143 research outputs found

    IQ and Family Background: Are Associations Strong or Weak?

    Get PDF
    For the purpose of understanding the underlying mechanisms behind intergenerational associations in income and education, recent studies have explored the intergenerational transmission of abilities. We use a large representative sample of Swedish men to examine both intergenerational and sibling correlations in IQ. Since siblings share both parental factors and neighbourhood influences, the sibling correlation is a broader measure of the importance of family background than the intergenerational correlation. We use IQ data from the Swedish military enlistment tests. The correlation in IQ between fathers (born 1951-1956) and sons (born 1966-1980) is estimated to 0.347. The corresponding estimate for brothers (born 1951-1968) is 0.473, suggesting that family background explains approximately 50% of a person's IQ. Estimating sibling correlations in IQ we thus find that family background has a substantially larger impact on IQ than has been indicated by previous studies examining only intergenerational correlations in IQ.ability, intergenerational mobility, family background

    Children of Unknown Fathers: Prevalence and Outcomes in Sweden

    Get PDF
    -Childhood conditions; family structure; child outcomes; father unknown

    Synthetic Metabolism: Engineering Biology at the Protein and Pathway Scales

    Get PDF
    Biocatalysis has become a powerful tool for the synthesis of high-value compounds, particularly so in the case of highly functionalized and/or stereoactive products. Nature has supplied thousands of enzymes and assembled them into numerous metabolic pathways. Although these native pathways can be use to produce natural bioproducts, there are many valuable and useful compounds that have no known natural biochemical route. Consequently, there is a need for both unnatural metabolic pathways and novel enzymatic activities upon which these pathways can be built. Here, we review the theoretical and experimental strategies for engineering synthetic metabolic pathways at the protein and pathway scales, and highlight the challenges that this subfield of synthetic biology currently faces.Synthetic Biology Engineering Research CenterNational Science Foundation (Grant no. 0540879

    Common Household Chemicals and the Allergy Risks in Pre-School Age Children

    Get PDF
    The risk of indoor exposure to volatile organic compounds (VOCs) on allergic airway diseases in children remains unknown.We examined the residential concentrations of VOCs, emitted from building materials, paints, furniture, and other lifestyle practices and the risks of multiple allergic diseases as well as the IgE-sensitization in pre-school age children in Sweden.In a case-control investigation (198 case children with asthma and allergy and 202 healthy controls), air samples were collected in the room where the child slept. The air samples were analyzed for the levels of eight classes of VOCs.A natural-log unit of summed propylene glycol and glycol ethers (PGEs) in bedroom air (equal to interquartile range, or 3.43 - 15.65 µg/m(3)) was associated with 1.5-fold greater likelihood of being a case (95% CI, 1.1 - 2.1), 1.5-fold greater likelihood of asthma (95% CI, 1.0 - 2.3), 2.8-fold greater likelihood of rhinitis (95% CI, 1.6 - 4.7), and 1.6-fold greater likelihood of eczema (95% CI, 1.1 - 2.3), accounting for gender, secondhand smoke, allergies in both parents, wet cleaning with chemical agents, construction period of the building, limonene, cat and dog allergens, butyl benzyl phthalate (BBzP), and di(2-ethylhexyl)phthalate (DEHP). When the analysis was restricted to the cases, the same unit concentration was associated with 1.8-fold greater likelihood of IgE-sensitization (95% CI, 1.1 - 2.8) compared to the non-IgE sensitized cases. No similar associations were found for the other classes of VOCs.We propose a novel hypothesis that PGEs in indoor air exacerbate and/or induce the multiple allergic symptoms, asthma, rhinitis and eczema, as well as IgE sensitization respectively

    Interventions to improve adherence to inhaled steroids for asthma.

    Get PDF
    BACKGROUND: Despite its proven efficacy in improving symptoms and reducing exacerbations, many patients with asthma are not fully adherent to their steroid inhaler. Suboptimal adherence leads to poorer clinical outcomes and increased health service utilisation, and has been identified as a contributing factor to a third of asthma deaths in the UK. Reasons for non-adherence vary, and a variety of interventions have been proposed to help people improve treatment adherence. OBJECTIVES: To assess the efficacy and safety of interventions intended to improve adherence to inhaled corticosteroids among people with asthma. SEARCH METHODS: We identified trials from the Cochrane Airways Trials Register, which contains studies identified through multiple electronic searches and handsearches of other sources. We also searched trial registries and reference lists of primary studies. We conducted the most recent searches on 18 November 2016. SELECTION CRITERIA: We included parallel and cluster randomised controlled trials of any duration conducted in any setting. We included studies reported as full-text articles, those published as abstracts only and unpublished data. We included trials of adults and children with asthma and a current prescription for an inhaled corticosteroid (ICS) (as monotherapy or in combination with a long-acting beta2-agonist (LABA)). Eligible trials compared an intervention primarily aimed at improving adherence to ICS versus usual care or an alternative intervention. DATA COLLECTION AND ANALYSIS: Two review authors screened the searches, extracted study characteristics and outcome data from included studies and assessed risk of bias. Primary outcomes were adherence to ICS, exacerbations requiring at least oral corticosteroids and asthma control. We graded results and presented evidence in 'Summary of findings' tables for each comparison.We analysed dichotomous data as odds ratios, and continuous data as mean differences or standardised mean differences, all using a random-effects model. We described skewed data narratively. We made no a priori assumptions about how trials would be categorised but conducted meta-analyses only if treatments, participants and the underlying clinical question were similar enough for pooling to make sense. MAIN RESULTS: We included 39 parallel randomised controlled trials (RCTs) involving adults and children with asthma, 28 of which (n = 16,303) contributed data to at least one meta-analysis. Follow-up ranged from two months to two years (median six months), and trials were conducted mainly in high-income countries. Most studies reported some measure of adherence to ICS and a variety of other outcomes such as quality of life and asthma control. Studies generally were at low or unclear risk of selection bias and at high risk of biases associated with blinding. We considered around half the studies to be at high risk for attrition bias and selective outcome reporting.We classified studies into four comparisons: adherence education versus control (20 studies); electronic trackers or reminders versus control (11 studies); simplified drug regimens versus usual drug regimens (four studies); and school-based directly observed therapy (three studies). Two studies are described separately.All pooled results for adherence education, electronic trackers or reminders and simplified regimens showed better adherence than controls. Analyses limited to studies using objective measures revealed that adherence education showed a benefit of 20 percentage points over control (95% confidence interval (CI) 7.52 to 32.74; five studies; low-quality evidence); electronic trackers or reminders led to better adherence of 19 percentage points (95% CI 14.47 to 25.26; six studies; moderate-quality evidence); and simplified regimens led to better adherence of 4 percentage points (95% CI 1.88 to 6.16; three studies; moderate-quality evidence). Our confidence in the evidence was reduced by risk of bias and inconsistency.Improvements in adherence were not consistently translated into observable benefit for clinical outcomes in our pooled analyses. None of the intervention types showed clear benefit for our primary clinical outcomes - exacerbations requiring an oral corticosteroid (OCS) (evidence of very low to low quality) and asthma control (evidence of low to moderate quality); nor for our secondary outcomes - unscheduled visits (evidence of very low to moderate quality) and quality of life (evidence of low to moderate quality). However, some individual studies reported observed benefits for OCS and use of healthcare services. Most school or work absence data were skewed and were difficult to interpret (evidence of low quality, when graded), and most studies did not specifically measure or report adverse events.Studies investigating the possible benefit of administering ICS at school did not measure adherence, exacerbations requiring OCS, asthma control or adverse events. One study showed fewer unscheduled visits, and another found no differences; data could not be combined. AUTHORS' CONCLUSIONS: Pooled results suggest that a variety of interventions can improve adherence. The clinical relevance of this improvement, highlighted by uncertain and inconsistent impact on clinical outcomes such as quality of life and asthma control, is less clear. We have low to moderate confidence in these findings owing to concerns about risk of bias and inconsistency. Future studies would benefit from predefining an evidence-based 'cut-off' for acceptable adherence and using objective adherence measures and validated tools and questionnaires. When possible, covert monitoring and some form of blinding or active control may help disentangle effects of the intervention from effects of inclusion in an adherence trial

    Self-care support for children and adolescents with long-term conditions : the REfOCUS evidence synthesis

    Get PDF
    Background: Self-care support (e.g. education, training, peer/professional support) is intended to enhance the self-care capacities of children and young people, while simultaneously reducing the financial burden facing health-care systems. Objectives: To determine which models of self-care support for long-term conditions (LTCs) are associated with significant reductions in health utilisation and costs without compromising outcomes for children and young people. Design: Systematic review with meta-analysis. Population: Children and young people aged 0–18 years with a long-term physical or mental health condition (e.g. asthma, depression). Intervention: Self-care support in health, social care, educational or community settings. Comparator: Usual care. Outcomes: Generic/health-related quality of life (QoL)/subjective health symptoms and health service utilisation/costs. Design: Randomised/non-randomised trials, controlled before-and-after studies, and interrupted time series designs. Data sources: MEDLINE, EMBASE, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, ISI Web of Science, NHS Economic Evaluation Database, The Cochrane Library, Health Technology Assessment database, Paediatric Economic Database Evaluation, IDEAS, reference scanning, targeted author searches and forward citation searching. All databases were searched from inception to March 2015. Methods: We conducted meta-analyses, simultaneously plotting QoL and health utilisation effects. We conducted subgroup analyses for evidence quality, age, LTC and intervention (setting, target, delivery format, intensity). Results: Ninety-seven studies reporting 114 interventions were included. Thirty-seven studies reported adequate allocation concealment. Fourteen were UK studies. The vast majority of included studies recruited children and young people with asthma (n = 66, 68%). Four per cent of studies evaluated ‘pure’ self-care support (delivered through health technology without additional contact), 23% evaluated facilitated self-care support (≤ 2 hours’/four sessions’ contact), 65% were intensively facilitated (≥ 2 hours’/four sessions’ contact) and 8% were case management (≥ 2 hours’ support with multidisciplinary input). Self-care support was associated with statistically significant, minimal benefits for QoL [effect size (ES) –0.17, 95% confidence interval (CI) –0.23 to –0.11], but lacked clear benefit for hospital admissions (ES –0.05, 95% CI –0.12 to 0.03). This finding endured across intervention intensities and LTCs. Statistically significant, minimal reductions in emergency use were observed (ES –0.11, 95% CI –0.17 to –0.04). The total cost analysis was limited by the small number of data. Subgroup analyses revealed statistically significant, minimal reductions in emergency use for children aged ≤ 13 years (ES –0.10, 95% CI –0.17 to –0.04), children and young people with asthma (ES –0.12, 95% CI –0.18 to –0.06) and children and young people receiving ≥ 2 hours per four sessions of support (ES –0.10, 95% CI –0.17 to –0.03). Preliminary evidence suggested that interventions that include the child or young person, and deliver some content individually, may optimise QoL effects. Face-to-face delivery may help to maximise emergency department effects. Caution is required in interpreting these findings. Limitations: Identification of optimal models of self-care support is challenged by the size and nature of evidence available. The emphasis on meta-analysis meant that a minority of studies with incomplete but potentially relevant data were excluded. Conclusions: Self-care support is associated with positive but minimal effects on children and young people’s QoL, and minimal, but potentially important, reductions in emergency use. On current evidence, we cannot reliably conclude that self-care support significantly reduces health-care costs. Future work: Research is needed to explore the short- and longer-term effects of self-care support across a wider range of LTCs. Study registration: This study is registered as PROSPERO CRD42014015452. Funding: The National Institute for Health Research Health Services and Delivery Research programme

    Many analysts, one data set: making transparent how variations in analytic choices affect results

    Get PDF
    Twenty-nine teams involving 61 analysts used the same data set to address the same research question: whether soccer referees are more likely to give red cards to dark-skin-toned players than to light-skin-toned players. Analytic approaches varied widely across the teams, and the estimated effect sizes ranged from 0.89 to 2.93 (Mdn = 1.31) in odds-ratio units. Twenty teams (69%) found a statistically significant positive effect, and 9 teams (31%) did not observe a significant relationship. Overall, the 29 different analyses used 21 unique combinations of covariates. Neither analysts’ prior beliefs about the effect of interest nor their level of expertise readily explained the variation in the outcomes of the analyses. Peer ratings of the quality of the analyses also did not account for the variability. These findings suggest that significant variation in the results of analyses of complex data may be difficult to avoid, even by experts with honest intentions. Crowdsourcing data analysis, a strategy in which numerous research teams are recruited to simultaneously investigate the same research question, makes transparent how defensible, yet subjective, analytic choices influence research results

    Early detection and counselling intervention of asthma symptoms in preschool children: study design of a cluster randomised controlled trial

    Get PDF
    Background. Prevention of childhood asthma is an important public health objective. This study evaluates the effectiveness of early detection of preschool children with asthma symptoms, followed by a counselling intervention at preventive child health centres. Early detection and counselling is expected to reduce the prevalence of asthma symptoms and improve health-related quality of life at age 6 years. Methods/design. This cluster randomised controlled trial was embedded within the Rotterdam population-based prospective cohort study Generation R in which 7893 children (born between April 2002 and January 2006) participated in the postnatal phase. Sixteen child health centres are involved, randomised into 8 intervention and 8 control centres. Since June 2005, an early detection tool has been applied at age 14, 24, 36 and 45 months at the intervention centres. Children who met the intervention criteria received counselling intervention (personal advice to parents to prevent smoke exposure of the child, and/or referral to the general practitioner or asthma nurse). The primary outcome was asthma diagnosis at age 6 years. Secondary outcomes included frequency and severity of asthma symptoms, health-related quality of life, fractional exhaled nitric oxide and airway resistance at age 6 years. Analysis was according to the intention-to-treat principle. Data collection will be completed end 2011. Discussion. This study among preschool children provides insight into the effectiveness of early detection of asthma symptoms followed by a counselling intervention at preventive child health centres. Trial registration. Current Controlled Trials ISRCTN15790308

    Fibrous clays based bionanocomposites

    Full text link
    • …
    corecore