Cochrane Collaboration

About: Cochrane Collaboration is a nonprofit organization based out in Oxford, United Kingdom. It is known for research contribution in the topics: Systematic review & Randomized controlled trial. The organization has 1995 authors who have published 3928 publications receiving 382695 citations.

Polyhalogenated aromatic hydrocarbons and metabolites: Relation to circulating thyroid hormone and retinol in nestling bald eagles (Haliaeetus leucocephalus)

Abstract: Polyhalogenated aromatic hydrocarbons are global contaminants that are often considered to be endocrine disruptors and include 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (p,p 0 -DDE), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). The present study examined these compounds and their hydroxylated metabolites or analogues and relationships with circulating thyroid hormones and retinols in plasma from nestling and adult bald eagles in British Columbia, Canada, and California, USA. We also compared our results with published data. Thyroxine (T4) decreased with P PCB and CB153 in nestling bald eagles, which was congruent with results from nine of 14 other published avian laboratory and field studies. Free thyroid hormone levels also decreased with CB-153 and hydroxylated PCBs (OH-PCBs). Retinol increased with CB118 and CB180 in nestling eagles, decreased with OH-PCBs in a subset of nestlings, and decreased in 7 of 12 PCB published studies. Thyroxine decreased with p,p 0 -DDE for nestlings and with data reported in one of five other published studies. In our samples, plasma retinol, triiodothyronine (T3), and T4 were independent of P PBDEs, whereas P OH-PBDEs were weakly but significantly correlated with increases in T3 and retinol. Adult bald eagles showed no relationship between contaminants and thyroid hormones, which is consistent with other studies of long-lived birds, perhaps because adult birds have time to adjust to contaminant levels. Measurement of circulating thyroid hormones appears to be a more useful biomarker than retinols, given the more consistent response of T4 to PCBs here and reported in the literature. We conclude that current environmental exposures to PCBs in British Columbia and in southern California are associated with significant decreases in T4, suggesting a potential negative effect on the endocrine system of nestling bald eagles. Environ. Toxicol. Chem. 2010;29:1301- 1310. # 2010 SETAC

Clinical study reports of randomised controlled trials: an exploratory review of previously confidential industry reports

Abstract: Objective To explore the structure and content of a non-random sample of clinical study reports (CSRs) to guide clinicians and systematic reviewers. Search strategy We searched public sources and lodged Freedom of Information requests for previously confidential CSRs primarily written by the industry for regulators. Selection criteria CSRs reporting sufficient information for extraction (‘adequate’). Primary outcome measures Presence and length of essential elements of trial design and reporting and compression factor (ratio of page length for CSRs compared to its published counterpart in a scientific journal). Data extraction Data were extracted on standard forms and crosschecked for accuracy. Results We assembled a population of 78 CSRs (covering 90 randomised controlled trials; 144 610 pages total) dated 1991–2011 of 14 pharmaceuticals. Report synopses had a median length of 5 pages, efficacy evaluation 13.5 pages, safety evaluation 17 pages, attached tables 337 pages, trial protocol 62 pages, statistical analysis plan 15 pages and individual efficacy and safety listings had a median length of 447 and 109.5 pages, respectively. While 16 (21%) of CSRs contained completed case report forms, these were accessible to us in only one case (765 pages representing 16 individuals). Compression factors ranged between 1 and 8805. Conclusions Clinical study reports represent a hitherto mostly hidden and untapped source of detailed and exhaustive data on each trial. They should be consulted by independent parties interested in a detailed record of a clinical trial, and should form the basic unit for evidence synthesis as their use is likely to minimise the problem of reporting bias. We cannot say whether our sample is representative and whether our conclusions are generalisable to an undefined and undefinable population of CSRs.

Efficacy and safety of treatment with biologicals (benralizumab, dupilumab and omalizumab) for severe allergic asthma: A systematic review for the EAACI Guidelines - recommendations on the use of biologicals in severe asthma

Abstract: Allergic asthma is a frequent asthma phenotype. Both IgE and type 2 cytokines are increased, with some degree of overlap with other phenotypes. Systematic reviews assessed the efficacy and safety of benralizumab, dupilumab and omalizumab (alphabetical order) vs standard of care for patients with uncontrolled severe allergic asthma. PubMed, Embase and Cochrane Library were searched to identify RCTs and health economic evaluations, published in English. Critical and important asthma-related outcomes were evaluated. The risk of bias and the certainty of the evidence were assessed using GRADE. All three biologicals reduced with high certainty the annualized asthma exacerbation rate: benralizumab incidence rate ratios (IRR) 0.63 (95% CI 0.50 - 0.81); dupilumab IRR 0.58 (95%CI 0.47 - 0.73); and omalizumab IRR 0.56 (95%CI 0.42 - 0.73). Benralizumab and dupilumab improved asthma control with high certainty and omalizumab with moderate certainty; however, none reached the minimal important difference (MID). Both benralizumab and omalizumab improved QoL with high certainty, but only omalizumab reached the MID. Omalizumab enabled ICS dose reduction with high certainty. Benralizumab and omalizumab showed an increase in drug-related adverse events (AEs) with low to moderate certainty. All three biologicals had moderate certainty for an ICER/QALY value above the willingness to pay threshold. There was high certainty that in children 6-12 years old omalizumab decreased the annualized exacerbation rate [IRR 0.57 (95%CI 0.45-0.72)], improved QoL [relative risk 1.43 (95%CI 1.12 -1.83)], reduced ICS [mean difference (MD) -0.45 (95% CI -0.58 to -0.32)] and rescue medication use [ MD -0.41 (95%CI -0.66 to -0.15)].

Closed tracheal suction systems versus open tracheal suction systems for mechanically ventilated adult patients

Abstract: Background Ventilator-associated pneumonia is a common complication in ventilated patients. Endotracheal suctioning is a procedure that may constitute a risk factor for ventilator-associated pneumonia. It can be performed with an open system or with a closed system. In view of suggested advantages being reported for the closed system, a systematic review comparing both techniques was warranted. Objectives To compare the closed tracheal suction system and the open tracheal suction system in adults receiving mechanical ventilation for more than 24 hours. Search methods We searched CENTRAL (The Cochrane Library 2006, Issue 1) MEDLINE, CINAHL, EMBASE and LILACS from their inception to July 2006. We handsearched the bibliographies of relevant identified studies, and contacted authors and manufacturers. Selection criteria The review included randomized controlled trials comparing closed and open tracheal suction systems in adult patients who were ventilated for more than 24 hours. Data collection and analysis We included the relevant trials fitting the selection criteria. We assessed methodological quality using method of randomization, concealment of allocation, blinding of outcome assessment and completeness of follow up. Effect measures used for pooled analyses were relative risk (RR) for dichotomous data and weighted mean differences (WMD) for continuous data. We assessed heterogeneity prior to meta-analysis. Main results Of the 51 potentially eligible references, the review included 16 trials (1684 patients), many with methodological weaknesses. The two tracheal suction systems showed no differences in risk of ventilator-associated pneumonia (11 trials; RR 0.88; 95% CI 0.70 to 1.12), mortality (five trials; RR 1.02; 95% CI 0.84 to 1.23) or length of stay in intensive care units (two trials; WMD 0.44; 95% CI -0.92 to 1.80). The closed tracheal suction system produced higher bacterial colonization rates (five trials; RR 1.49; 95% CI 1.09 to 2.03). Authors' conclusions Results from 16 trials showed that suctioning with either closed or open tracheal suction systems did not have an effect on the risk of ventilator-associated pneumonia or mortality. More studies of high methodological quality are required, particularly to clarify the benefits and hazards of the closed tracheal suction system for different modes of ventilation and in different types of patients.

Complementary medicine use by men with prostate cancer: a systematic review of prevalence studies

Abstract: Men with prostate cancer are reported as commonly using complementary and alternative medicine (CAM) but surveys have not recently been subjected to a rigorous systematic review incorporating quality assessment. Six electronic databases were searched using pre-defined terms. Detailed information was extracted systematically from each relevant article. Study reporting quality was assessed using a quality assessment tool, which demonstrated acceptable inter-rater reliability and produces a percentage score. In all, 42 studies are reviewed. All were published in English between 1999 and 2009; 60% were conducted in the United States. The reporting quality was mixed (median score = 66%, range 23-94%). Significant heterogeneity precluded formal meta-analysis. In all, 39 studies covering 11,736 men reported overall prevalence of CAM use; this ranged from 8 to 90% (median=30%). In all, 10 studies reported prevalence of CAM use specifically for cancer care; this ranged from 8 to 50% (median = 30%). Some evidence suggested CAM use is more common in men with higher education/incomes and more severe disease. The prevalence of CAM use among men with prostate cancer varies greatly across studies. Future studies should use standardised and validated data collection techniques to reduce bias and enhance comparability.