bluuebunny/crossref_metadata_2025_split huggingface dataset:
OP72 Prospective External Validation of Risk Prediction Models for Acute Traumatic Brain Injury in UK Critical Care Units: The Rain Study
Authors: Harrison DA , Griggs KA , Gomes M , Menon DK , Rowan KM 
Published: September 2012

BackgroundAcute traumatic brain injury (TBI) is the leading cause of death and disability in adults aged under 40 years. Statistical models have been developed to predict the risk of mortality or unfavourable outcome (death or severe disability) at six months following acute TBI but to date these risk prediction models have only been validated using existing data sources. The Risk Adjustment In Neurocritical care (RAIN) Study aimed to validate these risk prediction models among adults with acute TBI admitted to UK critical care units.MethodsTen risk prediction models were identified: four for mortality at six months (the Hukkelhoven model and IMPACT Core, Extended and Lab models); and six for unfavourable outcome at six months (as mortality plus CRASH Basic and CT models). Risk factor data were collected from 67 UK critical care units (including 90% of regional neuroscience centres) from August 2009 to March 2011. Patients were followed up to six months for mortality by linkage with death registration and unfavourable outcome using the Glasgow Outcome Scale (Extended) administered by postal or telephone questionnaire.The risk prediction models were validated for calibration (c index), discrimination (Hosmer-Lemeshow test and Cox calibration regression) and overall fit (Brier score). Missing data were handled with multiple imputation.ResultsData were collected for 2,975 eligible patients admitted to critical care following acute TBI. 97% of patients were followed-up for mortality and 81% for unfavourable outcome at six months. Following multiple imputation, mortality and unfavourable outcome at six months were 26% and 57%, respectively. Risk prediction models for mortality at six months had good discrimination (c index 0.75–0.78) and the Hukkelhoven and IMPACT Lab models were well calibrated, although the IMPACT Core and Extended models over-predicted mortality. The models for unfavourable outcome at six months had worse discrimination (c index 0.69–0.71) and all models substantially under-predicted risk of unfavourable outcome. The best performance overall was found for the IMPACT Lab model, which was the most complex model, incorporating laboratory measurements. Models of the next level of complexity (Hukkelhoven, CRASH CT, IMPACT Extended) all performed similarly.ConclusionRisk prediction models for acute TBI had acceptable discrimination among a large, representative sample of patients admitted to UK critical care units. Calibration was good for mortality but poor for unfavourable outcome, and these models therefore require recalibration for use in this setting.
OP76 Households and Health: How Small Clusters Can Influence Results
Authors: Leyland AH , Gray L 
Published: September 2012

BackgroundThere have been studies suggesting that various measures of health, health behaviours or health seeking cluster within households. Previous research on the impact of omitting small clusters from analyses have suggested little impact on parameter estimates or standard errors but have typically assumed small intraclass correlations – not usually the case for the household. Since there are typically few individuals per household, and many households contain just one person, several studies have excluded household from the analysis. We examine what difference it makes in practice when the level of household is excluded for a variety of outcomes.Methods7901 adults from 5063 households in 356 small areas were interviewed in the 2003 Scottish Health Survey; in 2512 (49.6%) of households just one adult participated. We analysed systolic blood pressure (SBP), BMI, current smoking status, eating 5+ portions of fruit and vegetables per day, eating oily fish at least once per week, and having seen a GP within the past 2 weeks. All results were adjusted for age and sex; in addition, we examined the effects of education, social class and area deprivation. Interactions were fitted between sex and all terms in the fixed and random parts of the model. Multiple imputation was used to account for item non-response. Multilevel linear and logistic regression models including and excluding household were fitted by Markov chain Monte Carlo and the results compared, with population average estimates obtained for logistic regression models.ResultsThe extent of clustering varied by outcome and gender; the proportion of the total unexplained variance at the household level ranged from 8.6% (95% Credible interval 0.3–24.5) for systolic blood pressure for women to 87.5% (83.7–90.7) for eating oily fish for women. Bias was evident in both the fixed parameter estimates and their standard errors. The bias in the fixed parameters tended to be higher for outcomes for which the household variance was higher.ConclusionFor all outcomes the inclusion of household provided an improvement in model fit. Excluding the level of household led to biases not just in the standard errors but also in the parameter estimates themselves. This has implications not only regarding the need to account for clustering within households but also regarding the use of “sandwich estimators” that adjust the standard error but not the regression coefficient.
OP80 Minimum Unit Pricing for Alcohol: A Document Analysis of Evidence Submissions to the Scottish Parliament
Authors: Katikireddi S V , Hilton S , Bond L 
Published: September 2012

BackgroundMinimum unit pricing (MUP) of alcohol is a novel policy intervention aimed at increasing the price of the cheapest forms of alcohol to reduce alcohol consumption and associated harms. In Scotland, alcohol-related harms have increased exponentially during the past few decades and Scotland currently experiences the greatest level of alcohol-related mortality within the UK. Scotland would be the first country in the world to introduce the measure and therefore both advocates and critics have seized the opportunity to put forward the different arguments in the case of MUP. This study examines the evidence submitted to the Scottish Parliament with the aim of examining how arguments for and against MUP have been framed and to consider what forms of evidence have been drawn upon by different policy stakeholders to debate MUP.MethodsThe Scottish Parliament received evidence submissions from a wide variety of stakeholders in its first consideration of MUP as part of the Stage 1 scrutiny process for the Alcohol (etc.) Bill 2010. Sixty-five documents submitted by 47 different stakeholders (including politicians, health professionals, industry representatives, supermarkets and researchers) considered within meetings of the Select Committee were analysed. Data management was assisted using Nvivo 9, framework matrices, and thematically analysed using constant comparative methods.ResultsArguments around alcohol policy have been actively constructed as a health issue by advocates for MUP in comparison to critics who highlight economic, ideological, and social aspects. Constructions of alcohol overconsumption as a population health issue, rather than an individual-level health problem, were contested. Alcohol epidemiology was drawn upon by advocates (to support a whole population approach) but also by critics (to argue alcohol harms are reducing). Issues raised in opposition include important potential secondary impacts such as exacerbating inequalities, increasing cross-border and illicit trade and perverse incentives (such as increases in profitability driving retailers to encourage increased sales).ConclusionFraming of alcohol policy as a health (rather than, for example, trade or justice) issue that requires a whole population approach has been important in creating conditions amenable to MUP being seriously considered by policymakers. The initial framing of an issue in different ways can lead to similar sources of evidence, such as routine epidemiological data, being used to suggest different actions are appropriate. Public health researchers and practitioners should be aware of the active construction process occurring in policy definition and adapt research and advocacy accordingly.
OP81 Estimating the Potential of Population Level Changes in Cholesterol and Blood Pressure for Reducing UK Coronary Heart Disease Mortality Rates: A Novel Modelling Approach
Authors: O’Flaherty M , Couch P , Sperrin M , Green N , Ainsworth J , Huffmann M , Lloyd-Jones D , Buchan I , Capewell S 
Published: September 2012

BackgroundCoronary heart disease (CHD) mortality is declining. However, population ageing and increasing obesity and diabetes might reverse this trend. Strategies to reduce salt and saturated fat intake could substantially decrease population-wide cholesterol and blood pressure levels and consequently reduce CHD events. Our aim was to explore the potential reduction in CHD mortality burden that might be achieved by population shifts in these risk factors.MethodsThe novel Stock of Health (SoH) modelling approach integrates demographic and risk factor data from the Office for National Statistics and the Health Survey for England, and risk factor effects from the US Cardiovascular Lifetime Risk Pooling Project. The SoH approach estimates the latent “stock” of CHD-related health for each individual within the entire population of England and Wales (51 million). It then computes failure times for CHD mortality, allowing for multiplicative risk factor effects and competing mortality risks.We first simulated CHD deaths for England and Wales over the period 2000-2010. We then extended the simulations to 2030, and compared “FEASIBLE” and “IDEAL” population intervention scenarios, targeted to systolic blood pressure (SBP) and cholesterol under two future trend assumptions: I) assuming mortality rates in 2010 remain stable through to 2030, or II) assuming CHD mortality continue falling.ResultsThe mean simulated failure times closely mirrored those actually observed(1993–2004: men=72 vs. 71 years; women=74 vs. 75 years). In 2030, about 81200 CHD deaths are expected to occur under trend assumption I (+14% compared to 2010, reflecting population ageing) and 47600 under trend assumption II (–18% compared to 2010). SBP: For trend I, a FEASIBLE SBP reduction of 1mmHg and IDEAL reduction of –5mmHg could result in approximately 77300 (+9%, baseline: 2010)and 64500 (–9%, baseline: 2010) deaths respectively in 2030. Assuming falling trends (II), about 45500 (–22%, baseline: 2010) and 38300 (–34%, baseline: 2010) deaths would result in 2030 under the feasible and ideal scenarios respectively. Total cholesterol (TC): Under trend I, a FEASIBLE TC reduction of 0.1 mmol/l and IDEAL reduction of 0.5 mmol/l could result in about 74800 and 57000 deaths (5% and –20%) by 2030. Assuming trend II, the resulting deaths would be approximately 43900 and 33400 (–25% and –43%, baseline: 2010) respectively.ConclusionUnder both trend assumptions, the adoption of evidence-based dietary policies to reduce salt and saturated fat intake, resulting in population-wide decreases in blood pressure and cholesterol could result in substantial declines in forecasted CHD mortality.
OP87 Healthy Behaviours in Middle Age and Long-Term Consequences for Mortality, Physical and Cognitive Function, and Mental Health
Authors: Lang IA , Goodwin V , Hubbard R , Llewellyn DJ 
Published: September 2012

BackgroundPhysical activity, healthy body weight, smoking, and alcohol consumption are each related to mortality, physical and cognitive function, and mental health but their combined long-term effect is unknown. We examined the individual and combined influence of these risk factors on mortality and subjective and measured function in middle-aged adults followed for 18 years.MethodsData were from the US Health and Retirement Study (HRS), a biennial, longitudinal, nationally representative survey of older adults. 11,597 participants aged 51 to 61 were followed from study enrolment for an 18-year period. A health behaviour score was calculated with one point for each behaviour: moderate physical activity three times per week; BMI 20 to 25; alcohol consumption less than 7 drinks/week; non-smoking. Outcomes were all-cause mortality, problems with activities of daily living (ADLs), lung function, grip strength, walk speed, measured cognitive function, and depressive symptoms. Adjusted logistic and linear regression models were used to examine the relationships between health behaviours and outcomes separately by gender.ResultsFor all outcomes except grip strength there was a dose-response relationship between healthy behaviour score and outcomes. For example, in men with four healthy behaviours and no baseline ADL problems, at 18-year follow-up 78.4% had no ADL problems, 6.6% had ADL problems, and 15.0% had died. In men with no healthy behaviours and no ADL problems at baseline, at follow-up 35.1% had no ADL problems, 8.8% had ADL problems, and 56.1% had died. Results in women were comparable but ADL differences were more marked. Number of healthy behaviours was related to follow-up cognitive function, mental health, walk speed, and lung function but not grip strength. Results were robust to adjustment for socioeconomic status (SES: measures of health, income, and level of education) and in analyses stratified by SES similar differences were found in relation to healthy behaviours within strata.ConclusionSimple differences in lifestyle behaviours in middle age are associated with major differences in mortality, functioning and health risks as people progress into old age. Effective health promotion in these age groups could bring substantial health benefits for individuals across SES groups.
OP89 The Association of Parental Fatal and Non-Fatal Suicidal Behaviour with Offspring Suicidalbehaviourand Depression: A Systematic Review and Meta-Analysis
Authors: Geulayov G , Gunnell DJ , Holmen TL , Metcalfe C 
Published: September 2012

BackgroundChildren whose parents die by, or attempt, suicide are believed to be at greater risk of suicidal behaviours and affective disorders. We systematically reviewed the literature on the association of parental fatal and non-fatal suicidal behaviours with offspring suicidal behaviour and depression and, using meta-analysis, estimated the strength of these associations. We further investigated the role of parental and offspring gender, and offspring age at exposure as potential effect modifiers.MethodsWe carried out a comprehensive literature search using Medline (1950-April 2011), PsycINFO (1876-April 2011), EMBASE (1980-April 2011) and Web of Science. Twenty eight articles met our inclusion criteria, 14 of which contributed to the meta-analysis. Crude odds ratio (OR) and adjusted odds ratio (AOR) were pooled using fixed-effects models.ResultsControlling for relevant confounders, offspring whose parents died by suicide were more likely than offspring of two living parents to die by suicide [AOR 1.94, 95% confidence interval (CI) 1.54–2.45] but there were heterogeneous findings in the two studies investigating the impact of parental suicide on offspring suicide attempt (AOR 1.31, 95% CI 0.73–2.35). Children whose parents attempted suicide were more likely than unexposed children to attempt suicide (AOR 1.95, 95% CI 1.48–2.57). However, compared with offspring of parents who died by other causes, the risk of suicidal behaviour was only slightly elevated for offspring of suicide decedents (suicide: OR 1. 81, 95% CI 1.56–2.10; suicide attempt: OR 1.73, 95% CI 1.63–1.83); no adjusted analyses were available. Limited published research indicated that offspring exposure to parental death by suicide is associated with subsequent increased risk of affective disorders compared to offspring of two living parents. Maternal suicidal behaviour was associated with larger effect estimates compared to paternal suicidal behaviours. There was some evidence that younger age at exposure to parental suicidal behaviours was associated with greater risk than exposure in later childhood/adolescence. There was no evidence that the association differed in sons versus daughters.ConclusionParental suicidal behaviour is associated with increased risk of offspring suicidal behaviour, above and beyond the risk associated with a loss of a parent to a cause other than suicide. Findings suggest that maternal suicidal behaviour is a more potent risk factor than paternal suicidal behaviour. Limited evidence suggests that children are more vulnerable than adolescents and adults. However, there is no evidence of a stronger association in either male or female offspring.
OP90 Evaluating Mental Wellbeing in Children with Health Related Barriers to Learning: Results of a Quasi-Experimental before and after Intervention
Authors: Putz RE , Clarke A 
Published: September 2012

BackgroundClear associations have been demonstrated between poor mental health, behavioural problems and low educational attainment in secondary school children while negative self-perceptions are associated with truancy and classroom disruption at secondary school level. The majority of research in this field focuses and measures outcomes in terms of mental illness. Fewer interventions have been evaluated using positive mental health/mental wellbeing measures, though the body of evidence is growing.We aimed to evaluate the effect of targeted school counselling or ‘Wellbeing Mentorship’ on mental wellbeing in children with health related barriers to learning at risk of low educational attainment and attendance. Health related barriers to learning included medical issues, mental health, sexual health, bullying, family challenges and emotional and behavioural barriers.MethodsThe Warwick Edinburgh Mental Wellbeing Scale (WEMWBS) was used to evaluate mental wellbeing in pupils seen by Wellbeing Mentors. WEMWBS is validated for use in populations aged 13+. Gender, age, school deprivation, attainment and attendance were measured. Mentors at eight diverse schools collected data from April 2011 to February 2012. A power analysis was conducted. Given the risk of high attrition, pupils were sampled within a designated time frame wherein Mentors evaluated every eligible pupil. Pupils completed WEMWBS at the beginning, end, and 6–10 weeks after their last mentoring session. Interventions comprised 6 sessions of weekly one-to-one health and wellbeing support.ResultsNinety-six eligible pupils undertook and completed WEMWBS, out of 160 estimated mentoring referrals. Using paired t-tests and ANOVA, we assessed changes in WEMWBS scores between time points. Pupils’ mental wellbeing significantly improved (95% Confidence) from baseline to completion. Girls’ baseline mean WEMWBS score (43.3) increased by 7.4 points to 50.7 at completion; boys baseline mean (44.2) increased by 6.2 to 50.4. These changes were sustained at follow up. Boys and girls results demonstrate statistically and clinically meaningful change. We compared our results with WEMWBS data collected in 2008 from two of the same and one similar school (n=753). The comparator mean for girls (47.4) and boys (49.8) indicate that mentored pupils improved their mental wellbeing to a similar level (boys) or a significantly higher level (girls).Cooperation, process measures, attainment and attendance reporting varied greatly between schools; these data are still being collected.ConclusionBoth before and after and population controls suggest that mentoring is a worthwhile intervention for improving mental wellbeing in secondary school pupils identified with health related barriers to learning.
OP92 The Impact of Military Deployment, Combat Experiences and Post-Deployment Mental Health Problems on Violent Behaviour among UK Military Personnel
Authors: MacManus D , Dean K , Jones M , Rona R , Hull L , Greenberg N , Fahy T , Wessely S , Fear N 
Published: September 2012

BackgroundThere is considerable media, political and public interest on both sides of the Atlantic in an alleged rise in violence among military personnel returned from conflicts in Iraq and Afghanistan. This study explores violence among a large sample of UK military personnel, a proportion of whom had been deployed to Iraq/Afghanistan. The aims were to estimate the prevalence of self-reported violence, examine the impact of deployment and combat experiences on subsequent violence and the association with post-deployment mental health problems and alcohol misuse.MethodsThis study formed part of a questionnaire-based cohort study established to explore the impact of deployment on mental health among UK military personnel. The sample was randomly selected from all military personnel serving in the UK Armed Forces between 2003 and 2007. A total of 9986 participants from all Services were included, some had been deployed and some had been trained but not deployed. Special Forces were excluded. Data, collected by questionnaire, included information on deployment experiences, socio-demographic and military characteristics, pre-enlistment antisocial behaviour, and post-deployment health outcomes. The main violence outcomes were self –report measures of interpersonal violence.Results6.2% of the sample reported interpersonal violence in the last month. Deployment showed a stronger association with subsequent violence among reservists (OR=2.98 (1.50–5.93),P=0.002) than among regulars (OR=1.26 (0.96–1.67),P=0.098) when compared to their non-deployed counterparts. Performing a combat role whilst deployed was associated with a significantly increased likelihood of violence among regulars (OR=1.90 (1.38–2.75), P<0.001) and the risk of violence increased with the number of traumatic events experienced (P<0.001)). Violence on homecoming was also associated with mental health problems such as PTSD (OR=4.8 (3.2–7.2) P<0.001) and alcohol misuse (OR=3.1 (2.5–3.9) P<0.001).ConclusionMilitary deployment, in particular combat exposure, increased the risk of subsequent violence among military personnel and the risk of violence increased with increasing number of traumatic events experienced on deployment. Valuable information on risk factors for violence among military personnel is provided, especially regarding increased risk among deployed reservists and among personnel who report post-deployment mental health problems and alcohol misuse.