M. ulcerans. Skin covering the destroyed subcutaneous fat and soft tissue may eventually break down leading to the formation of large ulcers that progress, if untreated, over months and years. Here we have analyzed the bacterial flora of BU lesions of three different groups of patients before, during and after daily treatment with streptomycin and rifampicin for eight weeks (SR8) and determined drug resistance of the bacteria isolated from the lesions. Before SR8 treatment, more than 60% of the examined BU lesions were infected with other bacteria, with Staphylococcus aureus and Pseudomonas aeruginosa being the most prominent ones. During treatment, 65% of all lesions were still infected, mainly with P. aeruginosa. After completion of SR8 treatment, still more than 75% of lesions clinically suspected to be infected were microbiologically confirmed as infected, mainly with P. aeruginosa or Proteus miriabilis. Drug susceptibility tests revealed especially for S. aureus a high frequency of resistance to the first line drugs used in Ghana. Our results show that secondary infection of BU lesions is common. This could lead to delayed healing and should therefore be further investigated

Early Infant Diagnosis of HIV in Three Regions in Tanzania; Successes and Challenges.

By the end of 2009 an estimated 2.5 million children worldwide were living with HIV-1, mostly as a consequence of vertical transmission, and more than 90% of these children live in sub-Saharan Africa. In 2008 the World Health Organization (WHO), recommended early initiation of Highly Active Antiretroviral Therapy (HAART) to all HIV infected infants diagnosed within the first year of life, and since 2010, within the first two years of life, irrespective of CD4 count or WHO clinical stage. The study aims were to describe implementation of EID programs in three Tanzanian regions with differences in HIV prevalences and logistical set-up with regard to HIV DNA testing. Data were obtained by review of the prevention from mother to child transmission of HIV (PMTCT) registers from 2009-2011 at the Reproductive and Child Health Clinics (RCH) and from the databases from the Care and Treatment Clinics (CTC) in all the three regions; Kilimanjaro, Mbeya and Tanga. Statistical tests used were Poisson regression model and rank sum test. During the period of 2009 - 2011 a total of 4,860 exposed infants were registered from the reviewed sites, of whom 4,292 (88.3%) were screened for HIV infection. Overall proportion of tested infants in the three regions increased from 77.2% in 2009 to 97.8% in 2011. A total of 452 (10.5%) were found to be HIV infected (judged by the result of the first test). The prevalence of HIV infection among infants was higher in Mbeya when compared to Kilimanjaro region RR = 1.872 (95%CI = 1.408 - 2.543) p < 0.001. However sample turnaround time was significantly shorter in both Mbeya (2.7 weeks) and Tanga (5.0 weeks) as compared to Kilimanjaro (7.0 weeks), p=<0.001. A substantial of loss to follow-up (LTFU) was evident at all stages of EID services in the period of 2009 to 2011. Among the infants who were receiving treatment, 61% were found to be LFTU during the review period. The study showed an increase in testing of HIV exposed infants within the three years, there is large variations of HIV prevalence among the regions. Challenges like; sample turnaround time and LTFU must be overcome before this can translate into the intended goal of early initiation of lifelong lifesaving antiretroviral therapy for the infants

Focused Deterrence and the Prevention of Violent Gun Injuries: Practice, Theoretical Principles, and Scientific Evidence

Focused deterrence strategies are a relatively new addition to a growing portfolio of evidence-based violent gun injury prevention practices available to policy makers and practitioners. These strategies seek to change offender behavior by understanding the underlying violence-producing dynamics and conditions that sustain recurring violent gun injury problems and by implementing a blended strategy of law enforcement, community mobilization, and social service actions. Consistent with documented public health practice, the focused deterrence approach identifies underlying risk factors and causes of recurring violent gun injury problems, develops tailored responses to these underlying conditions, and measures the impact of implemented interventions. This article reviews the practice, theoretical principles, and evaluation evidence on focused deterrence strategies. Although more rigorous randomized studies are needed, the available empirical evidence suggests that these strategies generate noteworthy gun violence reduction impacts and should be part of a broader portfolio of violence prevention strategies available to policy makers and practitioners

IMPACTS OF PENSION REFORMS ON THE KENYAN PENSION INDUSTRY

The emergence of full-fledged reforms in Kenya from the introduction of the Retirement Benefits Authority in 1997 has rekindled hopes among the ageing population in Kenya. This paper examines the effect of the NSSF Act 2013 contribution rate by use of a contribution rate model as well as Kenyans’ perception towards the yet to be implemented Act by use of questionnaire analysis. The study asserts that the set 6% is sufficient to meet the welfare conditions of Kenyans. Further, this study also identifies the main social welfare reforms put in place, as well as the effects and challenges towards implementation of the reforms on the performance of the industry with a critical theoretical look at the NSSF Act 2013

IMPACTS OF PENSION REFORMS ON THE KENYAN PENSION INDUSTRY

The emergence of full-fledged reforms in Kenya from the introduction of the Retirement Benefits Authority in 1997 has rekindled hopes among the ageing population in Kenya. This paper examines the effect of the NSSF Act 2013 contribution rate by use of a contribution rate model as well as Kenyans’ perception towards the yet to be implemented Act by use of questionnaire analysis. The study asserts that the set 6% is sufficient to meet the welfare conditions of Kenyans. Further, this study also identifies the main social welfare reforms put in place, as well as the effects and challenges towards implementation of the reforms on the performance of the industry with a critical theoretical look at the NSSF Act 2013