There is a large body of research reporting high rates of psychotic disorders among many migrant and minority ethnic groups, particularly in Northern Europe. In the context of increasing migration and consequent cultural diversity in many places worldwide, these findings are a major social and public health concern. In this paper, we take stock of the current state of the art, reviewing evidence on variations in rates of psychoses and putative explanations, including relevant theories and models. We discuss in particular: a) the wide variation in reported rates of psychotic disorders by ethnic group, and b) the evidence implicating social risks to explain this variation, at ecological and individual levels. We go on to set out our proposed socio-developmental model, that posits greater exposure to systemic social risks over the life course, particularly those involving threat, hostility and violence, to explain high rates of psychoses in some migrant and minority ethnic groups. Based on this analysis, the challenge of addressing this social and public health issue needs to be met at multiple levels, including social policy, community initiatives, and mental health service reform.

10children, among others.Studies assessing the associations between BP and objectively-measured PA are very limited in children during the first decade of life. One cross-sectional study found no association between BP and objectively-measured PA in a sample of 3-to 6-year-old children. 7 However, the duration of PA measurement in this study was short (24 hours) and may not reflect habitual PA. Several longitudinal studies have Abstract-High blood pressure (BP) is becoming increasingly common during childhood. Regular physical activity (PA) reduces BP in adults, but limited studies have reported inconsistent results among children. The aim of this study is to examine, for the first time, the cross-sectional and longitudinal associations between BP and objectively measured PA in young children of predominantly South Asian background. Data from the Birmingham healthy Eating and Active lifestyle for CHildren Study were analyzed. Five hundred seventy-four children, aged 5 to 7 years, underwent a series of measures at baseline and were followed up 2 years later. PA was objectively measured using accelerometry and converted to counts per minute (total PA, cpm), and time spent in moderate-vigorous PA (minutes per day). BP was measured by trained staff using standard protocols. Data were available for 512 children at baseline (mean age 6.5 years, range 5.4-7.8 years), and 427 of these children were followed up. Baseline total PA was inversely associated with diastolic BP at both baseline (adjusted regression coefficient Knowles et al Physical Activity and Blood Pressure in Children 71found inverse associations between subjective measures of PA and BP in adolescents, 15,17 but data are lacking for primary school aged children. To our knowledge, no study to date has examined longitudinal associations between BP and objectively-measured PA in prepubertal children. Furthermore, there are few published data on children of South Asian origin, despite lower PA levels and increased cardiovascular risk in this ethnic group when compared with their white British and African-Caribbean counterparts. 19,20 In the present study, we therefore aimed to explore the cross-sectional and longitudinal associations between BP and objectively-measured PA in a cohort of UK primary school children with a high proportion of South Asians, to inform future interventions. Methods Subjects and Study DesignData were available on 574 children (51.7% male, 86% South Asian, 5-7 years old at baseline) who were recruited for the Birmingham healthy Eating and Active lifestyle for CHildren Study (BEACHeS). This exploratory trial was set up to develop and test a childhood obesity prevention intervention that was culturally appropriate to the South Asian community but inclusive of all children. South Asian groups, which comprise one fifth of the population in Birmingham, are at increased risk of obesity and related comorbidities 19,20 ; hence the focus on developing a culturally appropriate intervention for this ethnic group. Using ethnicity data obtained ...