INTRODUCTION Literature on the age at first anal intercourse (AFAI) among men who have sex with men (MSM) is limited. We aimed to elucidate the evolution of AFAI and the factors associated with early AFAI, based on a large sample of MSM in China. METHODS We collected information on the demographics and sexual behaviours of MSM from seven large cities in China from 2012 to 2013. Blood samples ...

OBJECTIVE We report here the influence of sleep patterns on the development of infants in Japan. A total of 479 infants were registered in two different Japanese cities. Direct neurological observations were performed by licensed pediatric neurologists. METHOD We designed a prospective cohort study and identified the sleep factors of children showing atypical development. The Kinder Infant De...

BACKGROUND The demographics of doctors working in the UK are changing. The United Kingdom (UK) has voted to leave the European Union (EU) and there is heightened political discourse around the world about the impact of migration on healthcare services. Previous work suggests that foreign trained doctors perform worse than UK graduates in postgraduate medical examinations. We analysed the preval...

Although the case-control or the cross-sectional design has been popular in genetic association studies of human longevity, such a design is prone to false positive results due to sampling bias and a potential secular trend in gene-environment interactions. To avoid these problems, the cohort or follow-up study design has been recommended. With the observed individual survival information, the ...

OBJECTIVE To date, no study has prospectively examined the association between social capital (SC) in the community and oral health. The aim of this longitudinal cohort study was to examine the association between both community-level and individual-level SC and tooth loss in older Japanese people. DESIGN Prospective cohort study SETTING We utilised data from the Japan Gerontological Evalua...

BACKGROUND The relationship between neuroticism, depression and cardiovascular disease (CVD) is complex and has so far not been studied in depth. The aim of this study was to determine if neuroticism is an effect-modifier in the association between depression and CVD. Data derived from a longitudinal cohort study on mental health, work and relations among adults (20-64 years), including 10,443 ...

The aim of this study was to describe the incidence of metabolic syndrome and to identify five components as metabolic syndrome predictors. The final study included 1,095 subjects enrolled in a rural part of Daegu Metropolitan City, Korea for a cohort study in 2003. Of these, 762 (69.6%) subjects had participated in the repeat survey. During the five-year follow-up, incidence density was signif...

BACKGROUND Hemoglobin C trait, like hemoglobin S trait, protects against severe malaria in children, but it is unclear whether hemoglobin C trait also protects against uncomplicated malaria. We hypothesized that Malian children with hemoglobin C trait would have a lower risk of clinical malaria than children with hemoglobin AA. METHODS Three hundred children aged 0-6 years were enrolled in a ...

BACKGROUND Long-term multicentre studies are subject to numerous factors that may affect the integrity of their conclusions. Quality control and standardization of data collection are crucial to minimise the biases induced by these factors. Nevertheless, tools implemented to manage biases are rarely described in publications about population-based cohorts. This report aims to describe the proce...

PRIMARY STUDY OBJECTIVE To evaluate the economic utility of a fecal biomarker panel structured to suggest alternative, treatable diagnoses in patients with symptoms of irritable bowel syndrome (IBS) by quantifying, comparing, and contrasting health service costs between tested and non-tested patients. STUDY DESIGN Retrospective, matched cohort study comparing direct medical costs for IBS pati...