Fidelity and moderating factors in complex interventions: a case study of a continuum of care program for frail elderly people in health and social care

<p>Abstract</p> <p>Background</p> <p>Prior studies measuring fidelity of complex interventions have mainly evaluated adherence, and not taken factors affecting adherence into consideration. A need for studies that clarify the concept of fidelity and the function of factors moderating fidelity has been emphasized. The aim of the study was to systematically evaluate implementation fidelity and possible factors influencing fidelity of a complex care continuum intervention for frail elderly people.</p> <p>Methods</p> <p>The intervention was a systematization of the collaboration between a nurse with geriatric expertise situated at the emergency department, the hospital ward staff, and a multi-professional team with a case manager in the municipal care services for older people. Implementation was evaluated between September 2008 and May 2010 with observations of work practices, stakeholder interviews, and document analysis according to a modified version of The Conceptual Framework for Implementation Fidelity.</p> <p>Results</p> <p>A total of 16 of the 18 intervention components were to a great extent delivered as planned, while some new components were added to the model. No changes in the frequency or duration of the 18 components were observed, but the dose of the added components varied over time. Changes in fidelity were caused in a complex, interrelated fashion by all the moderating factors in the framework, i.e., context, staff and participant responsiveness, facilitation, recruitment, and complexity.</p> <p>Discussion</p> <p>The Conceptual Framework for Implementation Fidelity was empirically useful and included comprehensive measures of factors affecting fidelity. Future studies should focus on developing the framework with regard to how to investigate relationships between the moderating factors and fidelity over time.</p> <p>Trial registration</p> <p>ClinicalTrials.gov, <a href="http://www.clinicaltrials.gov/ct2/show/NCT01260493">NCT01260493</a>.</p

Demand for Zn2+ in Acid-Secreting Gastric Mucosa and Its Requirement for Intracellular Ca2+

Recent work has suggested that Zn(2+) plays a critical role in regulating acidity within the secretory compartments of isolated gastric glands. Here, we investigate the content, distribution and demand for Zn(2+) in gastric mucosa under baseline conditions and its regulation during secretory stimulation.Content and distribution of zinc were evaluated in sections of whole gastric mucosa using X-ray fluorescence microscopy. Significant stores of Zn(2+) were identified in neural elements of the muscularis, glandular areas enriched in parietal cells, and apical regions of the surface epithelium. In in vivo studies, extraction of the low abundance isotope, (70)Zn(2+), from the circulation was demonstrated in samples of mucosal tissue 24 hours or 72 hours after infusion (250 µg/kg). In in vitro studies, uptake of (70)Zn(2+) from media was demonstrated in isolated rabbit gastric glands following exposure to concentrations as low as 10 nM. In additional studies, demand of individual gastric parietal cells for Zn(2+) was monitored using the fluorescent zinc reporter, fluozin-3, by measuring increases in free intracellular concentrations of Zn(2+) {[Zn(2+)](i)} during exposure to standard extracellular concentrations of Zn(2+) (10 µM) for standard intervals of time. Under resting conditions, demand for extracellular Zn(2+) increased with exposure to secretagogues (forskolin, carbachol/histamine) and under conditions associated with increased intracellular Ca(2+) {[Ca(2+)](i)}. Uptake of Zn(2+) was abolished following removal of extracellular Ca(2+) or depletion of intracellular Ca(2+) stores, suggesting that demand for extracellular Zn(2+) increases and depends on influx of extracellular Ca(2+).This study is the first to characterize the content and distribution of Zn(2+) in an organ of the gastrointestinal tract. Our findings offer the novel interpretation, that Ca(2+) integrates basolateral demand for Zn(2+) with stimulation of secretion of HCl into the lumen of the gastric gland. Similar connections may be detectable in other secretory cells and tissues

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Racial Disparities in Life Expectancy in Brazil: Challenges From a Multiracial Society

Objectives. We calculated life expectancy at birth for Whites, Blacks, and mixed races in Brazil, and decomposed the differences by causes of death. Methods. We used Ministry of Health death records and 2010 Census population data (190 755 799 residents and 1 136 947 deaths). We applied the Arriaga methodology to calculate decomposition of life expectancy by cause of death. We performed sensitivity analyses for underreporting of deaths, missing data, and numerator–denominator bias. Results. Using standard life table methods, female life expectancy was highest for mixed races (78.80 years), followed by Whites (77.54 years), then Blacks (76.32 years). Male life expectancy was highest for Whites (71.10 years) followed closely by mixed races (71.08 years), and lower for Blacks (70.11 years). Homicides contributed the most to the relative life expectancy increase for Whites, and cancer decreased the gap. After adjustment for underreporting, missing data, and numerator–denominator bias, life expectancy was higher for Whites than for Blacks and mixed races. Conclusions. Despite wide socioeconomic differences between Whites and mixed races, standard life table methods showed that mixed races had higher life expectancy than Whites for women, and similar for men. With the increase of multiracial populations, measuring racial disparities in life expectancy will be a fast-growing challenge