(1) To generate a list of items that experts consider most important when reporting a Bayesian analysis of a clinical study, (2) to report on the extent to which we found these items in the literature, and (3) to identify factors related to the number of items in a report.
Based on opinions from 23 international experts, we determined the items considered most important when publishing a Bayesian analysis. We then performed a literature search to identify articles in which a Bayesian analysis was performed and determined the extent to which we found these items in each report. Finally, we examined the relationship between the number of items in a report and journal- and article-specific attributes.
Our final set of seven items described the prior distribution (specification, justification, and sensitivity analysis), analysis (statistical model and analytic technique), and presentation of results (central tendency and variance). There was >99% probability that more items were reported in studies with a noncontrolled study design and in journals with a methodological focus, lower impact factor, and absence of a word count limit.
We developed a set of seven items that experts believe to be most important when reporting a Bayesian analysis.
"Heterogeneity between included studies will be assessed using both the chi-square test and the I2 statistic
[45,46]. In addition, to make the probability statement for the efficacy of vitamin D and to incorporate the prior beliefs and external information (that is, observational data), we will synthesize the results from the RCTs using a hierarchical Bayesian random-effects model
[47-49] in conjunction with observational studies included in a recent systematic review
. Specifically, observational studies investigating relationship between vitamin D measurements as a risk factor and depression as the outcome of interest in adults will be eligible for pooled analysis as prior distributions to conduct Bayesian meta-analysis. "
[Show abstract][Hide abstract] ABSTRACT: The role of vitamin D in management of depression is unclear. Results from observational and emerging randomized controlled trials (RCTs) investigating the efficacy of vitamin D in depression lack consistency - with some suggesting a positive association while others show a negative or inconclusive association.
The primary aim of this study is to conduct a systematic review of RCTs to assess the effect of oral vitamin D supplementation versus placebo on depression symptoms measured by scales and the proportion of patients with symptomatic improvement according to the authors' original definition. Secondary aims include assessing the change in quality of life, adverse events and treatment discontinuation. We will conduct the systematic review and meta-analysis according to the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions. We will search the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (1966 to present), EMBASE (1980 to present), CINAHL (1982 to present), PsychINFO (1967 to present) and ClinicalTrials.gov. Unpublished work will be identified by searching two major conferences: the International Vitamin Conference, the Anxiety Disorders and Depression Conference, while grey literature will be acquired by contacting authors of included studies. We will use the random-effects meta-analysis to synthesize the data by pooling the results of included studies.
The results of this systematic review will be helpful in clarifying the efficacy of vitamin D supplementation and providing evidence to establish guidelines for implementation of vitamin D for depression in general practice and other relevant settings.Study registration: Unique identifier: CRD42013003849.
"ITC was conducted for the unadjusted analysis using Bayesian methods in WinBUGS software version 1.4.3 , which performs Bayesian analysis using Markov Chain Monte Carlo methods (see additional file 2 for software code). We reported the analysis according to the Reporting Of Bayes used in clinical STudies (ROBUST) criteria . The outcome estimated was the mean and the 95% credibility interval of the posterior distribution of the odds ratio of the rate of fracture versus placebo and other drugs, for each fracture. "
[Show abstract][Hide abstract] ABSTRACT: In the absence of head-to-head trials, indirect comparisons of randomized placebo-controlled trials may provide a viable option to assess relative efficacy. The purpose was to estimate the relative efficacy of reduction of fractures in post-menopausal women, and to assess robustness of the results.
A systematic literature review of multiple databases identified randomized placebo-controlled trials with nine drugs for post-menopausal women. Odds ratio and 95% credibility intervals for the rates of hip, non-vertebral, vertebral, and wrist fractures for each drug and between drugs were derived using a Bayesian approach. A drug was ranked as the most efficacious if it had the highest posterior odds ratio, or had the highest effect size.
30 studies including 59,209 patients reported fracture rates for nine drugs: alendronate (6 studies), denosumab (1 study), etidronate (8 studies), ibandronate (4 studies), raloxifene (1 study), risedronate (7 studies), strontium (2 study), teriparatide (1 study), and zoledronic acid (1 study). The drugs with the highest probability of reducing non-vertebral fractures was etidronate and teriparatide while the drugs with the highest probability of reducing vertebral, hip or wrist fractures were teriparatide, zoledronic acid and denosumab. The drugs with the largest effect size for vertebral fractures were zoledronic acid, teriparatide and denosumab, while the drugs with the highest effect size for non-vertebral, hip or wrist fractures were alendronate or risedronate. Estimates were consistent between Bayesian and classical approaches.
Teriparatide, zoledronic acid and denosumab have the highest probabilities of being most efficacious for non-vertebral and vertebral fractures, and having the greatest effect sizes. The estimates from indirect comparisons were robust to differences in methodology.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.