Rabbits (<i>Oryctolagus cuniculus</i> L.) in coastal dune grasslands

We describe a field experiment for examining the impact of wild rabbits (Oryctolagus cuniculus L.) on the vegetation in two Flemish coastal dune grasslands. When numerous, rabbits had a major impact on the vegetation. This impact can be considered positive in the case of the studied grasslands, as evidenced by a decreasing abundance by dominant grass species and a declining species richness. The decrease of the number of rabbits, due to VHS, may hence negatively affect dune grassland species richness. Introducing large herbivores can be part of the solution for preserving the dune grasslands, and this introduction may even have positive effects on rabbit populations through feeding facilitation

Selection and Presentation of Imaging Figures in the Medical Literature

Background: Images are important for conveying information, but there is no empirical evidence on whether imaging figures are properly selected and presented in the published medical literature. We therefore evaluated the selection and presentation of radiological imaging figures in major medical journals. Methodology/Principal Findings: We analyzed articles published in 2005 in 12 major general and specialty medical journals that had radiological imaging figures. For each figure, we recorded information on selection, study population, provision of quantitative measurements, color scales and contrast use. Overall, 417 images from 212 articles were analyzed. Any comment/hint on image selection was made in 44 (11%) images (range 0–50% across the 12 journals) and another 37 (9%) (range 0–60%) showed both a normal and abnormal appearance. In 108 images (26%) (range 0–43%) it was unclear whether the image came from the presented study population. Eighty-three images (20%) (range 0–60%) had any quantitative or ordered categorical value on a measure of interest. Information on the distribution of the measure of interest in the study population was given in 59 cases. For 43 images (range 0–40%), a quantitative measurement was provided for the depicted case and the distribution of values in the study population was also available; in those 43 cases there was no over-representation of extreme than average cases (p = 0.37). Significance: The selection and presentation of images in the medical literature is often insufficiently documented; quantitative data are sparse and difficult to place in context

De aquakultuur met benuttiging van bio-industriële afvalstoffen en thermische effluenten = L'aquaculture utilisant des dechets bio-industriels et des effluents thermiques

The possibility of recycling biodegradable waste materials (manure and waste from agricultural crops) into new proteins was investigated through experiments with various aquaticfood chains. The possibility of increasing the biomass yield through recuperation of the lost energy of thermal effluents was continually taken into consideration. The most promising production procedures which could lead to industrial applificatians are: a) the controlled mass production of pickling lobsters (Artemia) in "batch" or "flow through" systems using agricultural wastes, b). the nursery production of edible shell-fish (oysters, Paphia pullastra clams) using microscopic algae which were grown on manure. Units were designed of both types on a semi-industrial scale and were built on the Belgian coast. In conclusion it can also be mentioned that the mass production of water fleas (Daphnia) using manure and agricultural waste gave very encouraging results on a laboratory scale

Can radiographers be trained to triage CT colonography for extracolonic findings?

OBJECTIVES: Radiographers have been shown to be capable CT colonography observers. We evaluated whether radiographers can be trained to triage screening CT colonography for extracolonic findings. METHODS: Eight radiographers participated in a structured training program. They subsequently evaluated extracolonic findings in 280 low-dose CT colonograms (cases). This dataset contained 66 cases with possibly important findings (E3) and 27 cases with probably important findings (E4) [classification based on the highest classified finding (C-RADS)]. The first 40 and last 40 CT colonograms were identical test cases. Immediate feedback was given after each reading, except for test cases. Radiographers triaged cases based on C-RADS classification and indicated the need for a radiologist read. We constructed learning curves for correct case triaging by calculating moving averages. RESULTS: In the final test series, 84/120 (70 %) cases with E3 or E4 findings and 139/200 (70 %) without E3 or E4 findings were correctly triaged. Correct identification of cases with E3 findings improved with training from 46/88 (52 %) to 62/88 (70 %) (P < 0.0001) but not for E4 findings [both 22/32 (69 %) P = 1.00]. CONCLUSIONS: Radiographers improve after training in correctly triaging extracolonic findings at CT colonography but do not reach a high enough accuracy to consider their structural involvement in screening. KEY POINTS: • Radiographers were trained to triage CT colonography for extracolonic findings. • After training, radiographers improved sensitivity for likely unimportant findings. • After training, radiographers did not improve sensitivity for possibly important findings. • Radiographers should probably not be expected to identify all extracolonic findings

The quality of diagnostic accuracy studies since the STARD statement - Has it improved?

OBJECTIVE: To assess whether the quality of reporting of diagnostic accuracy studies has improved since the publication of the Standards for the Reporting of Diagnostic Accuracy studies (STARD statement). METHODS: The quality of reporting of diagnostic accuracy studies published in 12 medical journals in 2000 (pre-STARD) and 2004 (post-STARD) was evaluated by two reviewers independently. For each article, the number of reported STARD items was counted (range 0 to 25). Differences in completeness of reporting between articles published in 2000 and 2004 were analyzed, using multilevel analyses. RESULTS: We included 124 articles published in 2000 and 141 articles published in 2004. Mean number of reported STARD items was 11.9 (range 3.5 to 19.5) in 2000 and 13.6 (range 4.0 to 21.0) in 2004, an increase of 1.81 items (95% CI: 0.61 to 3.01). Articles published in 2004 reported the following significantly more often: methods for calculating test reproducibility of the index test (16% vs 35%); distribution of the severity of disease and other diagnoses (23% vs 53%); estimates of variability of diagnostic accuracy between subgroups (39% vs 60%); and a flow diagram (2% vs 12%). CONCLUSIONS: The quality of reporting of diagnostic accuracy studies has improved slightly over time, without a more pronounced effect in journals that adopted the STARD statement. As there is still room for improvement, editors should mention the use of the STARD statement as a requirement in their guidelines for authors, and instruct reviewers to check the STARD items. Authors should include a flow diagram in their manuscrip

Using patient management as a surrogate for patient health outcomes in diagnostic test evaluation

<p>Abstract</p> <p>Background</p> <p>Before a new test is introduced in clinical practice, evidence is needed to demonstrate that its use will lead to improvements in patient health outcomes. Studies reporting test accuracy may not be sufficient, and clinical trials of tests that measure patient health outcomes are rarely feasible. Therefore, the consequences of testing on patient management are often investigated as an intermediate step in the pathway. There is a lack of guidance on the interpretation of this evidence, and patient management studies often neglect a discussion of the limitations of measuring patient management as a surrogate for health outcomes.</p> <p>Methods</p> <p>We discuss the rationale for measuring patient management, describe the common study designs and provide guidance about how this evidence should be reported.</p> <p>Results</p> <p>Interpretation of patient management studies relies on the condition that patient management is a valid surrogate for downstream patient benefits. This condition presupposes two critical assumptions: the test improves diagnostic accuracy; and the measured changes in patient management improve patient health outcomes. The validity of this evidence depends on the certainty around these critical assumptions and the ability of the study design to minimise bias. Three common designs are test RCTs that measure patient management as a primary endpoint, diagnostic before-after studies that compare planned patient management before and after testing, and accuracy studies that are extended to report on the actual treatment or further tests received following a positive and negative test result.</p> <p>Conclusions</p> <p>Patient management can be measured as a surrogate outcome for test evaluation if its limitations are recognised. The potential consequences of a positive and negative test result on patient management should be pre-specified and the potential patient benefits of these management changes clearly stated. Randomised comparisons will provide higher quality evidence about differences in patient management using the new test than observational studies. Regardless of the study design used, the critical assumption that patient management is a valid surrogate for downstream patient benefits or harms must be discussed in these studies.</p

Variation in the observed effect of Xpert MTB/RIF testing for tuberculosis on mortality: A systematic review and analysis of trial design considerations [version 2; peer review: 3 approved]

Background: Most studies evaluating the effect of Xpert MTB/RIF testing for tuberculosis (TB) concluded that it did not reduce overall mortality compared to usual care. We conducted a systematic review to assess whether key study design and execution features contributed to earlier identification of patients with TB and decreased pre-treatment loss to follow-up, thereby reducing the potential impact of Xpert MTB/RIF testing. / Methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Scopus for literature published from 1st January 2009 to February 2019. We included all primary intervention studies that had evaluated the effect of Xpert MTB/RIF on mortality compared to usual care in participants with presumptive pulmonary TB. We critically reviewed features of included studies across: Study setting and context, Study population, Participant recruitment and enrolment, Study procedures, and Study follow-up. / Results: We included seven randomised and one non-randomised study. All included studies demonstrated relative reductions in overall mortality in the Xpert MTB/RIF arm ranging from 6% to 40%. However, mortality reduction was reported to be statistically significant in two studies. Study features that could explain the lack of observed effect on mortality included: the higher quality of care at study sites; inclusion of patients with a higher pre-test probability of TB leading to higher than expected empirical rates; performance of additional diagnostic testing not done in usual care leading to increased TB diagnosis or empiric treatment initiation; the recruitment of participants likely to return for follow-up; and involvement of study staff in ensuring adherence with care and follow-up. / Conclusion: Most studies of Xpert MTB/RIF were designed and conducted in a manner that resulted in more patients being diagnosed and treated for TB, minimising the potential difference in mortality Xpert MTB/RIF testing could have achieved compared to usual care