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Stronger Evidence (stronger + evidence)
Selected AbstractsMapping quantitative effects of oligogenes by allelic associationANNALS OF HUMAN GENETICS, Issue 3 2002W. ZHANG Regression analysis of a quantitative trait as a function of a single diallelic polymorphism has been extended to allelic association by composite likelihood under the Malecot model for multiple markers. We applied the method to 10 single nucleotide polymorphisms (SNPs) spanning 27 kb of the angiotensin-I converting enzyme (ACE) gene in British families, localising a causal SNP between G2530A and 4656(CT)3/2 in the 3, region, at a distance of 21.6±0.9 kb from the most proximal SNP T-5491C. Neither they nor the I/D polymorphism is causal. To clarify genetic parameters we applied combined segregation, linkage and association analysis. Stronger evidence for the 3, region was obtained, with significant evidence of a lesser 5, effect as reported in French and Nigerian families. However, rigorous confirmation requires that the causal SNPs be identified. Both Malecot and parametric analysis appear to have high power by comparison with alternative methods for localizing oligogenes and their causal polymorphisms. [source] Does smoking cue-induced craving tell us anything important about nicotine dependence?ADDICTION, Issue 10 2009Kenneth A. Perkins ABSTRACT Cue-reactivity, or self-reported craving response to drug-associated stimuli, is an active area of research on factors that maintain drug use, particularly cigarette smoking. A common rationale for this research is the expectation that treatments that extinguish cue-induced craving will be effective as smoking cessation interventions. Therefore, the importance of research on the variables that moderate and control cue-induced craving would seem to hinge upon the relevance of cue-induced craving to nicotine dependence, particularly its association with relapse risk. However, the limited relevant clinical research has not demonstrated clearly a link between smoking relapse risk and self-reported craving in response to smoking cues. Links between relapse and other responses to cues, such as heart rate or electrodermal activity, are inconsistent or not significant. The Food and Drug Administration (FDA)-approved smoking cessation medications have not been shown to alleviate cue-induced craving, although they do alleviate abstinence-induced craving, which has been associated with relapse risk. Nevertheless, other acute measures assessed in the laboratory have been shown to predict subsequent relapse risk in quitting smokers, demonstrating the feasibility of this type of study. Future research may benefit from using more reliable and valid multi-item craving measures, focusing upon more specific conditions under which cue-induced craving may predict relapse and, most importantly, considering dependent measures other than self-reported craving in response to cues, particularly actual smoking behavior. Without stronger evidence in support of the relevance of cue-induced craving response to the persistence of smoking behavior or other measures of dependence, it will be incumbent upon researchers in this area to justify why studies of cue-induced craving contribute to our understanding of dependence. [source] AAN-EFNS guidelines on trigeminal neuralgia managementEUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2008G. Cruccu Several issues regarding diagnosis, pharmacological treatment, and surgical treatment of trigeminal neuralgia (TN) are still unsettled. The American Academy of Neurology and the European Federation of Neurological Societies launched a joint Task Force to prepare general guidelines for the management of this condition. After systematic review of the literature the Task Force came to a series of evidence-based recommendations. In patients with TN MRI may be considered to identify patients with structural causes. The presence of trigeminal sensory deficits, bilateral involvement, and abnormal trigeminal reflexes should be considered useful to disclose symptomatic TN, whereas younger age of onset, involvement of the first division, unresponsiveness to treatment and abnormal trigeminal evoked potentials are not useful in distinguishing symptomatic from classic TN. Carbamazepine (stronger evidence) or oxcarbazepine (better tolerability) should be offered as first-line treatment for pain control. For patients with TN refractory to medical therapy early surgical therapy may be considered. Gasserian ganglion percutaneous techniques, gamma knife and microvascular decompression may be considered. Microvascular decompression may be considered over other surgical techniques to provide the longest duration of pain freedom. The role of surgery versus pharmacotherapy in the management of TN in patients with multiple sclerosis remains uncertain. [source] Assessment of Family Functioning in Caucasian and Hispanic Americans: Reliability, Validity, and Factor Structure of the Family Assessment DeviceFAMILY PROCESS, Issue 4 2007GREGORY A. AARONS PH.D. The purpose of this study was to examine the factor structure, reliability, and validity of the Family Assessment Device (FAD) among a national sample of Caucasian and Hispanic American families receiving public sector mental health services. A confirmatory factor analysis conducted to test model fit yielded equivocal findings. With few exceptions, indices of model fit, reliability, and validity were poorer for Hispanic Americans compared with Caucasian Americans. Contrary to our expectation, an exploratory factor analysis did not result in a better fitting model of family functioning. Without stronger evidence supporting a reformulation of the FAD, we recommend against such a course of action. Findings highlight the need for additional research on the role of culture in measurement of family functioning. [source] Genetic association with rheumatoid arthritis,Genetic Analysis Workshop 15: summary of contributions from Group 2GENETIC EPIDEMIOLOGY, Issue S1 2007Marsha A. Wilcox Abstract The papers in presentation group 2 of Genetic Analysis Workshop 15 (GAW15) conducted association analyses of rheumatoid arthritis data. The analyses were carried out primarily in the data provided by the North American Rheumatoid Arthritis Consortium (NARAC). One group conducted analyses in the data provided by the Canadian Rheumatoid Arthritis Genetics Study (CRAGS). Analysis strategies included genome-wide scans, the examination of candidate genes, and investigations of a region of interest on chromosome 18q21. Most authors employed relatively new methods, proposed extensions of existing methods, or introduced completely novel methods for aspects of association analysis. There were several common observations; a group of papers using a variety of methods found stronger association, on chromosomes 6 and 18 and in candidate gene PTPN22 among women with early onset. Generally, models that considered haplotypes or multiple markers showed stronger evidence for association than did single marker analyses. Genet. Epidemiol. 31 (Suppl. 1):S12,S21, 2007. © 2007 Wiley-Liss, Inc. [source] Testing association between disease and multiple SNPs in a candidate geneGENETIC EPIDEMIOLOGY, Issue 5 2007W. James Gauderman Abstract Current technology allows investigators to obtain genotypes at multiple single nucleotide polymorphism (SNPs) within a candidate locus. Many approaches have been developed for using such data in a test of association with disease, ranging from genotype-based to haplotype-based tests. We develop a new approach that involves two basic steps. In the first step, we use principal components (PCs) analysis to compute combinations of SNPs that capture the underlying correlation structure within the locus. The second step uses the PCs directly in a test of disease association. The PC approach captures linkage-disequilibrium information within a candidate region, but does not require the difficult computing implicit in a haplotype analysis. We demonstrate by simulation that the PC approach is typically as or more powerful than both genotype- and haplotype-based approaches. We also analyze association between respiratory symptoms in children and four SNPs in the Glutathione-S-Transferase P1 locus, based on data from the Children's Health Study. We observe stronger evidence of an association using the PC approach (p = 0.044) than using either a genotype-based (p = 0.13) or haplotype-based (p = 0.052) approach. Genet. Epidemiol. 2007. © 2007 Wiley-Liss, Inc. [source] Genetics of the apnea hypopnea index in Caucasians and African Americans: I. Segregation analysisGENETIC EPIDEMIOLOGY, Issue 3 2002Sarah G. Buxbaum Abstract Differences in age of presentation and anatomic risk factors for obstructive sleep apnea (OSA) in Caucasians and African Americans suggest possible racial differences in the genetic underpinnings of the disorder. In this study, we assess transmission patterns in a Caucasian sample consisting of 177 families (N = 1,195) and in an African American sample consisting of 125 families (N = 720) for two variables: 1) apnea hypopnea index (AHI) log transformed and adjusted for age, and 2) AHI log transformed and adjusted for age and body mass index (BMI). We allowed for residual familial correlations and sex-specific means in all models. Analysis of the Caucasian sample showed transmission patterns consistent with that of a major gene that were stronger in the age-adjusted variable than in the age- and BMI-adjusted variable. However, in the African American families, adjusting for BMI in addition to age gave stronger evidence for segregation of a codominant gene with an allele frequency of 0.14, accounting for 35% of the total variance. These results provide support for an underlying genetic basis for OSA that in African Americans is independent of the contribution of BMI. Genet. Epidemiol. 22:243,253, 2002. © 2002 Wiley-Liss, Inc. [source] Forging Democracy at GunpointINTERNATIONAL STUDIES QUARTERLY, Issue 3 2006JEFFREY PICKERING Can liberal interventionism build liberal democracy? This manuscript examines the military interventions undertaken by the U.S., U.K., France, and the UN in the post-World War II era to see if they had a positive impact on democracy in target countries. Empirical analysis centers on multivariate time series, cross section PCSE and relogit regressions of political liberalization and democratization from 1946 to 1996. The former is operationalized with annual difference data drawn from the Polity IV data collection, whereas the latter is a binary variable denoting countries that cross a threshold commonly used to indicate the establishment of democratic institutions. An updated version of the International Military Intervention data set enumerates foreign military interventions. We find little evidence that military intervention by liberal states helps to foster democracy in target countries. Although a few states have democratized in the wake of hostile U.S. military interventions, the small number of cases involved makes it difficult to draw generalizable conclusions from the U.S. record. We find stronger evidence, however, that supportive interventions by the UN's "Blue Helmets" can help to democratize target states. [source] A Reexamination of the Tradeoff between the Future Benefit and Riskiness of R&D IncreasesJOURNAL OF ACCOUNTING RESEARCH, Issue 1 2008ALLAN EBERHART ABSTRACT Many previous studies document a positive relation between research and development (R&D) and equity value. Though R&D can increase equity value by increasing firm value, it can also increase equity value at the expense of bondholder wealth through an increase in firm risk because equity is analogous to a call option on the underlying firm value. Shi [2003] tests this hypothesis by examining the relation between a firm's R&D intensity and its bond ratings and risk premiums at issuance. His results show that the net effect of R&D is negative for bondholders. We reexamine Shi's [2003] findings and in so doing make three contributions to the literature. First, we find that Shi's [2003] results are sensitive to the method of measuring R&D intensity. When we use what we argue is a better measure of R&D intensity, we find that the net effect of R&D is positive for bondholders. Second, when we use tests that Shi [2003] recognizes are even better than the ones that he uses, we find even stronger evidence of the positive effect of R&D on bondholders. Third, we examine cross-sectional differences in the effect of R&D on debtholders. Consistent with our main finding, we document a negative relation between R&D increases and default risk. The default risk reduction is also more pronounced for firms with higher initial default scores (where the debtholders have more to gain from an R&D increase) and for firms with more bank debt (where the debtholders have greater covenant protection from the possible detriments associated with R&D increases). [source] More on the effectiveness of public spending on health care and education: a covariance structure modelJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 6 2003Emanuele Baldacci Using data for a sample of developing countries and transition economies, this paper estimates the relationship between government spending on health care and education and selected social indicators. Unlike previous studies, where social indicators are used as proxies for the unobservable health and education status of the population, this paper estimates a latent variable model. The findings suggest that public spending is an important determinant of social outcomes, particularly in the education sector. Overall, the latent variable approach yields better estimates of a social production function than the traditional approach, with higher elasticities of social indicators with respect to income and spending, therefore providing stronger evidence that increases in public spending do have a positive impact on social outcomes. Copyright © 2003 John Wiley & Sons, Ltd. [source] Non-target impacts of poison baiting for predator control in AustraliaMAMMAL REVIEW, Issue 3 2007A. S. GLEN ABSTRACT 1Mammalian predators are controlled by poison baiting in many parts of the world, often to alleviate their impacts on agriculture or the environment. Although predator control can have substantial benefits, the poisons used may also be potentially harmful to other wildlife. 2Impacts on non-target species must be minimized, but can be difficult to predict or quantify. Species and individuals vary in their sensitivity to toxins and their propensity to consume poison baits, while populations vary in their resilience. Wildlife populations can accrue benefits from predator control, which outweigh the occasional deaths of non-target animals. We review recent advances in Australia, providing a framework for assessing non-target effects of poisoning operations and for developing techniques to minimize such effects. We also emphasize that weak or circumstantial evidence of non-target effects can be misleading. 3Weak evidence that poison baiting presents a potential risk to non-target species comes from measuring the sensitivity of species to the toxin in the laboratory. More convincing evidence may be obtained by quantifying susceptibility in the field. This requires detailed information on the propensity of animals to locate and consume poison baits, as well as the likelihood of mortality if baits are consumed. Still stronger evidence may be obtained if predator baiting causes non-target mortality in the field (with toxin detected by post-mortem examination). Conclusive proof of a negative impact on populations of non-target species can be obtained only if any observed non-target mortality is followed by sustained reductions in population density. 4Such proof is difficult to obtain and the possibility of a population-level impact cannot be reliably confirmed or dismissed without rigorous trials. In the absence of conclusive evidence, wildlife managers should adopt a precautionary approach which seeks to minimize potential risk to non-target individuals, while clarifying population-level effects through continued research. [source] The ,ghosts' that pester studies on learning in mosquitoes: guidelines to chase them offMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2006W. J. ALONSO Abstract The identification of memory and learning in medically important mosquito species has been of epidemiological interest mainly because of the implications of learning on the pattern of contact between vectors and hosts. Empirical results either showing or suggesting the existence of cognitive abilities in mosquitoes have been reported in a number of experimental studies, mainly based on the observation of individual fidelity towards subsets of specific resources, such as hosts, resting sites or breeding sites. A closer inspection of the design of these experiments shows that, with the exception of recent studies providing stronger evidence of learning in the genus Culex (Diptera: Culicidae), methodological shortcomings still hinder the possibility of eliminating alternative interpretations for these findings, in some cases because the experiments were not specifically designed to identify the phenomenon, but mostly because of a lack of appropriate controls or replication. By highlighting these limitations, while acknowledging the practical difficulties that are inherent to the field, we aim to help expel from future research the ,ghosts' that still preclude the achievement of more definite conclusions about the prevalence of memory and learning in this group of insects. [source] Host-driven divergence in the parasitic plant Orobanche minor Sm. (Orobanchaceae)MOLECULAR ECOLOGY, Issue 19 2008C. J. THOROGOOD Abstract Many parasitic angiosperms have a broad host range and are therefore considered to be host generalists. Orobanche minor is a nonphotosynthetic root parasite that attacks a range of hosts from taxonomically disparate families. In the present study, we show that O. minor sensu lato may comprise distinct, genetically divergent races isolated by the different ecologies of their hosts. Using a three-pronged approach, we tested the hypothesis that intraspecific taxa O. minor var. minor and O. minor ssp. maritima parasitizing either clover (Trifolium pratense) or sea carrot (Daucus carota ssp. gummifer), respectively, are in allopatric isolation. Morphometric analysis revealed evidence of divergence but this was insufficient to define discrete, host-specific taxa. Intersimple sequence repeat (ISSR) marker-based data provided stronger evidence of divergence, suggesting that populations were isolated from gene flow. Phylogenetic analysis, using sequence-characterized amplified region (SCAR) markers derived from ISSR loci, provided strong evidence for divergence by clearly differentiating sea carrot-specific clades and mixed-host clades. Low levels of intrapopulation SCAR marker sequence variation and floral morphology suggest that populations on different hosts are probably selfing and inbreeding. Morphologically cryptic Orobanche taxa may therefore be isolated from gene flow by host ecology. Together, these data suggest that host specificity may be an important driver of allopatric speciation in parasitic plants. [source] Combining paternally and maternally inherited mitochondrial DNA for analysis of population structure in musselsMOLECULAR ECOLOGY, Issue 6 2004Robert A. Krebs Abstract Sequence divergence for a fragment of the 16S rRNA gene was compared to identify the advantages in using mitochondrial genes that descend separately through the female and male lineages to examine population structure. The test compared divergence among four local species of freshwater mussels (Unionidae) and was extended to multiple populations of one species, Pyganodon grandis. For the same gene, the male-inherited sequences diverged at a faster rate, producing longer branch lengths in the phylogenies. Of particular use were sequences extracted from P. grandis populations from the southern region of the Lake Erie watershed (Ohio, USA); five male-inherited haplotypes were found. Only one change was observed in the female-inherited form in this region. Therefore, more rapid evolution has occurred in the male form of the gene, and this form provided stronger evidence of geographical isolation among populations. A combination of analyses on haplotypes derived through males and females creates complementary opportunities to identify evolutionary relationships caused by drift and migration in mussels. [source] Breastfeeding as obesity prevention in the United States: A sibling difference modelAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Molly W. Metzger In light of the growing prevalence of obesity in the United States, and the health risks associated with childhood obesity in particular, it is critical to identify avenues for obesity prevention. This study tests the hypothesis that breastfeeding serves as one protective factor against children's subsequent development of obesity. We used linear-, logistic-, and sibling fixed-effects regression models to evaluate the association between infant feeding history and body mass index (BMI) in late childhood or adolescence (9,19 years, mean = 14 years). Complete data were available for 976 participants (488 sibling pairs) in the 2002 Child Development Supplement of the Panel Study of Income Dynamics, a nationally representative survey of families in the United States. In sibling pairs in which only one sibling was breastfed, the breastfed sibling had an adolescent BMI that was 0.39 standard deviations lower than his or her sibling, controlling for child-specific factors that may have influenced parents' feeding decisions. This effect is equivalent to a difference of more than 13 pounds for a 14-year-old child of average height. Furthermore, fixed-effects logistic regressions predicting overweight and obese status showed that breastfed siblings were less likely to reach those BMI thresholds. We therefore conclude that breastfeeding in infancy may be an important protective factor against the development of obesity in the United States. The application of a sibling fixed-effects model provides stronger evidence of a causal relationship than prior research reporting similar patterns of association. Am. J. Hum. Biol. 2010. © 2009 Wiley-Liss, Inc. [source] Risk factors for work-related musculoskeletal disorders: a systematic review of recent longitudinal studiesAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2010Bruno R. da Costa PT Abstract Objective This systematic review was designed and conducted in an effort to evaluate the evidence currently available for the many suggested risk factors for work-related musculoskeletal disorders. Methods To identify pertinent literature we searched four electronic databases (Cinahl, Embase, Medline, and The Cochrane Library). The search strategies combined terms for musculoskeletal disorders, work, and risk factors. Only case,control or cohort studies were included. Results A total of 1,761 non-duplicated articles were identified and screened, and 63 studies were reviewed and integrated in this article. The risk factors identified for the development of work-related musculoskeletal disorders were divided and organized according to the affected body part, type of risk factor (biomechanical, psychosocial, or individual) and level of evidence (strong, reasonable, or insufficient evidence). Conclusions Risk factors with at least reasonable evidence of a causal relationship for the development of work-related musculoskeletal disorders include: heavy physical work, smoking, high body mass index, high psychosocial work demands, and the presence of co-morbidities. The most commonly reported biomechanical risk factors with at least reasonable evidence for causing WMSD include excessive repetition, awkward postures, and heavy lifting. Additional high methodological quality studies are needed to further understand and provide stronger evidence of the causal relationship between risk factors and work-related musculoskeletal disorders. The information provided in this article may be useful to healthcare providers, researchers, and ergonomists interested on risk identification and design of interventions to reduce the rates of work-related musculoskeletal disorders. Am. J. Ind. Med. 53:285,323, 2010. © 2009 Wiley-Liss, Inc. [source] Challenges for donor agency country-level performance assessment: a review,PUBLIC ADMINISTRATION & DEVELOPMENT, Issue 5 2003Mark Ireland This review of country-level performance assessment in donor agencies is primarily based upon the experiences documented by bilateral donors to developing countries. The review suggests that four emerging themes can be identified in the literature on country-level performance review: ownership, decentralisation and leadership, accountability and learning and complexity. The review considers the implementation of ,results-based' approaches used by a number of international agencies and examines their relationship with ,evidence-based' approaches. A key challenge, in the development of performance assessment, is bringing in a stronger evidence-based approach into the planning and evaluation of donor country-level programmes. Copyright © 2003 John Wiley & Sons, Ltd. [source] GENDER DISCRIMINATION, INTRAHOUSEHOLD RESOURCE ALLOCATION, AND IMPORTANCE OF SPOUSES' FATHERS: EVIDENCE ON HOUSEHOLD EXPENDITURE FROM RURAL INDIATHE DEVELOPING ECONOMIES, Issue 4 2006Nobuhiko FUWA D12; D13; D63; D64 Data collected from rural India was used to examine the rules governing intrahousehold resource allocations. Testing for gender-age discrimination among household members using Deaton's (1989) method, results suggest a general bias favoring boys over girls in allocation of consumption goods, however, the findings are not always statistically significant. Intrahousehold resource allocation rules are then examined to see if such discrimination is based on the unanimous decision of parents. The novelty in our test on allocation rule are: (1) use of grandparental variables as extra-household environmental parameters (EEPs) in expenditure estimation, (2) derivation of a test of the unitary model that only requires EEPs, and (3) semi-formal use of survival status of grandparents in testing collective models. It is interesting that spouse's father characteristics are importantly correlated with greater mother and child goods expenditure shares, and smaller father goods shares. Their survival status matters, and this is stronger evidence for a collective as opposed to unitary model. [source] I,Varieties of Support and Confirmation of Climate ModelsARISTOTELIAN SOCIETY SUPPLEMENTARY VOLUME, Issue 1 2009Elisabeth A. Lloyd Today's climate models are supported in a couple of ways that receive little attention from philosophers or climate scientists. In addition to standard ,model fit', wherein a model's simulation is compared to observational data, there is an additional type of confirmation available through the variety of instances of model fit. When a model performs well at fitting first one variable and then another, the probability of the model under some standard confirmation function, say, likelihood, goes up more than under each individual case of fit alone. Thus, two instances of fit of distinct variables of a global climate model using distinct data sets considered collectively will provide stronger evidence for a model than either one of the instances considered individually. This has consequences for model robustness. Sets of models that produce robust results will, if their assumptions vary enough and they each are observationally sound, provide reasons to endorse common structures found in those models. Finally, independent empirical support for aspects and assumptions of the model provides an additional confirmational virtue for climate models, contrary to what is implied by some current philosophical writing on this topic. [source] A long-term record of Nothofagus dominance in the southern Andes, ChileAUSTRAL ECOLOGY, Issue 1 2005William Pollmann Abstract The general model of regeneration dynamics in Nothofagus forests of southern South America could have value in community ecology if predictive relationships between disturbance history, functional traits and site attributes could be identified. Examined here is the proposal that on favourable sites shade-intolerant Nothofagus are likely not to survive in competition with shade-tolerant, broad-leaved evergreen taxa of temperate rain forests, and persistence, thus, is dependent on periodic coarse-scale disturbance. Comparison of stand dynamics of three old-growth Nothofagus forests at different elevations in the southern Andes, Chile where deciduous Nothofagus alpina dominates the upper canopy, and examination of the life history trade-offs of this variation were made. Stem density of all stems ,5.0 cm d.b.h. was 233,303 stems per hectare, and basal area was 123.9,171.0 m2ha,1. Maximum lifespan of N. alpina was found to be greater than ca 640 years, exceeding all previously reported ages for this species in the region. Forests had a stable canopy composition for this long-term, but some appeared to lack effective regeneration of N. alpina in recent years. Regeneration of N. alpina was generally greater in disturbed stands and higher elevation than in undisturbed stands and at lower elevation. Recruitment emerged to be strongly affected by competitive over- and understorey associates. There was a gradient of increasing dependence of N. alpina on disturbance towards the more productive end of the environment gradients, and hence less dependence of N. alpina on disturbance for its regeneration towards higher elevation. The study confirms that changes in forest composition may be explained by processes occurring in accordance with the predictions of the existing model of Nothofagus regeneration dynamics, providing stronger evidence specifically directed at mid-tolerant N. alpina, and by factoring out regeneration dynamics on favourable sites. Thus, for N. alpina, trait differences probably contribute to the competitive advantage over its associates in productive habitats, and may be linked to small-to-intermediate-sized disturbances which inevitably occur as older trees die, enabling N. alpina to persist in forests and therefore maintain species coexistence for the long-term. [source] | ||||||||||||||||||||||||||||