Flaws in the design, conduct, analysis, and reporting of randomised trials can cause the effect of an intervention to be underestimated or overestimated. The Cochrane Collaboration’s tool for assessing risk of bias aims to make the process clearer and more accurate

https://www.bmj.com/content/bmj/343/bmj.d5928.full.pdf

The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials

Acute decompensated heart failure (ADHF) is the most common reason for hospitalization in Western nations. The prognosis of patients admitted to hospital with ADHF is poor, with up to 64% being readmitted within the first 90 days after discharge and with a 1-year mortality approximating 20%. Epidemiological studies suggest that the majority of patients hospitalized with ADHF receive treatment that is inadequate and which is not based on scientific evidence. Furthermore, emerging data suggest that the "conventional" therapeutic interventions for ADHF including morphine, high-dose diuretics, and inotropic agents may be harmful. The goal of this review is to provide evidence-based recommendations for the diagnosis and management of ADHF.

Narrative review: the management of acute decompensated heart failure.

Research over the past two decades broadly supports the claim that mindfulness meditation - practiced widely for the reduction of stress and promotion of health - exerts beneficial effects on physical and mental health, and cognitive performance. Recent neuroimaging studies have begun to uncover the brain areas and networks that mediate these positive effects. However, the underlying neural mechanisms remain unclear, and it is apparent that more methodologically rigorous studies are required if we are to gain a full understanding of the neuronal and molecular bases of the changes in the brain that accompany mindfulness meditation.

The neuroscience of mindfulness meditation

Importance Many people meditate to reduce psychological stress and stress-related health problems. To counsel people appropriately, clinicians need to know what the evidence says about the health benefits of meditation. Objective To determine the efficacy of meditation programs in improving stress-related outcomes (anxiety, depression, stress/distress, positive mood, mental health–related quality of life, attention, substance use, eating habits, sleep, pain, and weight) in diverse adult clinical populations. Evidence Review We identified randomized clinical trials with active controls for placebo effects through November 2012 from MEDLINE, PsycINFO, EMBASE, PsycArticles, Scopus, CINAHL, AMED, the Cochrane Library, and hand searches. Two independent reviewers screened citations and extracted data. We graded the strength of evidence using 4 domains (risk of bias, precision, directness, and consistency) and determined the magnitude and direction of effect by calculating the relative difference between groups in change from baseline. When possible, we conducted meta-analyses using standardized mean differences to obtain aggregate estimates of effect size with 95% confidence intervals. Findings After reviewing 18 753 citations, we included 47 trials with 3515 participants. Mindfulness meditation programs had moderate evidence of improved anxiety (effect size, 0.38 [95% CI, 0.12-0.64] at 8 weeks and 0.22 [0.02-0.43] at 3-6 months), depression (0.30 [0.00-0.59] at 8 weeks and 0.23 [0.05-0.42] at 3-6 months), and pain (0.33 [0.03- 0.62]) and low evidence of improved stress/distress and mental health–related quality of life. We found low evidence of no effect or insufficient evidence of any effect of meditation programs on positive mood, attention, substance use, eating habits, sleep, and weight. We found no evidence that meditation programs were better than any active treatment (ie, drugs, exercise, and other behavioral therapies). Conclusions and Relevance Clinicians should be aware that meditation programs can result in small to moderate reductions of multiple negative dimensions of psychological stress. Thus, clinicians should be prepared to talk with their patients about the role that a meditation program could have in addressing psychological stress. Stronger study designs are needed to determine the effects of meditation programs in improving the positive dimensions of mental health and stress-related behavior.

https://jamanetwork.com/journals/jamainternalmedicine/articlepdf/1809754/ioi130131.pdf

Meditation Programs for Psychological Stress and Well-being: A Systematic Review and Meta-analysis

Insomnia is the most prevalent sleep disorder in the general population, and is commonly encountered in medical practices. Insomnia is defined as the subjective perception of difficulty with sleep initiation, duration, consolidation, or quality that occurs despite adequate opportunity for sleep, and that results in some form of daytime impairment.1 Insomnia may present with a variety of specific complaints and etiologies, making the evaluation and management of chronic insomnia demanding on a clinician's time. The purpose of this clinical guideline is to provide clinicians with a practical framework for the assessment and disease management of chronic adult insomnia, using existing evidence-based insomnia practice parameters where available, and consensus-based recommendations to bridge areas where such parameters do not exist. Unless otherwise stated, "insomnia" refers to chronic insomnia, which is present for at least a month, as opposed to acute or transient insomnia, which may last days to weeks.

/pdf/clinical-guideline-for-the-evaluation-and-management-of-4slg5b628w.pdf

Clinical Guideline for the Evaluation and Management of Chronic Insomnia in Adults

ContextLeft ventricular (LV) systolic dysfunction causes substantial morbidity and mortality, even with optimal pharmacotherapy. Atrial-synchronized biventricular pacemakers (cardiac resynchronization therapy [CRT]) received US Food and Drug Administration (FDA) approval for use in selected patients with LV systolic dysfunction in 2001.ObjectiveTo summarize the current evidence base for the efficacy, effectiveness, and safety of CRT in patients with LV systolic dysfunction.Evidence AcquisitionA search of multiple electronic databases until November 2006 was supplemented by hand searches of reference lists of included studies and review articles, proceedings booklets from meetings, FDA reports, and contact with primary study authors and device manufacturers. A total of 14 randomized trials (4420 patients) were included for the CRT efficacy review, 106 studies (9209 patients) for the CRT effectiveness review, and 89 studies (9677 patients) reported safety outcomes with implantation of a CRT device.Evidence SynthesisAll patients in the CRT studies had LV systolic dysfunction (mean LV ejection fraction [LVEF] range, 21%-30%), prolonged QRS duration (mean range, 155-209 milliseconds), and 91% had New York Heart Association (NYHA) class 3 or 4 heart failure symptoms despite optimal pharmacotherapy. CRT improved LVEF (weighted mean difference, 3.0%; 95% confidence interval [CI], 0.9%-5.1%), quality of life (weighted mean reduction in Minnesota Living With Heart Failure Questionnaire, 8.0 points; 95% CI, 5.6-10.4 points), and functional status (improvements of ≥1 NYHA class were observed in 59% of CRT recipients in the randomized trials). CRT decreased hospitalizations by 37% (95% CI, 7%-57%), and all-cause mortality decreased by 22% (95% CI, 9%-33%). Implant success rate was 93.0% (95% CI, 92.2%-93.7%) and 0.3% of patients died during implantation (95% CI, 0.1%-0.6%). During a median 11-month follow-up, 6.6% (95% CI, 5.6%-7.4%) of CRT devices exhibited lead problems and 5% (95% CI, 4%-7%) malfunctioned.ConclusionsCRT reduces morbidity and mortality in patients with LV systolic dysfunction, prolonged QRS duration, and NYHA class 3 or 4 symptoms when combined with optimal pharmacotherapy. The incremental benefits of combined CRT plus implantable cardioverter-defibrillator devices vs CRT-alone devices in patients with LV systolic dysfunction remain uncertain.

https://jamanetwork.com/journals/jama/articlepdf/1108372/jcr70006_2502_2514.pdf

Cardiac resynchronization therapy for patients with left ventricular systolic dysfunction: a systematic review.

Objectives To review and synthesize the state of research on a variety of meditation practices, including: the specific meditation practices examined; the research designs employed and the conditions and outcomes examined; the efficacy and effectiveness of different meditation practices for the three most studied conditions; the role of effect modifiers on outcomes; and the effects of meditation on physiological and neuropsychological outcomes. Data sources Comprehensive searches were conducted in 17 electronic databases of medical and psychological literature up to September 2005. Other sources of potentially relevant studies included hand searches, reference tracking, contact with experts, and gray literature searches. Review methods A Delphi method was used to develop a set of parameters to describe meditation practices. Included studies were comparative, on any meditation practice, had more than 10 adult participants, provided quantitative data on health-related outcomes, and published in English. Two independent reviewers assessed study relevance, extracted the data and assessed the methodological quality of the studies. Results Five broad categories of meditation practices were identified (Mantra meditation, Mindfulness meditation, Yoga, Tai Chi, and Qi Gong). Characterization of the universal or supplemental components of meditation practices was precluded by the theoretical and terminological heterogeneity among practices. Evidence on the state of research in meditation practices was provided in 813 predominantly poor-quality studies. The three most studied conditions were hypertension, other cardiovascular diseases, and substance abuse. Sixty-five intervention studies examined the therapeutic effect of meditation practices for these conditions. Meta-analyses based on low-quality studies and small numbers of hypertensive participants showed that TM(R), Qi Gong and Zen Buddhist meditation significantly reduced blood pressure. Yoga helped reduce stress. Yoga was no better than Mindfulness-based Stress Reduction at reducing anxiety in patients with cardiovascular diseases. No results from substance abuse studies could be combined. The role of effect modifiers in meditation practices has been neglected in the scientific literature. The physiological and neuropsychological effects of meditation practices have been evaluated in 312 poor-quality studies. Meta-analyses of results from 55 studies indicated that some meditation practices produced significant changes in healthy participants. Conclusions Many uncertainties surround the practice of meditation. Scientific research on meditation practices does not appear to have a common theoretical perspective and is characterized by poor methodological quality. Firm conclusions on the effects of meditation practices in healthcare cannot be drawn based on the available evidence. Future research on meditation practices must be more rigorous in the design and execution of studies and in the analysis and reporting of results.

Meditation practices for health: state of the research.

Objective To conduct a systematic review of the efficacy and safety of exogenous melatonin in managing secondary sleep disorders and sleep disorders accompanying sleep restriction, such as jet lag and shiftwork disorder.

Data sources 13 electronic databases and reference lists of relevant reviews and included studies; Associated Professional Sleep Society abstracts (1999 to 2003).

Study selection The efficacy review included randomised controlled trials; the safety review included randomised and non-randomised controlled trials.

Quality assessment Randomised controlled trials were assessed by using the Jadad Scale and criteria by Schulz et al, and non-randomised controlled trials by the Downs and Black checklist.

Data extraction and synthesis One reviewer extracted data and another reviewer verified the data extracted. The inverse variance method was used to weight studies and the random effects model was used to analyse data.

Main results Six randomised controlled trials with 97 participants showed no evidence that melatonin had an effect on sleep onset latency in people with secondary sleep disorders (weighted mean difference −13.2 (95% confidence interval −27.3 to 0.9) min). Nine randomised controlled trials with 427 participants showed no evidence that melatonin had an effect on sleep onset latency in people who had sleep disorders accompanying sleep restriction (−1.0 (−2.3 to 0.3) min). 17 randomised controlled trials with 651 participants showed no evidence of adverse effects of melatonin with short term use (three months or less).

Conclusions There is no evidence that melatonin is effective in treating secondary sleep disorders or sleep disorders accompanying sleep restriction, such as jet lag and shiftwork disorder. There is evidence that melatonin is safe with short term use.

https://www.bmj.com/content/bmj/332/7538/385.full.pdf

Efficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: meta-analysis

BACKGROUND: Exogenous melatonin has been increasingly used in the management of sleep disorders.

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The efficacy and safety of exogenous melatonin for primary sleep disorders. A meta-analysis.

Objectives To evaluate the risk of bias tool, introduced by the Cochrane Collaboration for assessing the internal validity of randomised trials, for inter-rater agreement, concurrent validity compared with the Jadad scale and Schulz approach to allocation concealment, and the relation between risk of bias and effect estimates. Design Cross sectional study. Study sample 163 trials in children. Main outcome measures Inter-rater agreement between reviewers assessing trials using the risk of bias tool (weighted κ), time to apply the risk of bias tool compared with other approaches to quality assessment (paired t test), degree of correlation for overall risk compared with overall quality scores (Kendall’s τ statistic), and magnitude of effect estimates for studies classified as being at high, unclear, or low risk of bias (metaregression). Results Inter-rater agreement on individual domains of the risk of bias tool ranged from slight (κ=0.13) to substantial (κ=0.74). The mean time to complete the risk of bias tool was significantly longer than for the Jadad scale and Schulz approach, individually or combined (8.8 minutes (SD 2.2) per study v 2.0 (SD 0.8), P Conclusions Inter-rater agreement varied across domains of the risk of bias tool. Generally, agreement was poorer for those items that required more judgment. There was low correlation between assessments of overall risk of bias and two common approaches to quality assessment: the Jadad scale and Schulz approach to allocation concealment. Overall risk of bias as assessed by the risk of bias tool differentiated effect estimates, with more conservative estimates for studies at low risk.

https://www.bmj.com/content/bmj/339/bmj.b4012.full.pdf

Nicola Hooton

Papers

Cardiac resynchronization therapy for patients with left ventricular systolic dysfunction: a systematic review.

Meditation practices for health: state of the research.

Efficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: meta-analysis

The efficacy and safety of exogenous melatonin for primary sleep disorders. A meta-analysis.

Risk of bias versus quality assessment of randomised controlled trials: cross sectional study.