Trends in the methodological quality of published randomized controlled trials on antibacterial agents

Blinding in Clinical Trials: Seeing the Big Picture

Blinding mitigates several sources of bias which, if left unchecked, can quantitively affect study outcomes. Blinding remains under-utilized, particularly in non-pharmaceutical clinical trials, but is often highly feasible through simple measures. Although blinding is generally viewed as an effective method by which to eliminate bias, blinding does also pose some inherent limitations, and it behooves clinicians and researchers to be aware of such caveats. This article will review general principles for blinding in clinical trials, including examples of useful blinding techniques for both pharmaceutical and non-pharmaceutical trials, while also highlighting the limitations and potential consequences of blinding. Appropriate reporting on blinding in trial protocols and manuscripts, as well as future directions for blinding research, will also be discussed.

Is the trend to publish reviews and clinical trials related to the journal impact factor? Analysis in dentistry field

It is generally accepted that the Journal Impact Factor is a quality criterion. The objective was to determine the evolution along the period 2010-2016 of number of different types of papers, reviews and clinical trials, published by dental journals, as well as if they are related with the quartile occupied in the Journal Impact Factor 2017 ranking. To this end, ten journals per quartile belonging to the field Dentistry, Oral Surgery and Medicine in the 2017 Journal Citation Reports were randomly selected. For each journal and year, the total number of narrative reviews, systematic reviews (with and without meta-analysis), meta-analysis, clinical trials and randomized controlled trials were obtained from Pubmed. To achieve our goal, the slope of these variables over time was estimated using the least squares method, after which one-way analysis of variance of mean values was performed. In Dentistry, the journals of the top quartiles show a trend to publish increasing amounts of systematic reviews and meta-analysis, than the ones of the third and fourth quartile. On the other hand, globally, there was virtually no increase in narrative reviews, clinical trials and randomized controlled trial. Possible causes of this behavior are also discussed in this article.

Multicentre open-label randomised controlled trial to compare colistin alone with colistin plus meropenem for the treatment of severe infections caused by carbapenem-resistant Gram-negative infections (AIDA): a study protocol

INTRODUCTION

The emergence of antibiotic-resistant bacteria has driven renewed interest in older antibacterials, including colistin. Previous studies have shown that colistin is less effective and more toxic than modern antibiotics. In vitro synergy studies and clinical observational studies suggest a benefit of combining colistin with a carbapenem. A randomised controlled study is necessary for clarification.

METHODS AND ANALYSIS

This is a multicentre, investigator-initiated, open-label, randomised controlled superiority 1:1 study comparing colistin monotherapy with colistin-meropenem combination therapy for infections caused by carbapenem-resistant Gram-negative bacteria. The study is being conducted in 6 centres in 3 countries (Italy, Greece and Israel). We include patients with hospital-associated and ventilator-associated pneumonia, bloodstream infections and urosepsis. The primary outcome is treatment success at day 14, defined as survival, haemodynamic stability, stable or improved respiratory status for patients with pneumonia, microbiological cure for patients with bacteraemia and stability or improvement of the Sequential Organ Failure Assessment (SOFA) score. Secondary outcomes include 14-day and 28-day mortality as well as other clinical end points and safety outcomes. A sample size of 360 patients was calculated on the basis of an absolute improvement in clinical success of 15% with combination therapy. Outcomes will be assessed by intention to treat. Serum colistin samples are obtained from all patients to obtain population pharmacokinetic models. Microbiological sampling includes weekly surveillance samples with analysis of resistance mechanisms and synergy. An observational trial is evaluating patients who met eligibility requirements but were not randomised in order to assess generalisability of findings.

ETHICS AND DISSEMINATION

The study was approved by ethics committees at each centre and informed consent will be obtained for all patients. The trial is being performed under the auspices of an independent data and safety monitoring committee and is included in a broad dissemination strategy regarding revival of old antibiotics.

TRIAL REGISTRATION NUMBER

NCT01732250 and 2012-004819-31; Pre-results.

Assessment of the Methodologic Quality of Medical and Surgical Clinical Trials in Patients with Arthroplasty

Objective.

To assess the methodological quality of randomized controlled trials (RCT) of medical and surgical therapy in patients with arthroplasty.

Methods.

We conducted a Medline database search for all arthroplasty RCT from 1997 and 2006. The quality of the methods of all eligible RCT was assessed by a trained abstractor. We used a checklist of trial quality characteristics, and the overall trial quality was assessed by 3 scales: Jadad (range 0–5), Delphi list (range 0–9), and numeric rating scale (NRS; range 1–10), based on User’s Guides to the Medical Literature.

Results.

A total of 196 articles were included in the analysis; most included hip (n = 81) or knee (n = 80) or both hip/knee arthroplasty (n = 19); 66 (34%) assessed pharmacological treatments, 117 (60%) nonpharmacological treatments, and 13 (7%) both. Mean (SEM) overall quality scores of arthroplasty RCT were low: Jadad score 2.36 (1.4), Delphi list 5.33 (1.6), and NRS score 4.30 (2.6). Multivariable analyses revealed that nonpharmacological intervention RCT had lower odds (odds ratio 0.28–0.39; p = 0.008–0.033) and those with no funding had lower odds (OR 0.28–0.50; p = 0.014–0.119) of being in the highest quartiles of the 3 overall quality scores. In contrast, multicenter RCT had 1.8–4.7 times higher odds of being in highest tertiles of quality scores (p = 0.017–0.185).

Conclusion.

Methodological deficiencies in reporting of hip/knee arthroplasty RCT offer an opportunity for improvement. Type of intervention, number of trial centers, and presence of funding were independently associated with overall trial quality. In future, multicenter RCT (rather than single-center) and modeling protocols of single-center RCT similar in rigor to multicenter RCT may improve the quality of arthroplasty RCT.