7 research outputs found
Partner bereavement and risk of chronic urticaria, alopecia areata and vitiligo:cohort studies in the UK and Denmark
The pathogeneses of skin diseases are not fully understood. Psychological stress has been proposed to be associated with skin diseases, but the epidemiological evidence is limited [1, 2]. We have recently reported the associations between partner bereavement (an extreme life stressor) and psoriasis, atopic eczema and melanoma [3, 4]. In this study, we further investigated whether partner bereavement was associated with urticaria, alopecia areata, or vitiligo
Missing at random assumption made more plausible:evidence from the 1958 British birth cohort
ABSTRACT Objective : Non-response is unavoidable in longitudinal surveys. The consequences are lower statistical power and the potential for bias. We implemented a systematic data-driven approach to identify predictors of non-response in the National Child Development Study (NCDS; 1958 British birth cohort). Such variables can help make the missing at random assumption more plausible, which has implications for the handling of missing data Study Design and Setting : We identified predictors of non-response using data from the 11 sweeps (birth to age 55) of the NCDS (nâŻ=âŻ17,415), employing parametric regressions and the LASSO for variable selection. Results : Disadvantaged socio-economic background in childhood, worse mental health and lower cognitive ability in early life, and lack of civic and social participation in adulthood were consistently associated with non-response. Using this information, along with other data from NCDS, we were able to replicate the âpopulation distributionâ of educational attainment and marital status (derived from external data), and the original distributions of key early life characteristics. Conclusion : The identified predictors of non-response have the potential to improve the plausibility of the missing at random assumption. They can be straightforwardly used as âauxiliary variablesâ in analyses with principled methods to reduce bias due to missing data
Antenatal blood pressure for prediction of pre-eclampsia, preterm birth, and small for gestational age babies: developmental and validation in two general population cohorts
Study questionCan routine antenatal blood pressure measurements between 20 and 36 weeksâ gestation contribute to the prediction of pre-eclampsia and its associated adverse outcomes?MethodsThis study used repeated antenatal measurements of blood pressure from 12?996 women in the Avon Longitudinal Study of Parents and Children (ALSPAC) to develop prediction models and validated these in 3005 women from the Southampton Womenâs Survey (SWS). A model based on maternal early pregnancy characteristics only (BMI, height, age, parity, smoking, existing and previous gestational hypertension and diabetes, and ethnicity) plus initial mean arterial pressure was compared with a model additionally including current mean arterial pressure, a model including the deviation of current mean arterial pressure from a stratified normogram, and a model including both at different gestational ages from 20-36 weeks.Study answer and limitationsThe addition of blood pressure measurements from 28 weeks onwards improved prediction models compared with use of early pregnancy risk factors alone, but they contributed little to the prediction of preterm birth or small for gestational age. Though multiple imputation of missing data was used to increase the sample size and minimise selection bias, the validation sample might have been slightly underpowered as the number of cases of pre-eclampsia was just below the recommended 100. Several risk factors were self reported, potentially introducing measurement error, but this reflects how information would be obtained in clinical practice.What this study adds The addition of routinely collected blood pressure measurements from 28 weeks onwards improves predictive models for pre-eclampsia based on blood pressure in early pregnancy and other characteristics, facilitating a reduction in scheduled antenatal care.Funding, competing interests, data sharingUK Wellcome Trust, US National Institutes of Health, and UK Medical Research Council. Other funding sources for authors are detailed in the full online paper. With the exceptions of CM-W, HMI, and KMG there were no competing interests
Partner bereavement and risk of psoriasis and atopic eczema: cohort studies in the U.K. and Denmark
Additional file 1: of Investigating the importance of the local food environment for fruit and vegetable intake in older men and women in 20 UK towns: a cross-sectional analysis of two national cohorts using novel methods
STROBE-nut: an extension of the STROBE statement for nutritional epidemiology. (DOCX 100ĂÂ kb
Processing and Properties of a Microcellular Foam System with Low Sensitivity to Temperature
Measurement of the production cross section in pp collisions at 7 TeV using the kinematic properties of events with leptons and jets
This is the Pre-Print version of the Article. The official published version can be accessed from the link below - Copyright @ 2011 Springer VerlagA measurement of the top-antitop production cross section in proton-proton collisions at a centre-of-mass energy of 7 TeV has been performed at the LHC with the CMS detector. The analysis uses a data sample corresponding to an integrated luminosity of 36 inverse picobarns and is based on the reconstruction of the final state with one isolated, high transverse-momentum electron or muon and three or more hadronic jets. The kinematic properties of the events are used to separate the top-antitop signal from W+jets and QCD multijet background events. The measured cross section is 173 + 39 - 32 (stat. + syst.) pb, consistent with standard model expectations