Observational Study Design in Veterinary Pathology, Part 1: Study Design

Observational studies are the basis for much of our knowledge of veterinary pathology and are highly relevant to the daily practice of pathology. However, recommendations for conducting pathology-based observational studies are not readily available. In part 1 of this series, we offer advice on planning and conducting an observational study with examples from the veterinary pathology literature. Investigators should recognize the importance of creativity, insight, and innovation in devising studies that solve problems and fill important gaps in knowledge. Studies should focus on specific and testable hypotheses, questions, or objectives. The methodology is developed to support these goals. We consider the merits and limitations of different types of analytic and descriptive studies, as well as of prospective vs retrospective enrollment. Investigators should define clear inclusion and exclusion criteria and select adequate numbers of study subjects, including careful selection of the most appropriate controls. Studies of causality must consider the temporal relationships between variables and the advantages of measuring incident cases rather than prevalent cases. Investigators must consider unique aspects of studies based on archived laboratory case material and take particular care to consider and mitigate the potential for selection bias and information bias. We close by discussing approaches to adding value and impact to observational studies. Part 2 of the series focuses on methodology and validation of methods

No reserve in isokinetic cycling power at intolerance during ramp incremental exercise in endurance-trained men.

During whole-body exercise in health, maximal oxygen uptake (V̇O2max) is typically attained at or immediately prior to the limit of tolerance (LoT). At the V̇O2max and LoT of incremental exercise, a fundamental, but unresolved, question is whether maximal evocable power can increase above the task requirement, i.e. whether there is a "power reserve" at the LoT. Using an instantaneous switch from cadence-independent to isokinetic cycle ergometry, we determined maximal evocable power at the limit of ramp-incremental exercise. We hypothesized that in endurance-trained men at LoT, maximal (4s) isokinetic power would not differ from power required by the task. Baseline isokinetic power at 80rpm (PISO; measured at the pedals) and summed integrated EMG from 5 leg muscles (∑iEMG) were measured in 12 endurance-trained men (V̇O2max=4.2±1.0 l•min(-1)). Participants then completed a ramp-incremental exercise test (20-25W•min(-1)), with instantaneous measurement of PISO and ∑iEMG at the LoT. PISO decreased from 788±103W at baseline to 391±72W at LoT, which was not different from the required ramp-incremental flywheel power (352±58W; p>0.05). At LoT, the relative reduction in PISO was greater than the relative reduction in the isokinetic ∑iEMG (50±9 vs. 63±10% of baseline; p<0.05). During maximal ramp incremental exercise in endurance-trained men, maximum voluntary power is not different from the power required by the task, and is consequent to both central and peripheral limitations in evocable power. The absence of a power reserve suggests both the perceptual and physiological limits of maximum voluntary power production are not widely dissociated at LoT in this population

The Infrared Spectral Properties of Magellanic Carbon Stars

The Infrared Spectrograph on the Spitzer Space Telescope observed 184 carbon stars in the Magellanic Clouds. This sample reveals that the dust-production rate (DPR) from carbon stars generally increases with the pulsation period of the star. The composition of the dust grains follows two condensation sequences, with more SiC condensing before amorphous carbon in metal-rich stars, and the order reversed in metal-poor stars. MgS dust condenses in optically thicker dust shells, and its condensation is delayed in more metal-poor stars. Metal-poor carbon stars also tend to have stronger absorption from C2H2 at 7.5 μm. The relation between DPR and pulsation period shows significant apparent scatter, which results from the initial mass of the star, with more massive stars occupying a sequence parallel to lower-mass stars, but shifted to longer periods. Accounting for differences in the mass distribution between the carbon stars observed in the Small and Large Magellanic Clouds reveals a hint of a subtle decrease in the DPR at lower metallicities, but it is not statistically significant. The most deeply embedded carbon stars have lower variability amplitudes and show SiC in absorption. In some cases they have bluer colors at shorter wavelengths, suggesting that the central star is becoming visible. These deeply embedded stars may be evolving off of the asymptotic giant branch and/or they may have non-spherical dust geometries

Internet-based medical education: a realist review of what works, for whom and in what circumstances

http://creativecommons.org/licenses/by/2.0

Randomised controlled trial of GP-led in-hospital management of homeless people ('Pathway')

The study was funded by the National Institute for Health Researc

Observational Study Design in Veterinary Pathology, Part 2: Methodology

Observational studies are a basis for much of our knowledge of veterinary pathology, yet considerations for conducting pathology-based observational studies are not readily available. In part 1 of this series, we offered advice on planning and carrying out an observational study. Part 2 of the series focuses on methodology. Our general recommendations are to consider using already-validated methods, published guidelines, data from primary sources, and quantitative analyses. We discuss 3 common methods in pathology research—histopathologic scoring, immunohistochemistry, and polymerase chain reaction—to illustrate principles of method validation. Some aspects of quality control include use of clear objective grading criteria, validation of key reagents, assessing sample quality, determining specificity and sensitivity, use of technical and biologic negative and positive controls, blinding of investigators, approaches to minimizing operator-dependent variation, measuring technical variation, and consistency in analysis of the different study groups. We close by discussing approaches to increasing the rigor of observational studies by corroborating results with complementary methods, using sufficiently large numbers of study subjects, consideration of the data in light of similar published studies, replicating the results in a second study population, and critical analysis of the study findings

The ‘brand’ of the Catholic Church in England and Wales: challenges and opportunities for communications

This paper considers the concept of ‘brand’ in relation to religious organisations and, in particular, the Catholic Church in England and Wales. It explores the application of marketing and branding concepts to the Church and reports on perceptions of the Church’s brand and identity. The findings show that the Catholic Church in England and Wales has very strong brand equity and high levels of brand loyalty among its members, although conventional marketing language should be avoided due to the sensitivities involved. The findings suggest that the Church could usefully be regarded as a ‘brand community’, akin in many key respects to brand communities in the commercial sphere. It recommends that Church communications could be enhanced by leveraging the brand more effectively as within a true ‘brand community’ for the purpose of encouraging brand loyalty and energising Church members

The REFLECT Statement: Methods and Processes of Creating Reporting Guidelines for Randomized Controlled Trials for Livestock and Food Safety by Modifying the CONSORT Statement

The conduct of randomized controlled trials in livestock with production, health and food-safety outcomes presents unique challenges that may not be adequately reported in trial reports. The objective of this project was to modify the CONSORT (Consolidated Standards of Reporting Trials) statement to reflect the unique aspects of reporting these livestock trials. A 2-day consensus meeting was held on 18–19 November 2008 in Chicago, IL, USA, to achieve the objective. Prior to the meeting, a Web-based survey was conducted to identify issues for discussion. The 24 attendees were biostatisticians, epidemiologists, food-safety researchers, livestock-production specialists, journal editors, assistant editors and associate editors. Prior to the meeting, the attendees completed a Web-based survey indicating which CONSORT statement items may need to be modified to address unique issues for livestock trials. The consensus meeting resulted in the production of the REFLECT (Reporting Guidelines for Randomized Control Trials) statement for livestock and food safety and 22-item checklist. Fourteen items were modified from the CONSORT checklist and an additional sub-item was proposed to address challenge trials. The REFLECT statement proposes new terminology, more consistent with common usage in livestock production, to describe study subjects. Evidence was not always available to support modification to or inclusion of an item. The use of the REFLECT statement, which addresses issues unique to livestock trials, should improve the quality of reporting and design for trials reporting production, health and food-safety outcomes