introduction: the purpose of this article was to evaluate the quality of sample size calculation reports in published clinical trials in journal of endodontics and international endodontic journal in years 2000-1 and 2009-10. materials and methods: articles fulfilling the inclusion criteria were collected. the criteria were: publication year, research design, types of control group, reporting s...

adenoviruses are recognized as common human pathogens that are responsible for a wide variety of infectious syndromes. bone marrow transplant patients are prone to life threatening opportunistic infections like adenoviruses. the nested polymerase chain reaction has provided an alternative, sensitive diagnostic method for detection of adenoviruses. in this study we developed pcr from hexon genes...

Click here for Korean Translation. Calculating the sample size is a vital step during the planning of a study in order to ensure the desired power for detecting clinically meaningful differences. However, estimating the sample size is not always straightforward. A number of key components should be considered to calculate a suitable sample size. In this paper, general considerations for conduct...

OBJECTIVES To examine the risks of bias, risks of random errors, reporting quality, and methodological quality of randomized clinical trials of oral health interventions and the development of these aspects over time. METHODS We included 540 randomized clinical trials from 64 selected systematic reviews. We extracted, in duplicate, details from each of the selected randomized clinical trials ...

OBJECTIVES Findings from nonrandomized studies on safety or efficacy of treatment in patient subgroups may trigger postlaunch randomized clinical trials (RCTs). In the analysis of such RCTs, results from nonrandomized studies are typically ignored. This study explores the trade-off between bias and power of Bayesian RCT analysis incorporating information from nonrandomized studies. STUDY DESI...

High-quality randomised controlled trials (RCTs) evaluating surgical therapies are fundamental to the delivery of evidence-based orthopaedics. Orthopaedic clinical trials have unique challenges; however, when these challenges are overcome, evidence from trials can be definitive in its impact on surgical practice. In this review, we highlight several issues that pose potential challenges to orth...

Randomized clinical trial (RCT) study design leads to one of the highest levels of evidence, and is a preferred study design over cohort studies, because randomization reduces bias and maximizes the chance that even unknown confounding factors will be balanced between treatment groups. Recent randomized clinical trials and observational studies in amblyopia can be taken together to formulate an...

where F1, F2 are cumulative distributions (discrete or continuous) of the observations and Tis their upper limit. The test is shown to be asymptotically normal and consistent against one-sided alternatives F1(t) < F2(t) (t ~ T) and against two-sided alternatives where either F1(t) < F2(t) or F1(t) > F2(t) (t ~ T). The asymptotic efficiency of the test relative to the efficient parametric test w...

Cost-effectiveness models are commonly utilized to determine the combined clinical and economic impact of one treatment compared to another. However, most methods for sample size determination of cost-effectiveness studies assume fully observed costs and effectiveness outcomes, which presents challenges for survival-based studies in which censoring exists. We propose a Bayesian method for the d...

BACKGROUND Although randomized clinical trials (RCTs) are considered the gold standard of evidence, their reporting is often suboptimal. Trial registries have the potential to contribute important methodologic information for critical appraisal of study results. METHODS AND FINDINGS The objective of the study was to evaluate the reporting of key methodologic study characteristics in trial reg...