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Concept: Cochrane Collaboration


BACKGROUND: The aim of this review was to systematically review and meta-analyze the effects of yoga on symptoms of schizophrenia, quality of life, function, and hospitalization in patients with schizophrenia. METHODS: MEDLINE/Pubmed, Scopus, the Cochrane Library, PsycInfo, and IndMED were screened through August 2012. Randomized controlled trials (RCTs) comparing yoga to usual care or non-pharmacological interventions were analyzed when they assessed symptoms or quality of life in patients with schizophrenia. Cognitive function, social function, hospitalization, and safety were defined as secondary outcomes. Risk of bias was assessed using the risk of bias tool recommended by the Cochrane Back Review Group. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated. RESULTS: Five RCTs with a total of 337 patients were included; 2 RCTs had low risk of bias. Two RCTs compared yoga to usual care; 1 RCT compared yoga to exercise; and 2 3-arm RCTs compared yoga to usual care and exercise. No evidence was found for short-term effects of yoga compared to usual care on positive symptoms (SMD = -0.58; 95% CI -1.52 to 0.37; P = 0.23), or negative symptoms (SMD = -0.59; 95% CI -1.87 to 0.69; P = 0.36). Moderate evidence was found for short-term effects on quality of life compared to usual care (SMD = 2.28; 95% CI 0.42 to 4.14; P = 0.02). These effects were only present in studies with high risk of bias. No evidence was found for short-term effects on social function (SMD = 1.20; 95% CI -0.78 to 3.18; P = 0.23). Comparing yoga to exercise, no evidence was found for short-term effects on positive symptoms (SMD = -0.35; 95% CI -0.75 to 0.05; P = 0.09), negative symptoms (SMD = -0.28; 95% CI -1.42 to 0.86; P = 0.63), quality of life (SMD = 0.17; 95% CI -0.27 to 0.61; P = 0.45), or social function (SMD = 0.20; 95% CI -0.27 to 0.67; P = 0.41). Only 1 RCT reported adverse events. CONCLUSIONS: This systematic review found only moderate evidence for short-term effects of yoga on quality of life. As these effects were not clearly distinguishable from bias and safety of the intervention was unclear, no recommendation can be made regarding yoga as a routine intervention for schizophrenia patients.

Concepts: Centre for Reviews and Dissemination, MEDLINE, Meta-analysis, Cochrane Collaboration, Cochrane Library, Systematic review, Evidence-based medicine, Randomized controlled trial


Prevalence of non-communicable diseases (NCDs) is increasing globally, with the greatest projected increases in low-income and middle-income countries. We sought to quantify the proportion of Cochrane evidence relating to NCDs derived from such countries.

Concepts: Globalization, Cochrane Collaboration, Cochrane Library, Evidence-based medicine, Disease, World Bank, Randomized controlled trial, Poverty


BACKGROUND: In searches for clinical trials and systematic reviews, it is said that Google Scholar (GS) should never be used in isolation, but in addition to PubMed, Cochrane, and other trusted sources of information. We therefore performed a study to assess the coverage of GS specifically for the studies included in systematic reviews and evaluate if GS was sensitive enough to be used alone for systematic reviews. METHODS: All the original studies included in 29 systematic reviews published in the Cochrane Database Syst Rev or in the JAMA in 2009 were gathered in a gold standard database. GS was searched for all these studies one by one to assess the percentage of studies which could have been identified by searching only GS. RESULTS: All the 738 original studies included in the gold standard database were retrieved in GS (100%). CONCLUSION: The coverage of GS for the studies included in the systematic reviews is 100%. If the authors of the 29 systematic reviews had used only GS, no reference would have been missed. With some improvement in the research options, to increase its precision, GS could become the leading bibliographic database in medicine and could be used alone for systematic reviews.

Concepts: Medicine, Review, MEDLINE, Cochrane Collaboration, Evidence-based medicine, Reference management software, Search engine optimization, Bibliographic databases


Flaws in trial design may bias intervention effect estimates and increase between-trial heterogeneity. Empirical evidence suggests that these problems are greatest for subjectively assessed outcomes. For the ROBES study, we extracted risk-of-bias judgements (for sequence generation, allocation concealment, blinding and incomplete data) from a large collection of meta-analyses published in the Cochrane Library, issue 4, 2011. We categorized outcome measures as mortality, other objective or subjective, and estimated associations of bias judgements with intervention effect estimates using Bayesian hierarchical models. Among 2,443 trials in 228 meta-analyses, intervention effect estimates were on average exaggerated in trials with high or unclear risk-of-bias judgements (versus low) for sequence generation (ratio of odds ratio = 0.91 (95% credible interval 0.86, 0.98)), allocation concealment (0.92 (0.86, 0.98)) and blinding (0.87 (0.80, 0.93)). In contrast to previous work, we did not observe consistently different bias for subjective outcomes compared with mortality. However, we found an increase in between-trial heterogeneity associated with lack of blinding in meta-analyses with subjective outcomes. Inconsistency in criteria for risk-of-bias judgments applied by individual reviewers is a likely limitation of routinely collected bias assessments. Inadequate randomization and lack of blinding may lead to exaggeration of intervention effect estimates in trials.

Concepts: Scientific method, Centre for Reviews and Dissemination, MEDLINE, Systematic review, Cochrane Collaboration, Cochrane Library, Evidence-based medicine


Meta-analyses conducted via the Cochrane Collaboration adhere to strict methodological and reporting standards aiming to minimize bias, maximize transparency/reproducibility, and improve the accuracy of summarized data. Whether this results in differences in the results reported by meta-analyses on the same topic conducted outside the Cochrane Collaboration is an open question.

Concepts: Cochrane Library, Systematic review, Cochrane Collaboration, Evidence-based medicine


Cancer-related fatigue is recognised as an important symptom associated with cancer and its treatment. A number of studies have investigated the effects of physical activity in reducing cancer-related fatigue. This is an updated version of the original Cochrane review published in The Cochrane Library (2008, Issue 1). The original review identified some benefits of physical activity on fatigue in cancer both during and after adjuvant treatment. We identified a number of limitations in the evidence, providing clear justification for an updated review.

Concepts: Fatigue, Obesity, Systematic review, Centre for Reviews and Dissemination, MEDLINE, Evidence-based medicine, Cochrane Collaboration, Cochrane Library


OBJECTIVES: The objective was to evaluate the diagnostic accuracy of cystoscopy assisted by narrow-band imaging compared with white-light imaging for non-muscle-invasive bladder cancer. METHODS: An electronic database search of PubMed, Embase, the Cochrane Library, Ovid and Web of Science was carried out for all articles comparing narrow-band imaging with white-light imaging cystoscopy in the detection of non-muscle-invasive bladder cancer. The review process followed the guidelines of the Cochrane Collaboration. RESULTS: Seven studies with prospectively collected data including a total of 1040 patients were identified, and 611 patients with 1476 tumors were detected by biopsy. In the patient- and tumor-level analysis, an additional 17% of patients (95% confidence interval, 10-25%) and an additional 24% of tumors (95% confidence interval, 17-31%) were detected by narrow-band imaging, respectively. In the patient- and tumor-level analysis, significantly higher detection rates using narrow-band imaging (rate difference 11%; 95% confidence interval 5-17%; P < 0.001; and rate difference 19%; 95% confidence interval 12-26%; P < 0.001, respectively) rather than white-light imaging were found. On the tumor level, an additional 28% of carcinoma in situ was detected (95% confidence interval 14-45%) by narrow-band imaging, and a significantly higher detection rate (rate difference 11%; 95% confidence interval 1-21%; P = 0.03) was found. The false-positive detection rate of tumor level did not differ significantly between the two techniques. CONCLUSIONS: Cystoscopy assisted by narrow-band imaging detects more patients and tumors of non-muscle-invasive bladder cancer than white-light imaging, and it might be an additional or alternative diagnostic technique for non-muscle-invasive bladder cancer.

Concepts: MEDLINE, Neoplasm, Cochrane Collaboration, Carcinoma in situ, Cochrane Library, Systematic review, Cancer, Evidence-based medicine


Breakfast consumption is associated with positive outcomes for diet quality, micronutrient intake, weight status and lifestyle factors. Breakfast has been suggested to positively affect learning in children in terms of behavior, cognitive, and school performance. However, these assertions are largely based on evidence which demonstrates acute effects of breakfast on cognitive performance. Less research which examines the effects of breakfast on the ecologically valid outcomes of academic performance or in-class behavior is available. The literature was searched for articles published between 1950-2013 indexed in Ovid MEDLINE, Pubmed, Web of Science, the Cochrane Library, EMBASE databases, and PsychINFO. Thirty-six articles examining the effects of breakfast on in-class behavior and academic performance in children and adolescents were included. The effects of breakfast in different populations were considered, including undernourished or well-nourished children and adolescents from differing socio-economic status (SES) backgrounds. The habitual and acute effects of breakfast and the effects of school breakfast programs (SBPs) were considered. The evidence indicated a mainly positive effect of breakfast on on-task behavior in the classroom. There was suggestive evidence that habitual breakfast (frequency and quality) and SBPs have a positive effect on children’s academic performance with clearest effects on mathematic and arithmetic grades in undernourished children. Increased frequency of habitual breakfast was consistently positively associated with academic performance. Some evidence suggested that quality of habitual breakfast, in terms of providing a greater variety of food groups and adequate energy, was positively related to school performance. However, these associations can be attributed, in part, to confounders such as SES and to methodological weaknesses such as the subjective nature of the observations of behavior in class.

Concepts: PubMed, Effect, Evidence-based medicine, Affect, Bibliographic databases, Cochrane Collaboration, Cochrane Library, MEDLINE


Background  Adult pityriasis rubra pilaris (PRP) type 1 is a rare chronic papulosquamous disorder with clinical and histological parallels with psoriasis. Treatment is challenging and recent case reports suggest a potential role for tumour necrosis factor (TNF) antagonists. Objectives  Our objective was to systematically review the literature for evidence of efficacy of TNF antagonists in the treatment of adult PRP. Methods  We performed a systematic search of the Cochrane library, EMBASE, Pubmed and MEDLINE databases. We defined diagnosis of PRP, classified clinical response and whether this was clearly attributed to TNF-antagonists. We also reviewed disease, treatment duration and follow up. Results  Sixteen articles were selected for detailed review. From these, 12 articles (13 cases) met our predefined criteria and were included in the systematic review. The authors identified two more cases from their personal archive. A total of 15 evaluable cases were included for analysis. Twelve showed complete response (CR) (80%) to TNF-antagonists with a mean time to maximal response of 5 months. In 10 of the CR cases (83%) this was clearly attributable to TNF antagonist therapy. Conclusion  These data indicate that TNF-antagonists may be of value in treating adult type 1 PRP refractory to other systemic agents but selective reporting bias, together with the lack of standard diagnostic criteria and established spontaneous resolution in PRP, prevent any firm recommendations on their place in management.

Concepts: Cochrane Collaboration, Agonist, Diagnosis, Pityriasis rubra pilaris, Evidence-based medicine, Cochrane Library, MEDLINE, Tumor necrosis factor-alpha


Barriers obstructing evidence-based nursing have been explored in many countries. Lack of resources and evidence has been noted as one of these barriers. We aimed to identify nursing care-related systematic reviews published in the Cochrane Database of Systematic Reviews from 1996 until 2009. Using a broad search strategy we identified titles of Cochrane systematic reviews and protocols that focused on nursing care. The abstract of each title was examined and predetermined data were collected and analysed. 1249 titles out of a possible 6244 records were identified as being relevant to nursing care. Most of them focused on newborn and adult populations and related to comparing one intervention with another, and management strategies. The most common nursing specialties represented were internal medicine (34%) and mother and child care (25%). Twenty one percent of reviews published in the Cochrane Database of Systematic Reviews are of direct interest to those involved in nursing care however their relevance was not always obvious.

Concepts: Title, Randomized controlled trial, Nursing specialties, Cochrane Library, Cochrane Collaboration, Nursing, Systematic review, Evidence-based medicine