What errors do peer reviewers detect,and does training improve their ability to detect them?

Objective

To analyse data from a trial and report the frequencies with which major and minor errors are detected at a general medical journal, the types of errors missed and the impact of training on error detection.

Design

607 peer reviewers at the BMJ were randomized to two intervention groups receiving different types of training (face-to-face training or a self-taught package) and a control group. Each reviewer was sent the same three test papers over the study period, each of which had nine major and five minor methodological errors inserted.

Setting

BMJ peer reviewers.

Main outcome measures

The quality of review, assessed using a validated instrument, and the number and type of errors detected before and after training.

Results

The number of major errors detected varied over the three papers. The interventions had small effects. At baseline (Paper 1) reviewers found an average of 2.58 of the nine major errors, with no notable difference between the groups. The mean number of errors reported was similar for the second and third papers, 2.71 and 3.0, respectively. Biased randomization was the error detected most frequently in all three papers, with over 60% of reviewers rejecting the papers identifying this error. Reviewers who did not reject the papers found fewer errors and the proportion finding biased randomization was less than 40% for each paper.

Conclusions

Editors should not assume that reviewers will detect most major errors, particularly those concerned with the context of study. Short training packages have only a slight impact on improving error detection.     

What is to be done with vancomycin-resistant enterococcal infections?

Recently, three epidemics in Dutch hospitals were caused by vancomycin-resistant enterococci (VRE). Although the number of infections was small, spread of colonization was extensive and many infection control measures were necessary to prevent further spread. VRE are relatively avirulent bacteria. However, few, if any, antibiotics are available for treatment of infections caused by VRE and the genetic code for resistance may be transferable to other, more virulent, bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). Although colonization and infection with MRSA have become endemic in many surrounding countries, such a situation has been prevented in the Netherlands by employing an aggressive 'search and destroy' policy. Although many questions regarding the optimal approach of VRE remain unanswered, a similar policy as employed for MRSA will not be possible. In contrast to MRSA, colonization with VRE occurs in the open population, no populations with increased risk for colonization appear to be definable and colonization cannot be eradicated. Based on common sense, a differentiated approach seems indicated in which extensive infection control measures should only be implemented when spread of a single genotype has been demonstrated. A reference laboratory should be created for uniform genotyping.     

Probiotics: A new way to fight bacterial pulmonary infections?

Antibiotics, of which Fleming has identified the first representative, penicillin, in 1928, allowed dramatical improvement of the treatment of patients presenting with infectious diseases. However, once an antibiotic is used, resistance may develop more or less rapidly in some bacteria. It is thus necessary to develop therapeutic alternatives, such as the use of probiotics, defined by the World Health Organization (WHO) as “micro-organisms which, administered live and in adequate amounts, confer a benefit to the health of the host”. The scope of these micro-organisms is broad, concerning many areas including that of infectious diseases, especially respiratory infections. We describe the rational use of probiotics in respiratory tract infections and detail the results of various clinical studies describing the use of probiotics in the management of respiratory infections such as nosocomial or community acquired pneumonia, or on specific grounds such as cystic fibrosis. The results are sometimes contradictory, but the therapeutic potential of probiotics seems promising. Implementing research to understand their mechanisms of action is critical to conduct therapeutic tests based on a specific rational for the strains to be used, the dose, as well as the chosen mode and rhythm of administration.     

Reality check: should we try to detect and isolate vancomycin-resistant enterococci patients?

Antimicrobial resistance, including vancomycin resistance in enterococci (VRE), is a growing problem in healthcare facilities. This "Reality Check" session focused on the question of whether we should try to detect and isolate patients colonized or infected with VRE.     

The major epidemic infections: a gift from the Old World to the New?

With the discovery of the New World, the Europeans flocked to America and with them spread infectious diseases. During long sea voyages the agents of these diseases increased their diffusion capacity in a suitable environment. Lack of hygiene, fatigue and privations, a diet without vitamins and many persons kept in confined spaces were the essential features of this environment. Sick persons, whose health conditions worsened during the journey to the New World, carried the germs of infectious diseases. The first disease to appear in the New World was smallpox described in 1518 in Hispaniola. From there the disease moved rapidly to Mexico in 1520, exterminating most of the Aztecs, Guatemala and to the territories of Incas from 1525-26, killing most of them and the King himself. The second disease, influenza, appeared in La Isabela, a few years later, causing a heavy epidemic between 1558 and 1559. Other diseases followed such as yellow fever and malaria. So Europeans and these invisible and mortal agents caused enormous destruction of American populations. In fact historians have estimated that beginning from early 1500, in only 50 years the population of Peru and Mexico fell from 60 to 10 million; in the latter country, in one century, the populations fell from an initial 10 million to only 2 million.     

Is there a "best" way to detect and minimize publication bias? An empirical evaluation

Using 14 meta-analyses that included both published (n = 199) and unpublished (n = 50) randomized trials, we evaluated the utility of different analytical approaches to detect, assess robustness, and minimize publication bias in meta-analysis. The rank correlation and graphical tests indicated funnel plot asymmetry in 3 and 7 of the 14 meta-analyses, respectively. The file drawer number estimates using Iyengar-Greenhouse method were between 1.5 and 4.7 times smaller compared to Rosenthal's estimates. The median difference between the Trim and Fill estimates and the actual number of missing studies was 1 (range -4, 6). Weighted estimation methods adjusted for publication bias and provided estimates of intervention effect close to the reference standard, on average. We showed there are differences in the conclusions one would reach clinically based on the different analytical approaches dealing with publication bias. Our results also suggest that the appropriate use of these methods improves the reliability and accuracy of meta-analysis.