601 research outputs found

    Ar dreno pašalinimo laikas turi įtakos pirminio spontaninio pneumotorakso pirmojo epizodo gydymo išeitims?

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    Background / objectives. The main treatment option for the first episode of primary spontaneous pneumothorax is chest tube drainage, however, whether delayed chest tube removal might influence the recurrence is unclear.Methods. A prospective study, which included 50 patients, with an initial episode of primary spontaneous pneumothorax was performed. Patients were randomized into two groups according to the chest tube removal time: 1-day and 5-days after the air-leak has stopped. All patients were followed-up for at least six months. Both groups were compared according to the recurrence rate and possible complications.Results. There were 39 (78%) men and the median age was 27 (23–35) years. Successful management with a chest tube was achieved in 43 (86%) patients, others were operated on because of the continuous air-leak or relapse of the pneumothorax after the chest tube was removed. Significant difference was not found comparing groups by age, gender, side, tobacco smoking, alpha-1-antitrypsin level, rate of prolonged air-leak, necessity of surgery, and the mean follow-up time. There was a significant difference between groups in hospitalization time: 1-day group – 6 (4–12), 5-days group – 8 (7–10) days, p = 0.017. Five (20%) patients from 1-day group and 3 (12%) from 5-days group had a recurrence, however the difference was not significant (p = 0.702). There were no significant differences comparing groups by the recurrence time or complications.Conclusions. The recurrence rate of primary spontaneous pneumothorax was higher if the chest tube was removed earlier, however not significantly. More data and longer follow-up are necessary to confirm these findings.Įvadas / tikslas. Pirminis spontaninis pneumotoraksas yra didelė jaunų sveikų žmonių problema. Pleuros ertmės drenavimas – pagrindinis pirminio spontaninio pneumotorakso pirmojo epizodo gydymo būdas. Vis dėlto nėra žinoma, ar dreno buvimo pleuros ertmėje trukmė gali turėti įtakos recidyvų dažniui.Metodai. Atliktas perspektyvusis tyrimas, į kurį įtraukta 50 pacientų. Tiriamiesiems diagnozuotas pirminio spontaninio pneumotorakso pirmasis epizodas. Visi pacientai gydyti drenuojant pleuros ertmę. Pacientai suskirstyti į dvi grupes, atsižvelgiant į dreno pašalinimo laiką: praėjus vienai dienai ar praėjus penkioms dienoms, kai per dreną nustojo skirtis oras. Visi pacientai atokiu laikotarpiu (mažiausiai šešis mėnesius) stebėti dėl galimo recidyvo. Atlikta abiejų grupių recidyvų dažnio ir galimų komplikacijų lyginamoji analizė.Rezultatai. Vidutinis pacientų amžius – 27 (23–35) metai. 78 proc. tiriamųjų – vyrai. Drenavus pleuros ertmę, sėkmingai išgydyti 43 ligoniai (86 %). Kiti tiriamieji dėl besiskiriančio per dreną oro ar dėl rentgenogramoje matomo pakartotinio pneumotorakso, pašalinus dreną, buvo operuoti. Abiejų tiriamųjų grupių duomenys pagal amžių, lytį, pneumotorakso pasireiškimo krūtinės ląstoje pusę, rūkymą, alfa-1 antitripsino koncentraciją kraujyje, ilgesnį oro skyrimąsi per dreną ar operacijos poreikį statistiškai reikšmingai nesiskyrė. Statistiškai reikšmingai skyrėsi abiejų grupių hospitalizacijos trukmė: tiriamieji, kuriems, nustojus per dreną skirtis orui, drenas pašalintas praėjus vienai dienai, ligoninėje gulėjo vidutiniškai 6 (4–12) dienas, o tiriamieji, kuriems drenas pašalintas praėjus penkioms dienoms, – 8 (7–10) dienas (p = 0,017). Penkiems (20 %) pirmosios grupės ir trims (12 %) antrosios grupės pacientams pneumotoraksas recidyvavo (skirtumas statistiškai nereikšmingas (p = 0,702)). Statistiškai nereikšmingas skirtumas nustatytas ir tarp abiejų grupių recidyvo laiko bei komplikacijų.Išvados. Pirminio spontaninio pneumotorakso recidyvų dažnis kiek didesnis, kai drenas ištraukiamas anksčiau, tačiau lyginamųjų grupių skirtumas statistiškai nereikšmingas. Siekiant patvirtinti gautus rezultatus, reikia atlikti didesnės apimties tyrimą, būtina ilgiau stebėti tiriamuosius

    Publication bias in situ

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    BACKGROUND: Publication bias, as typically defined, refers to the decreased likelihood of studies' results being published when they are near the null, not statistically significant, or otherwise "less interesting." But choices about how to analyze the data and which results to report create a publication bias within the published results, a bias I label "publication bias in situ" (PBIS). DISCUSSION: PBIS may create much greater bias in the literature than traditionally defined publication bias (the failure to publish any result from a study). The causes of PBIS are well known, consisting of various decisions about reporting that are influenced by the data. But its impact is not generally appreciated, and very little attention is devoted to it. What attention there is consists largely of rules for statistical analysis that are impractical and do not actually reduce the bias in reported estimates. PBIS cannot be reduced by statistical tools because it is not fundamentally a problem of statistics, but rather of non-statistical choices and plain language interpretations. PBIS should be recognized as a phenomenon worthy of study – it is extremely common and probably has a huge impact on results reported in the literature – and there should be greater systematic efforts to identify and reduce it. The paper presents examples, including results of a recent HIV vaccine trial, that show how easily PBIS can have a large impact on reported results, as well as how there can be no simple answer to it. SUMMARY: PBIS is a major problem, worthy of substantially more attention than it receives. There are ways to reduce the bias, but they are very seldom employed because they are largely unrecognized

    Investigating and dealing with publication bias and other reporting biases in meta-analyses:a review

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    A P value, or the magnitude or direction of results can influence decisions about whether, when, and how research findings are disseminated. Regardless of whether an entire study or a particular study result is unavailable because investigators considered the results to be unfavourable, bias in a meta-analysis may occur when available results differ systematically from missing results. In this paper, we summarize the empirical evidence for various reporting biases that lead to study results being unavailable for inclusion in systematic reviews, with a focus on health research. These biases include publication bias and selective nonreporting bias. We describe processes that systematic reviewers can use to minimize the risk of bias due to missing results in meta-analyses of health research, such as comprehensive searches and prospective approaches to meta-analysis. We also outline methods that have been designed for assessing risk of bias due to missing results in meta-analyses of health research, including using tools to assess selective nonreporting of results, ascertaining qualitative signals that suggest not all studies were identified, and generating funnel plots to identify small-study effects, one cause of which is reporting bias. This article is protected by copyright. All rights reserved

    Chlorination Disinfection By-Products in Drinking Water and Congenital Anomalies: Review and Meta-Analyses

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    This study aims to review epidemiologic evidence of the association between exposure to chlorination disinfection by-products (DBPs) and congenital anomalies. All epidemiologic studies that evaluated a relationship between an index of DBP exposure and risk of congenital anomalies were analyzed. For all congenital anomalies combined, the meta-analysis gave a statistically significant excess risk for high versus low exposure to water chlorination or TTHM (17%; 95% CI, 3-34) based on a small number of studies. The meta-analysis also suggested a statistically significant excess risk for ventricular septal defects (58%; 95% CI, 21-107), but based on only three studies, and there was little evidence of an exposure-response relationship. It was observed no statistically significant relationships in the other meta-analyses and little evidence for publication bias, except for urinary tract defects and cleft lip and palate. Although some individual studies have suggested an association between chlorination disinfection by-products and congenital anomalies, meta-analyses of all currently available studies demonstrate little evidence of such association

    Differences in parental attitudes and tolerance of child exposure to and participation in gambling, alcohol and nicotine use

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    This study investigated parental attitudes toward child exposure to alcohol, nicotine (smoking tobacco) and gambling, via a questionnaire that examined parental tolerance with regard to hypothetical scenarios of exposure and participation, alongside perceptions of the importance of associated health promotion for each activity. It was hypothesised that parents would indicate significantly less tolerance of, and rate health promotion activity of greater importance for, nicotine and alcohol in comparison to gambling. Results from a sample of 500 UK based parents, showed significantly less tolerance for nicotine versus alcohol and gambling in all hypothetical scenarios of exposure and direct participation. Parents also reported significantly less tolerance surrounding child consumption of alcohol than gambling. Health promotion activity surrounding nicotine was rated significantly more important than that of alcohol and gambling. It is argued that greater parental concern surrounding nicotine was attributable to increased availability of knowledge surrounding associated risks of smoking behaviour within existing regulation and health promotion activity. Arguments are made for increased public awareness of the potential harms that may be associated with gambling behaviour, which may assist parents in making informed decisions regarding their children’s exposure to and participation in gambling-related activities

    Ambient Air Pollution and Risk of Congenital Anomalies: A Systematic Review and Meta-analysis

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    Objective We systematically reviewed epidemiologic studies on ambient air pollution and congenital anomalies and conducted meta-analyses for a number of air pollutant–anomaly combinations. Data sources and extraction From bibliographic searches we extracted 10 original epidemiologic studies that examined the association between congenital anomaly risk and concentrations of air pollutants. Meta-analyses were conducted if at least four studies published risk estimates for the same pollutant and anomaly group. Summary risk estimates were calculated for a) risk at high versus low exposure level in each study and b) risk per unit increase in continuous pollutant concentration. Data synthesis Each individual study reported statistically significantly increased risks for some combinations of air pollutants and congenital anomalies, among many combinations tested. In meta-analyses, nitrogen dioxide (NO2) and sulfur dioxide (SO2) exposures were related to increases in risk of coarctation of the aorta [odds ratio (OR) per 10 ppb NO2 = 1.17; 95% confidence interval (CI), 1.00–1.36; OR per 1 ppb SO2 = 1.07; 95% CI, 1.01–1.13] and tetralogy of Fallot (OR per 10 ppb NO2 = 1.20; 95% CI, 1.02–1.42; OR per 1 ppb SO2 = 1.03; 95% CI, 1.01–1.05), and PM10 (particulate matter ≤ 10 μm) exposure was related to an increased risk of atrial septal defects (OR per 10 μg/m3 = 1.14; 95% CI, 1.01–1.28). Meta-analyses found no statistically significant increase in risk of other cardiac anomalies and oral clefts. Conclusions We found some evidence for an effect of ambient air pollutants on congenital cardiac anomaly risk. Improvements in the areas of exposure assessment, outcome harmonization, assessment of other congenital anomalies, and mechanistic knowledge are needed to advance this field

    Systematic review and stratified meta-analysis of the efficacy of RhoA and Rho kinase inhibitors in animal models of ischaemic stroke

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    There is currently only one clinically approved drug, tissue plasminogen activator (tPA), for the treatment of acute ischaemic stroke. The RhoA pathway, including RhoA and its downstream effector Rho kinase (ROCK), has been identified as a possible therapeutic target. Our aim was to assess the impact of study design characteristics and study quality on reported measures of efficacy and to assess for the presence and impact of publication bias. We conducted a systematic review and meta-analysis on publications describing the efficacy of RhoA and ROCK inhibitors in animal models of focal cerebral ischaemia where outcome was assessed as a change in lesion size or neurobehavioural score, or both. We identified 25 published papers which met our inclusion criteria. RhoA and ROCK inhibitors reduced lesion size by 37.3% in models of focal cerebral ischaemia (95% CI, 28.6% to 46.0%, 41 comparisons), and reduced neurobehavioural data by 40.5% (33.4% to 47.7%, 30 comparisons). Overall study quality was low (median=4, interquartile range 3-5) and measures to reduce bias were seldom reported. Publication bias was prevalent and associated with a substantial overstatement of efficacy for lesion size. RhoA and ROCK inhibitors appear to be effective in animal models of stroke. However the low quality score, publication bias and limited number of studies are areas which need attention prior to conducting clinical trials

    Learning curves and long-term outcome of simulation-based thoracentesis training for medical students

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    <p>Abstract</p> <p>Background</p> <p>Simulation-based medical education has been widely used in medical skills training; however, the effectiveness and long-term outcome of simulation-based training in thoracentesis requires further investigation. The purpose of this study was to assess the learning curve of simulation-based thoracentesis training, study skills retention and transfer of knowledge to a clinical setting following simulation-based education intervention in thoracentesis procedures.</p> <p>Methods</p> <p>Fifty-two medical students were enrolled in this study. Each participant performed five supervised trials on the simulator. Participant's performance was assessed by performance score (PS), procedure time (PT), and participant's confidence (PC). Learning curves for each variable were generated. Long-term outcome of the training was measured by the retesting and clinical performance evaluation 6 months and 1 year, respectively, after initial training on the simulator.</p> <p>Results</p> <p>Significant improvements in PS, PT, and PC were noted among the first 3 to 4 test trials (p < 0.05). A plateau for PS, PT, and PC in the learning curves occurred in trial 4. Retesting 6 months after training yielded similar scores to trial 5 (p > 0.05). Clinical competency in thoracentesis was improved in participants who received simulation training relative to that of first year medical residents without such experience (p < 0.05).</p> <p>Conclusions</p> <p>This study demonstrates that simulation-based thoracentesis training can significantly improve an individual's performance. The saturation of learning from the simulator can be achieved after four practice sessions. Simulation-based training can assist in long-term retention of skills and can be partially transferred to clinical practice.</p

    Buffy coat specimens remain viable as a DNA source for highly multiplexed genome-wide genetic tests after long term storage

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    <p>Abstract</p> <p>Background</p> <p>Blood specimen collection at an early study visit is often included in observational studies or clinical trials for analysis of secondary outcome biomarkers. A common protocol is to store buffy coat specimens for future DNA isolation and these may remain in frozen storage for many years. It is uncertain if the DNA remains suitable for modern genome wide association (GWA) genotyping.</p> <p>Methods</p> <p>We isolated DNA from 120 Action to Control Cardiovascular Risk in Diabetes (ACCORD) clinical trial buffy coats sampling a range of storage times up to 9 years and other factors that could influence DNA yield. We performed TaqMan SNP and GWA genotyping to test whether the DNA retained integrity for high quality genetic analysis.</p> <p>Results</p> <p>We tested two QIAGEN automated protocols for DNA isolation, preferring the Compromised Blood Protocol despite similar yields. We isolated DNA from all 120 specimens (yield range 1.1-312 ug per 8.5 ml ACD tube of whole blood) with only 3/120 samples yielding < 10 ug DNA. Age of participant at blood draw was negatively associated with yield (mean change -2.1 ug/year). DNA quality was very good based on gel electrophoresis QC, TaqMan genotyping of 6 SNPs (genotyping no-call rate 1.1% in 702 genotypes), and excellent quality GWA genotyping data (maximum per sample genotype missing rate 0.64%).</p> <p>Conclusions</p> <p>When collected as a long term clinical trial or biobank specimen for DNA, buffy coats can be stored for up to 9 years in a -80degC frozen state and still produce high yields of DNA suitable for GWA analysis and other genetic testing.</p> <p>Trial Registration</p> <p>The Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial is registered with ClinicalTrials.gov, number <a href="http://www.clinicaltrials.gov/ct2/show/NCT00000620">NCT00000620</a>.</p
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