732 research outputs found

    The value of source data verification in a cancer clinical trial

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    Background Source data verification (SDV) is a resource intensive method of quality assurance frequently used in clinical trials. There is no empirical evidence to suggest that SDV would impact on comparative treatment effect results from a clinical trial. Methods Data discrepancies and comparative treatment effects obtained following 100% SDV were compared to those based on data without SDV. Overall survival (OS) and Progression-free survival (PFS) were compared using Kaplan-Meier curves, log-rank tests and Cox models. Tumour response classifications and comparative treatment Odds Ratios (ORs) for the outcome objective response rate, and number of Serious Adverse Events (SAEs) were compared. OS estimates based on SDV data were compared against estimates obtained from centrally monitored data. Findings Data discrepancies were identified between different monitoring procedures for the majority of variables examined, with some variation in discrepancy rates. There were no systematic patterns to discrepancies and their impact was negligible on OS, the primary outcome of the trial (HR (95% CI): 1.18(0.99 to 1.41), p = 0.064 with 100% SDV; 1.18(0.99 to 1.42), p = 0.068 without SDV; 1.18(0.99 to 1.40), p = 0.073 with central monitoring). Results were similar for PFS. More extreme discrepancies were found for the subjective outcome overall objective response (OR (95% CI): 1.67(1.04 to 2.68), p = 0.03 with 100% SDV; 2.45(1.49 to 4.04), p = 0.0003 without any SDV) which was mostly due to differing CT scans. Interpretation Quality assurance methods used in clinical trials should be informed by empirical evidence. In this empirical comparison, SDV was expensive and identified random errors that made little impact on results and clinical conclusions of the trial. Central monitoring using an external data source was a more efficient approach for the primary outcome of OS. For the subjective outcome objective response, an independent blinded review committee and tracking system to monitor missing scan data could be more efficient than SDV

    The role of healthcare professionals in encouraging parents to see and hold their stillborn baby: a meta-synthesis of qualitative studies.

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    Background: Globally, during 2013 there were three million recorded stillbirths. Where clinical guidelines exist some recommend that professionals do not encourage parental contact. The guidance is based on quantitative evidence that seeing and holding the baby is not beneficial for everyone, but has been challenged by bereaved parents' organisations. We aim to inform future guideline development through a synthesis of qualitative studies reporting data relevant to the research question; how does the approach of healthcare professionals to seeing and holding the baby following stillbirth impact parents views and experiences? Methods/Findings: Using a predetermined search strategy of PubMed and PsychINFO we identified robust qualitative studies reporting bereaved parental views and/or experiences relating to seeing and holding their stillborn baby (final search 24 February, 2014). Eligible studies were English language, reporting parental views, with gestational loss >20weeks. Quality was independently assessed by three authors using a validated tool. We used meta-ethnographic techniques to identify key themes and a line of argument synthesis. We included 12 papers, representing the views of 333 parents (156 mothers, 150 fathers, and 27 couples) from six countries. The final themes were: "[Still]birth: Nature of care is paramount", "Real babies: Perfect beauties, monsters and spectres", and "Opportunity of a lifetime lost." Our line-of-argument synthesis highlights the contrast between all parents need to know their baby, with the time around birth being the only time memories can be made, and the variable ability that parents have to articulate their preferences at that time. Thus, we hypothesised that how health professionals approach contact between parents and their stillborn baby demands a degree of active management. An important limitation of this paper is all included studies originated from high income, westernised countries raising questions about the findings transferability to other cultural contexts. We do not offer new evidence to answer the question "Should parents see and hold their stillborn baby?", instead our findings advance understanding of how professionals can support parents to make appropriate decisions in a novel, highly charged and dynamic situation. Conclusions: Guidelines could be more specific in their recommendations regarding parental contact. The role of healthcare professionals in encouraging parents to see and hold their stillborn baby is paramount. Parental choice not to see their baby, apprehension, or uncertainty should be continuously revisited in the hours after birth as the opportunity for contact is fleeting and final

    Biomechanical effects of polyaxial pedicle screw fixation on the lumbosacral segments with an anterior interbody cage support

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    BACKGROUND: Lumbosacral fusion is a relatively common procedure that is used in the management of an unstable spine. The anterior interbody cage has been involved to enhance the stability of a pedicle screw construct used at the lumbosacral junction. Biomechanical differences between polyaxial and monoaxial pedicle screws linked with various rod contours were investigated to analyze the respective effects on overall construct stiffness, cage strain, rod strain, and contact ratios at the vertebra-cage junction. METHODS: A synthetic model composed of two ultrahigh molecular weight polyethylene blocks was used with four titanium pedicle screws (two in each block) and two rods fixation to build the spinal construct along with an anterior interbody cage support. For each pair of the construct fixed with polyaxial or monoaxial screws, the linked rods were set at four configurations to simulate 0°, 7°, 14°, and 21° lordosis on the sagittal plane, and a compressive load of 300 N was applied. Strain gauges were attached to the posterior surface of the cage and to the central area of the left connecting rod. Also, the contact area between the block and the cage was measured using prescale Fuji super low pressure film for compression, flexion, lateral bending and torsion tests. RESULTS: Our main findings in the experiments with an anterior interbody cage support are as follows: 1) large segmental lordosis can decrease the stiffness of monoaxial pedicle screws constructs; 2) polyaxial screws rather than monoaxial screws combined with the cage fixation provide higher compression and flexion stiffness in 21° segmental lordosis; 3) polyaxial screws enhance the contact surface of the cage in 21° segmental lordosis. CONCLUSION: Polyaxial screws system used in conjunction with anterior cage support yields higher contact ratio, compression and flexion stiffness of spinal constructs than monoaxial screws system does in the same model when the spinal segment is set at large lordotic angles. Polyaxial pedicle screw fixation performs nearly equal percentages of vertebra-cage contact among all constructs with different sagittal alignments, therefore enhances the stabilization effect of interbody cages in the lumbosacral area

    Antiepileptic drugs’ tolerability and safety – a systematic review and meta-analysis of adverse effects in dogs

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    <p>Various anti-epileptic drugs (AEDs) are used for the management of idiopathic epilepsy (IE) in dogs. Their safety profile is an important consideration for regulatory bodies, owners and prescribing clinicians. However, information on their adverse effects still remains limited with most of it derived from non-blinded non-randomized uncontrolled trials and case reports.</p><p><span>This poster won third place, which was presented at the Veterinary Evidence Today conference, Edinburgh November 1-3, 2016. </span></p><br /> <img src="https://www.veterinaryevidence.org/rcvskmod/icons/oa-icon.jpg" alt="Open Access" /

    Higher incidence of persistent chronic infection of Chlamydia pneumoniae among coronary artery disease patients in India is a cause of concern

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    <p>Abstract</p> <p>Background</p> <p>There is growing evidence that <it>Chlamydia pneumoniae </it>may be involved in the pathogenesis of atherosclerosis, as several studies have demonstrated the presence of the organism in atherosclerotic lesions. <it>C. pneumoniae </it>infections, which are especially persistent infections, have been difficult to diagnose either by serological methods or isolation of the organism from the tissue. Nucleic Acid Amplification tests (NAATs) has emerged as an important method for detecting <it>C. pneumoniae</it>. Inspite of high prevalence of <it>C. pneumoniae </it>specific antibodies in coronary heart disease patients, direct detection of <it>C. pneumoniae </it>in circulating blood of coronary artery disease (CAD) patients by sensitive nucleic acid amplification tests nested PCR (nPCR), multiplex PCR (mPCR) has not been carried out is required. Further correlation of the presence of <it>C. pneumoniae </it>in blood of CAD patients with <it>C. pneumoniae </it>specific IgA and IgG antibodies, which may indicative of the status of infection with the progression of atherosclerosis. This will help in order to prepare strategies for the antibiotic intervention to avoid the progression towards CAD.</p> <p>Methods</p> <p>Venous blood was obtained from 91 CAD patients and 46 healthy controls. Nucleic acid amplification tests <it>viz</it>. nested -, semi-nested – and multiplex PCR were used for detection of <it>C. pneumoniae</it>. ELISA carried out prevalence of <it>C. pneumoniae </it>specific IgG and IgA antibodies.</p> <p>Results</p> <p>29.67% (27/91) patients were positive for <it>C. pneumoniae </it>using nested PCR. The sensitivity and specificity of semi-nested and multiplex PCR were 37.03%, 96.96% and 22.22%, 100% with respect to nested PCR. Positive nPCR patients were compared with presence of <it>C. pneumoniae </it>specific IgA, IgA+IgG and IgG antibodies. Among 27 (29.67%) nPCR <it>C. pneumoniae </it>positive CAD patients, 11(12%) were IgA positive, 13(14.2%) were IgA+IgG positive and only1 (1.1%) was IgG positive. A significant presence of <it>C. pneumoniae </it>was detected in heavy smokers, non-alcoholics and with family histories of diabetes and blood pressure group of CAD patients by nPCR.</p> <p>Conclusion</p> <p>The results indicate synergistic association of <it>C. pneumoniae </it>infection and development of CAD with other risk factors. We also detected increased positivity for <it>C. pneumoniae </it>IgA than IgG in nPCR positive CAD patients. Positive nPCR findings in conjunction with persisting high <it>C. pneumoniae </it>specific antibody strongly suggest an ongoing infection.</p

    Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

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    Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
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