Deviation Units (deviation + unit)

Distribution by Scientific Domains

Kinds of Deviation Units

  • standard deviation unit


  • Selected Abstracts


    Visceral fat is associated with lower brain volume in healthy middle-aged adults

    ANNALS OF NEUROLOGY, Issue 2 2010
    Stéphanie Debette MD
    Objective Midlife obesity has been associated with an increased risk of dementia. The underlying mechanisms are poorly understood. Our aim was to examine the cross-sectional association of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and computed tomography (CT)-based measurements of subcutaneous (SAT) and visceral (VAT) adipose tissue with various magnetic resonance imaging (MRI) markers of brain aging in middle-aged community adults. Methods Participants from the Framingham Offspring cohort were eligible if in addition to having measurements of BMI, WC, WHR, SAT, and VAT, they had undergone a volumetric brain MRI scan with measurements of total brain volume (TCBV), temporal horn volume (THV), white matter hyperintensity volume (WMHV), and MRI-defined brain infarcts (BI). All analyses were adjusted for age, sex, and time interval between abdominal CT and brain MRI. Results In a sample of 733 community participants (mean age, 60 years; 53% women), we observed an inverse association of BMI (estimate by standard deviation unit ± standard error = ,0.27 ± 0.12; p = 0.02), WC (,0.30 ± 0.12; p = 0.01), WHR (,0.37 ± 0.12; p = 0.02), SAT (,0.23 ± 0.11; p = 0.04), and VAT (,0.36 ± 0.12; p = 0.002) with TCBV, independent of vascular risk factors. The association between VAT and TCBV was the strongest and most robust, and was also independent of BMI (,0.35 ± 0.15; p = 0.02) and insulin resistance (,0.32 ± 0.13; p = 0.01). When adjusting for C-reactive protein levels, the associations were attenuated (,0.17 ± 0.13; p = 0.17 for VAT). No consistently significant association was observed between the anthropometric or CT-based abdominal fat measurements and THV, WMHV, or BI. Interpretation In middle-aged community participants, we observed a significant inverse association of anthropometric and CT-based measurements of abdominal, especially visceral, fat with total brain volume. ANN NEUROL 2010 [source]


    Enhancement of Farmland Biodiversity within Set-Aside Land

    CONSERVATION BIOLOGY, Issue 4 2004
    JOSH VAN BUSKIRK
    agricultura; biodiversidad; conservación; terrenos de reserva Abstract:,The efficacy of agricultural set-aside policies for protecting farmland biodiversity is widely debated. Based on a meta-analysis of 127 published studies, we found that land withdrawn from conventional production unequivocally enhances biodiversity in North America and Europe. The number of species of birds, insects, spiders, and plants is 1,1.5 standard deviation units higher on set-aside land, and population densities increase by 0.5,1 standard deviation units. Set-aside land may be especially beneficial for desirable taxa because North American bird species that have exhibited population declines react most positively to set-aside agricultural land. Larger and older plots protect more species and higher densities, and set-aside land is more effective in countries with less-intensive agricultural practices and higher fractions of land removed from production. Although policies specifically designed to protect biodiversity might work even better, current incentives clearly improve the standing of plants and animals in farmland. Resumen:,La eficiencia de las políticas de reservas agrícolas para la protección de la biodiversidad en tierras cultivadas esta ámpliamente debatida. Con base en un meta-análisis de 127 estudios publicados, encontramos que terrenos retirados de la producción convencional inequívocamente mejoran la biodiversidad en Norte América y Europa. El número de especies de aves, insectos, arañas y plantas es 1-1.5 unidades de desviación estándar más alto en terrenos de reserva, y las densidades de población incrementan en 0.5-1 unidades de desviación estándar. Los terrenos de reserva pueden ser especialmente benéficos para taxones deseables porque especies de aves norteamericanas que han presentado una declinación poblacional reaccionan positivamente a terrenos agrícolas de reserva. Parcelas más grandes y viejas protegen a más especies y tienen mayores densidades, y los terrenos de reserva son más efectivos en países con prácticas agrícolas menos intensivas y con mayores fracciones de tierras removidas de la producción. Aunque las políticas diseñadas específicamente para proteger la biodiversidad pueden ser mejores aún, los incentivos actuales claramente mejoran la situación de plantas y animales en tierras agrícolas. [source]


    Outcome of psychological treatments of pathological gambling: a review and meta-analysis

    ADDICTION, Issue 10 2005
    Ståle Pallesen
    ABSTRACT Aims To investigate the short- and long-term effect of psychological treatments of pathological gambling and factors relating to treatment outcome. Design and setting This study provides a quantitative meta-analytical review of psychotherapeutic treatments of pathological gambling. Studies were identified by computer search in the PsycINFO and Medline databases covering the period from 1966 to 2004, as well as from relevant reference lists. Inclusion criteria The target problem was pathological gambling, the treatment was psychological, the study was published in English and outcomes directly pertaining to gambling were employed. Single case studies, studies where elimination of gambling not was the priority and studies with insufficient statistical information were excluded from the present meta-analysis. Participants A total of 37 outcome studies, published or reported between 1968 and 2004, were identified. Of these 15 were excluded, thus 22 studies were included, involving 1434 subjects. The grand mean age was 40.1 years. The overall proportion of men was 71.5%. Measurements The included studies were coded for outcome measures of pathological gambling. For each condition, means and standard deviations for gambling-related outcome measures, all based upon self-reports or therapist ratings, were compiled at three points in time: baseline, post-treatment and the last follow-up reported. Findings Effect sizes represent the difference between the mean score in a treatment condition and a control condition or the difference between mean scores at separated points in time for one group, expressed in terms of standard deviation units. At post-treatment the analysis indicated that psychological treatments were more effective than no treatment, yielding an overall effect size of 2.01 (P < 0.01). At follow-up (averaging 17.0 months) the corresponding effect size was 1.59 (P < 0.01). A multiple regression analysis showed that the magnitude of effect sizes at post-treatment were lower in studies including patients with a formal diagnosis of pathological gambling only, compared to studies not employing such inclusion criteria. Effect sizes were also higher in randomized controlled trials compared to not randomized controlled trials, higher in within subjects designs compared to between subjects designs and also positively related to number of therapy sessions. No mediator variables were significantly related to the magnitude of the effect sizes at follow-up. Conclusion Psychological interventions for pathological gamble seem to be yield very favourable short- and long-term outcomes. [source]


    Differences Between Self-Adapted and Computerized Adaptive Tests: A Meta-Analysis

    JOURNAL OF EDUCATIONAL MEASUREMENT, Issue 3 2001
    Angela K. Pitkin
    Self-adapted testing has been described as a variation of computerized adaptive testing that reduces test anxiety and thereby enhances test performance. The purpose of this study was to gain a better understanding of these proposed effects of self-adapted tests (SATs); meta-analysis procedures were used to estimate differences between SATs and computerized adaptive tests (CATs) in proficiency estimates and post-test anxiety levels across studies in which these two types of tests have been compared. After controlling for measurement error, the results showed that SATs yielded proficiency estimates that were 0.12 standard deviation units higher and post-test anxiety levels that were 0.19 standard deviation units lower than those yielded by CATs. We speculate about possible reasons for these differences and discuss advantages and disadvantages of using SATs in operational settings. [source]


    Genetic mapping of quantitative trait loci for resistance to Haemonchus contortus in sheep

    ANIMAL GENETICS, Issue 3 2009
    K. Marshall
    Summary This paper presents results from a mapping experiment to detect quantitative trait loci (QTL) for resistance to Haemonchus contortus infestation in merino sheep. The primary trait analysed was faecal worm egg count in response to artificial challenge at 6 months of age. In the first stage of the experiment, whole genome linkage analysis was used for broad-scale mapping. The animal resource used was a designed flock comprising 571 individuals from four half-sib families. The average marker spacing was about 20 cM. For the primary trait, 11 QTL (as chromosomal/family combinations) were significant at the 5% chromosome-wide level, with allelic substitution effects of between 0.19 and 0.38 phenotypic standard deviation units. In general, these QTL did not have a significant effect on faecal worm egg count recorded at 13 months of age. In the second stage of the experiment, three promising regions (located on chromosomes 1, 3 and 4) were fine-mapped. This involved typing more closely spaced markers on individuals from the designed flock as well as an additional 495 individuals selected from a related population with a deeper pedigree. Analysis was performed using a linkage disequilibrium,linkage approach, under additive, dominant and multiple QTL models. Of these, the multiple QTL model resulted in the most refined QTL positions, with resolutions of <10 cM achieved for two regions. Because of the moderate size of effect of the QTL, and the apparent age and/or immune status specificity of the QTL, it is suggested that a panel of QTL will be required for significant genetic gains to be achieved within industry via marker-assisted selection. [source]