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.

Opiate substitution treatment and HIV transmission in people who inject drugs: systematic review and meta-analysis.

Abstract: Objective To quantify the effect of opiate substitution treatment in relation to HIV transmission among people who inject drugs. Design Systematic review and meta-analysis of prospective published and unpublished observational studies. Data sources Search of Medline, Embase, PsychINFO, and the Cochrane Library from the earliest year to 2011 without language restriction. Review methods We selected studies that directly assessed the impact of opiate substitution treatment in relation to incidence of HIV and studies that assessed incidence of HIV in people who inject drugs and that might have collected data regarding exposure to opiate substitution treatment but not have reported it. Authors of these studies were contacted. Data were extracted by two reviewers and pooled in a meta-analysis with a random effects model. Results Twelve published studies that examined the impact of opiate substitution treatment on HIV transmission met criteria for inclusion, and unpublished data were obtained from three additional studies. All included studies examined methadone maintenance treatment. Data from nine of these studies could be pooled, including 819 incident HIV infections over 23 608 person years of follow-up. Opiate substitution treatment was associated with a 54% reduction in risk of HIV infection among people who inject drugs (rate ratio 0.46, 95% confidence interval 0.32 to 0.67; P 2 =60%, χ 2 =20.12, P=0.010), which could not be explained by geographical region, site of recruitment, or the provision of incentives. There was weak evidence for greater benefit associated with longer duration of exposure to opiate substitution treatment. Conclusion Opiate substitution treatment provided as maintenance therapy is associated with a reduction in the risk of HIV infection among people who inject drugs. These findings, however, could reflect comparatively high levels of motivation to change behaviour and reduce injecting risk behaviour among people who inject drugs who are receiving opiate substitution treatment.

The quality of clinical practice guidelines over the last two decades: a systematic review of guideline appraisal studies.

Abstract: BACKGROUND: Despite the increasing number of manuals on how to develop clinical practice guidelines (CPGs) there remain concerns about their quality. The aim of this study was to review the quality of CPGs across a wide range of healthcare topics published since 1980. METHODS: The authors conducted a literature search in MEDLINE to identify publications assessing the quality of CPGs with the Appraisal of Guidelines, Research and Evaluation (AGREE) instrument. For the included guidelines in each study, the authors gathered data about the year of publication, institution, country, healthcare topic, AGREE score per domain and overall assessment. RESULTS: In total, 42 reviews were selected, including a total of 626 guidelines, published between 1980 and 2007, with a median of 25 CPGs. The mean scores were acceptable for the domain 'Scope and purpose' (64%; 95% CI 61.9 to 66.4) and 'Clarity and presentation' (60%; 95% CI 57.9 to 61.9), moderate for domain 'Rigour of development' (43%; 95% CI 41.0 to 45.2), and low for the other domains ('Stakeholder involvement' 35%; 95% CI 33.9 to 37.5, 'Editorial independence' 30%; 95% CI 27.9 to 32.3, and 'Applicability' 22%; 95% CI 20.4 to 23.9). From those guidelines that included an overall assessment, 62% (168/270) were recommended or recommended with provisos. There was a significant improvement over time for all domains, except for 'Editorial independence.' CONCLUSIONS: This review shows that despite some increase in quality of CPGs over time, the quality scores as measured with the AGREE Instrument have remained moderate to low over the last two decades. This finding urges guideline developers to continue improving the quality of their products. International collaboration could help increasing the efficiency of the process.

Oseltamivir for influenza in adults and children: systematic review of clinical study reports and summary of regulatory comments.

Abstract: Objective To describe the potential benefits and harms of oseltamivir by reviewing all clinical study reports (or similar document when no clinical study report exists) of randomised placebo controlled trials and regulatory comments ("regulatory information"). Design Systematic review of regulatory information. Data sources Clinical study reports, trial registries, electronic databases, regulatory archives, and correspondence with manufacturers. Eligibility criteria for selecting studies Randomised placebo controlled trials on adults and children who had confirmed or suspected exposure to natural influenza. Main outcome measures Time to first alleviation of symptoms, influenza outcomes, complications, admissions to hospital, and adverse events in the intention to treat population. Results From the European Medicines Agency and Roche, we obtained clinical study reports for 83 trials. We included 23 trials in stage 1 (reliability and completeness screen) and 20 in stage 2 (formal analysis). In treatment trials on adults, oseltamivir reduced the time to first alleviation of symptoms by 16.8 hours (95% confidence interval 8.4 to 25.1 hours, P<0.001). There was no effect in children with asthma, but there was an effect in otherwise healthy children (mean difference 29 hours, 95% confidence interval 12 to 47 hours, P=0.001). In treatment trials there was no difference in admissions to hospital in adults (risk difference 0.15%, 95% confidence interval -0.91% to 0.78%, P=0.84) and sparse data in children and for prophylaxis. In adult treatment trials, oseltamivir reduced investigator mediated unverified pneumonia (risk difference 1.00%, 0.22% to 1.49%; number needed to treat to benefit (NNTB) 100, 95% confidence interval 67 to 451). The effect was not statistically significant in the five trials that used a more detailed diagnostic form for "pneumonia," and no clinical study reports reported laboratory or diagnostic confirmation of "pneumonia." The effect on unverified pneumonia in children and for prophylaxis was not significant. There was no significant reduction in risk of unverified bronchitis, otitis media, sinusitis, or any complication classified as serious or that led to study withdrawal. 14 of 20 trials prompted participants to self report all secondary illnesses to an investigator. Oseltamivir in the treatment of adults increased the risk of nausea (risk difference 3.66%, 0.90% to 7.39%; number needed to treat to harm (NNTH) 28, 95% confidence interval 14 to 112) and vomiting (4.56%, 2.39% to 7.58%; 22, 14 to 42). In treatment of children, oseltamivir induced vomiting (5.34%, 1.75% to 10.29%; 19, 10 to 57). In prophylaxis trials, oseltamivir reduced symptomatic influenza in participants by 55% (3.05%, 1.83% to 3.88%; NNTB 33, 26 to 55) and households (13.6%, 9.52% to 15.47%; NNTB 7, 6 to 11) based on one study, but there was no significant effect on.

Living systematic reviews: an emerging opportunity to narrow the evidence-practice gap

Abstract: The current difficulties in keeping systematic reviews up to date leads to considerable inaccuracy, hampering the translation of knowledge into action. Incremental advances in conventional review updating are unlikely to lead to substantial improvements in review currency. A new approach is needed. We propose living systematic review as a contribution to evidence synthesis that combines currency with rigour to enhance the accuracy and utility of health evidence. Living systematic reviews are high quality, up-to-date online summaries of health research, updated as new research becomes available, and enabled by improved production efficiency and adherence to the norms of scholarly communication. Together with innovations in primary research reporting and the creation and use of evidence in health systems, living systematic review contributes to an emerging evidence ecosystem.

Antibiotic prophylaxis to reduce respiratory tract infections and mortality in adults receiving intensive care

Abstract: Background Pneumonia is an important cause of mortality in intensive care units (ICUs). The incidence of pneumonia in ICU patients ranges between 7% and 40%, and the crude mortality from ventilator-associated pneumonia may exceed 50%. Although not all deaths in patients with this form of pneumonia are directly attributable to pneumonia, it has been shown to contribute to mortality in ICUs independently of other factors that are also strongly associated with such deaths. Objectives To assess the effects of prophylactic antibiotic regimens, such as selective decontamination of the digestive tract (SDD) for the prevention of respiratory tract infections (RTIs) and overall mortality in adults receiving intensive care. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, issue 1), which contains the Cochrane Acute Respiratory Infections (ARI) Group's Specialised Register; MEDLINE (January 1966 to March 2009); and EMBASE (January 1990 to March 2009). Selection criteria Randomised controlled trials (RCTs) of antibiotic prophylaxis for RTIs and deaths among adult ICU patients. Data collection and analysis At least two review authors independently extracted data and assessed trial quality. Main results We included 36 trials involving 6914 people. There was variation in the antibiotics used, patient characteristics and risk of RTIs and mortality in the control groups. In trials comparing a combination of topical and systemic antibiotics, there was a significant reduction in both RTIs (number of studies = 16, odds ratio (OR) 0.28, 95% confidence interval (CI) 0.20 to 0.38) and total mortality (number of studies = 17, OR 0.75, 95% CI 0.65 to 0.87) in the treated group. In trials comparing topical antimicrobials alone (or comparing topical plus systemic versus systemic alone) there was a significant reduction in RTIs (number of studies = 17, OR 0.44, 95% CI 0.31 to 0.63) but not in total mortality (number of studies = 19, OR 0.97, 95% CI 0.82 to 1.16) in the treated group. Authors' conclusions A combination of topical and systemic prophylactic antibiotics reduces RTIs and overall mortality in adult patients receiving intensive care. Treatment based on the use of topical prophylaxis alone reduces respiratory infections but not mortality. The risk of resistance occurring as a negative consequence of antibiotic use was appropriately explored only in one trial which did not show any such effect.