8,312 research outputs found

    Quantitative systematic review of the associations between short-term exposure to nitrogen dioxide and mortality and hospital admissions.

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    BACKGROUND: Short-term exposure to NO₂ has been associated with adverse health effects and there is increasing concern that NO₂ is causally related to health effects, not merely a marker of traffic-generated pollution. No comprehensive meta-analysis of the time-series evidence on NO₂ has been published since 2007. OBJECTIVE: To quantitatively assess the evidence from epidemiological time-series studies published worldwide to determine whether and to what extent short-term exposure to NO₂ is associated with increased numbers of daily deaths and hospital admissions. DESIGN: We conducted a quantitative systematic review of 204 time-series studies of NO₂ and daily mortality and hospital admissions for several diagnoses and ages, which were indexed in three bibliographic databases up to May 2011. We calculated random-effects estimates by different geographic regions and globally, and also tested for heterogeneity and small study bias. RESULTS: Sufficient estimates for meta-analysis were available for 43 cause-specific and age-specific combinations of mortality or hospital admissions (25 for 24 h NO₂ and 18 of the same combinations for 1 h measures). For the all-age group, a 10 µg/m(3) increase in 24 h NO₂ was associated with increases in all-cause, cardiovascular and respiratory mortality (0.71% (95% CI 0.43% to 1.00%), 0.88% (0.63% to 1.13%) and 1.09% (0.75% to 1.42%), respectively), and with hospital admissions for respiratory (0.57% (0.33% to 0.82%)) and cardiovascular (0.66% (0.32% to 1.01%)) diseases. Evidence of heterogeneity between geographical region-specific estimates was identified in more than half of the combinations analysed. CONCLUSIONS: Our review provides clear evidence of health effects associated with short-term exposure to NO₂ although further work is required to understand reasons for the regional heterogeneity observed. The growing literature, incorporating large multicentre studies and new evidence from less well-studied regions of the world, supports further quantitative review to assess the independence of NO₂ health effects from other air pollutants

    An accurate test for homogeneity of odds ratios based on Cochran's Q-statistic

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    Background: A frequently used statistic for testing homogeneity in a meta-analysis of K independent studies is Cochran's Q. For a standard test of homogeneity the Q statistic is referred to a chi-square distribution with K - 1 degrees of freedom. For the situation in which the effects of the studies are logarithms of odds ratios, the chi-square distribution is much too conservative for moderate size studies, although it may be asymptotically correct as the individual studies become large. Methods: Using a mixture of theoretical results and simulations, we provide formulas to estimate the shape and scale parameters of a gamma distribution to t the distribution of Q. Results: Simulation studies show that the gamma distribution is a good approximation to the distribution for Q. Conclusions: : Use of the gamma distribution instead of the chi-square distribution for Q should eliminate inaccurate inferences in assessing homogeneity in a meta-analysis. (A computer program for implementing this test is provided.) This hypothesis test is competitive with the Breslow-Day test both in accuracy of level and in power

    Caregiver Integration During Discharge Planning for Older Adults to Reduce Resource Use: A Metaanalysis

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    Objectives To determine the effect of integrating informal caregivers into discharge planning on postdischarge cost and resource use in older adults. Design A systematic review and metaanalysis of randomized controlled trials that examine the effect of discharge planning with caregiver integration begun before discharge on healthcare cost and resource use outcomes. MEDLINE, EMBASE, and the Cochrane Library databases were searched for all English‐language articles published between 1990 and April 2016. Setting Hospital or skilled nursing facility. Participants Older adults with informal caregivers discharged to a community setting. Measurements Readmission rates, length of and time to post‐discharge rehospitalizations, costs of postdischarge care. Results Of 10,715 abstracts identified, 15 studies met the inclusion criteria. Eleven studies provided sufficient detail to calculate readmission rates for treatment and control participants. Discharge planning interventions with caregiver integration were associated with a 25% fewer readmissions at 90 days (relative risk (RR) = 0.75, 95% confidence interval (CI) = 0.62–0.91) and 24% fewer readmissions at 180 days (RR = 0.76, 95% CI = 0.64–0.90). The majority of studies reported statistically significant shorter time to readmission, shorter rehospitalization, and lower costs of postdischarge care among discharge planning interventions with caregiver integration. Conclusion For older adults discharged to a community setting, the integration of caregivers into the discharge planning process reduces the risk of hospital readmission

    Pain relief for women with cervical intraepithelial neoplasia undergoing colposcopy treatment

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    Treatment for CIN is usually undertaken in an outpatient colposcopy clinic to remove the pre-cancerous cells from the cervix. It commonly involves lifting the cells off the cervix with electrically heated wire (diathermy) or laser, or destroying the abnormal cells with freezing methods (cryotherapy). This is potentially a painful procedure. The purpose of this review is to determine which, if any, pain relief should be used during cervical colposcopy treatment. We identified 17 trials and these reported different forms of pain relief before, during and after colposcopy. Evidence from two small trials showed that women having a colposcopy treatment had less pain and blood loss if the cervix was injected with a combination of a local anaesthetic drug and a drug that causes blood vessels to constrict (narrow), compared with placebo. Although taking oral pain-relieving drugs (e.g. ibuprofen) before treatment on the cervix in the colposcopy clinic is recommended by most guidelines, evidence from two small trials did not show that this practice reduced pain during the procedure. Most of the evidence in this field is of a low to moderate quality and further research may change these findings. Additionally, we were unable to obtain evidence with regards to dosage of the local anaesthetic drug or method of administering local anaesthetic into the cervix. There is need for high-quality trials with sufficient numbers of participants in order to provide the data necessary to estimate these effects

    Consensus and meta-analysis regulatory networks for combining multiple microarray gene expression datasets

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    Microarray data is a key source of experimental data for modelling gene regulatory interactions from expression levels. With the rapid increase of publicly available microarray data comes the opportunity to produce regulatory network models based on multiple datasets. Such models are potentially more robust with greater confidence, and place less reliance on a single dataset. However, combining datasets directly can be difficult as experiments are often conducted on different microarray platforms, and in different laboratories leading to inherent biases in the data that are not always removed through pre-processing such as normalisation. In this paper we compare two frameworks for combining microarray datasets to model regulatory networks: pre- and post-learning aggregation. In pre-learning approaches, such as using simple scale-normalisation prior to the concatenation of datasets, a model is learnt from a combined dataset, whilst in post-learning aggregation individual models are learnt from each dataset and the models are combined. We present two novel approaches for post-learning aggregation, each based on aggregating high-level features of Bayesian network models that have been generated from different microarray expression datasets. Meta-analysis Bayesian networks are based on combining statistical confidences attached to network edges whilst Consensus Bayesian networks identify consistent network features across all datasets. We apply both approaches to multiple datasets from synthetic and real (Escherichia coli and yeast) networks and demonstrate that both methods can improve on networks learnt from a single dataset or an aggregated dataset formed using a standard scale-normalisation

    Systematic review of the agreement of tonometers with goldmann applanation tonometry

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    This review was part of the Surveillance for Ocular Hypertension study funded by the UK National Institute for Health Research Health Technology Assessment Programme (Project No. 07/46/02). J.C. held a Medical Research Council UK fellowship (G0601938). AA-B was a grantholder on an AstraZeneca (London, UK) funded study of a new medication for glaucoma. The Health Services Research Unit receives core funding from the Chief Scientist Office of the Scottish Government Health Directorates. Views and opinions expressed are those of the authors and do not necessarily reflect those of the Chief Scientist Office, National Institute for Health Research Health Technology Assessment Programme, or the Department of Health. None of the funders had a role in the design or conduct of this researchPeer reviewedPostprin

    From a mouse: systematic analysis reveals limitations of experiments testing interventions in Alzheimer's disease mouse models

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    The increasing prevalence of Alzheimer's disease (AD) poses a considerable socio-economic challenge. Decades of experimental research have not led to the development of effective disease modifying interventions. A deeper understanding of in vivo research might provide insights to inform future in vivo research and clinical trial design. We therefore performed a systematic review and meta-analysis of interventions tested in transgenic mouse models of AD. We searched electronically for publications testing interventions in transgenic models of AD. We extracted data for outcome, study characteristics and reported study quality and calculated summary estimates of efficacy using random effects meta-analysis. We identified 427 publications describing 357 interventions in 55 transgenic models, involving 11,118 animals in 838 experiments. Of concern, reported study quality was relatively low; fewer than one in four publications reported the blinded assessment of outcome or random allocation to group and no study reported a sample size calculation. Additionally, there were few data for any individual intervention-only 16 interventions had outcomes described in 5 or more publications. Finally, "trim and fill" analyses suggested one in seven pathological and neurobehavioural experiments remain unpublished. Given these historical weaknesses in the in vivo modelling of AD in transgenic animals and the identified risks of bias, clinical trials that are based on claims of efficacy in animals should only proceed after a detailed critical appraisal of those animal data

    The Grizzly, March 15, 2018

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    Ursinus Evacuates Main Street Houses as Winter Storm Cuts Collegeville Power • Blomberg Hires New Special Assistant • Student Government Holds Elections This Week • SASA to Host Philly Lion Dancers • Clybourne Park Comes to Ursinus • Opinions: Diversity Monologues Reflect Lack of Racial Diversity; Students Should Use Art as a Form of Political Protest • Softball Wins Seven Straight in Florida • Champions: Women\u27s Swimming 5-peatshttps://digitalcommons.ursinus.edu/grizzlynews/1640/thumbnail.jp
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