497 research outputs found
Introduction: Claiming the Promise of Place-Based Education
Each of the papers in Claiming the Promise of Place-based Education offers a much-needed antidote to the forces that disconnect us from the places we teach, learn, and live in. Taken together, they provide an opportunity to reflect on the power of place in education. We invite you to enjoy the fresh air that the authors of this issue of Occasional Papers have brought with them to share with you
Reporting performance of prognostic models in cancer: a review
<p>Abstract</p> <p>Background</p> <p>Appropriate choice and use of prognostic models in clinical practice require the use of good methods for both model development, and for developing prognostic indices and risk groups from the models. In order to assess reliability and generalizability for use, models need to have been validated and measures of model performance reported. We reviewed published articles to assess the methods and reporting used to develop and evaluate performance of prognostic indices and risk groups from prognostic models.</p> <p>Methods</p> <p>We developed a systematic search string and identified articles from PubMed. Forty-seven articles were included that satisfied the following inclusion criteria: published in 2005; aiming to predict patient outcome; presenting new prognostic models in cancer with outcome time to an event and including a combination of at least two separate variables; and analysing data using multivariable analysis suitable for time to event data.</p> <p>Results</p> <p>In 47 studies, Cox models were used in 94% (44), but the coefficients or hazard ratios for the variables in the final model were reported in only 72% (34). The reproducibility of the derived model was assessed in only 11% (5) of the articles. A prognostic index was developed from the model in 81% (38) of the articles, but researchers derived the prognostic index from the final prognostic model in only 34% (13) of the studies; different coefficients or variables from those in the final model were used in 50% (19) of models and the methods used were unclear in 16% (6) of the articles. Methods used to derive prognostic groups were also poor, with researchers not reporting the methods used in 39% (14 of 36) of the studies and data derived methods likely to bias estimates of differences between risk groups being used in 28% (10) of the studies. Validation of their models was reported in only 34% (16) of the studies. In 15 studies validation used data from the same population and in five studies from a different population. Including reports of validation with external data from publications up to four years following model development, external validation was attempted for only 21% (10) of models. Insufficient information was provided on the performance of models in terms of discrimination and calibration.</p> <p>Conclusions</p> <p>Many published prognostic models have been developed using poor methods and many with poor reporting, both of which compromise the reliability and clinical relevance of models, prognostic indices and risk groups derived from them.</p
Reporting methods in studies developing prognostic models in cancer: a review
Development of prognostic models enables identification of variables that are influential in predicting patient outcome and the use of these multiple risk factors in a systematic, reproducible way according to evidence based methods. The reliability of models depends on informed use of statistical methods, in combination with prior knowledge of disease. We reviewed published articles to assess reporting and methods used to develop new prognostic models in cancer.We developed a systematic search string and identified articles from PubMed. Forty-seven articles were included that satisfied the following inclusion criteria: published in 2005; aiming to predict patient outcome; presenting new prognostic models in cancer with outcome time to an event and including a combination of at least two separate variables; and analysing data using multivariable analysis suitable for time to event data.In 47 studies, prospective cohort or randomised controlled trial data were used for model development in only 33% (15) of studies. In 30% (14) of the studies insufficient data were available, having fewer than 10 events per variable (EPV) used in model development. EPV could not be calculated in a further 40% (19) of the studies. The coding of candidate variables was only reported in 68% (32) of the studies. Although use of continuous variables was reported in all studies, only one article reported using recommended methods of retaining all these variables as continuous without categorisation. Statistical methods for selection of variables in the multivariate modelling were often flawed. A method that is not recommended, namely, using statistical significance in univariate analysis as a pre-screening test to select variables for inclusion in the multivariate model, was applied in 48% (21) of the studies.We found that published prognostic models are often characterised by both use of inappropriate methods for development of multivariable models and poor reporting. In addition, models are limited by the lack of studies based on prospective data of sufficient sample size to avoid overfitting. The use of poor methods compromises the reliability of prognostic models developed to provide objective probability estimates to complement clinical intuition of the physician and guidelines
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Streaming primary urgent care: a prospective approach
Aim: To identify the appropriate service provider attendees of emergency departments (EDs) and walk-in centres (WiCs) in North East London and to match this to local service provision and patient choice.
Design: An anonymous patient survey and a retrospective analysis of a random sample of patient records were performed. A nurse consultant, general practitioner (GP) and pharmacist used the presenting complaints in the patients’ records to independently stream the patient to primary care services, non-National Health Services or ED. Statistical analysis of level of agreement was undertaken. A stakeholder focus group reviewed the results.
Subjects and setting Adult health consumers attending ED and urgent care services in North East London.
Results The health user survey identified younger rather than older users (mean age of 35.6 years – SD 15.5), where 50% had not seen a health professional about their concern, with over 40% unable to obtain a convenient or emergency appointment with their GP. Over a third of the attendees were already receiving treatment and over 40% of these saw their complaint as an emergency. Over half of respondents expected to see a doctor, one-quarter expected to see a nurse and only 1% expected to see a pharmacist across both services, although WiCs are nurse-led services. More respondents expected a prescription from a visit to a WiC, whereas in the ED a third of respondents sought health advice or reassurance.
Conclusion: A number of unscheduled care strategies are, or have just been, developed with the emphasis on moving demand into community-based services. Plurality of services provides service users with a range of alternative access points but can cause duplication of services and repeat attendance. Managing continued increase in emergency and unscheduled care is a challenge. The uncertainties in prospective decision making could be used to inform service development and delivery
Predicting risk of osteoporotic and hip fracture in the United Kingdom: prospective independent and external validation of QFractureScores
Objective To evaluate the performance of the QFractureScores for predicting the 10 year risk of osteoporotic and hip fractures in an independent UK cohort of patients from general practice records
Interplay between Microorganisms and Geochemistry in Geological Carbon Storage
Citation: Kirk, MF, Altman, SJ, Santillan, EFU, Bennett, PC (2016) Interplay between microorganisms and geochemistry in geological carbon storage. International Journal of Greenhouse Gas Control 47, 386-395.Researchers at the Center for Frontiers of Subsurface Energy Security (CFSES) have conducted laboratory and modeling studies to better understand the interplay between microorganisms and geochemistry for geological carbon storage (GCS). We provide evidence of microorganisms adapting to high pressure CO2 conditions and identify factors that may influence survival of cells to CO2 stress. Factors that influenced the ability of cells to survive exposure to high-pressure CO2 in our experiments include mineralogy, the permeability of cell walls and/or membranes, intracellular buffering capacity, and whether cells live planktonically or within biofilm. Column experiments show that, following exposure to acidic water, biomass can remain intact in porous media and continue to alter hydraulic conductivity. Our research also shows that geochemical changes triggered by CO2 injection can alter energy available to populations of subsurface anaerobes and that microbial feedbacks on this effect can influence carbon storage. Our research documents the impact of CO2 on microorganisms and in turn, how subsurface microorganisms can influence GCS. We conclude that microbial presence and activities can have important implications for carbon storage and that microorganisms should not be overlooked in further GCS research
The quality of reports of randomised trials in 2000 and 2006: comparative study of articles indexed in PubMed
Objectives To examine the reporting characteristics and methodological details of randomised trials indexed in PubMed in 2000 and 2006 and assess whether the quality of reporting has improved after publication of the Consolidated Standards of Reporting Trials (CONSORT) Statement in 2001
Chemical and Hydrodynamic Mechanisms for Long-Term Geological Carbon Storage
Geological storage of CO₂ (GCS), also referred to as carbon sequestration, is a critical component for decreasing anthropogenic CO₂ atmospheric emissions. Stored CO₂ will exist as a supercritical phase, most likely in deep, saline, sedimentary reservoirs. Research at the Center for Frontiers of Subsurface Energy Security (CFSES), a Department of Energy, Energy Frontier Research Center, provides insights into the storage process. The integration of pore-scale experiments, molecular dynamics simulations, and study of natural analogue sites has enabled understanding of the efficacy of capillary, solubility, and dissolution trapping of CO₂ for GCS. Molecular dynamics simulations provide insight on relative wetting of supercritical CO₂ and brine hydrophilic and hydrophobic basal surfaces of kaolinite. Column experiments of successive supercritical CO₂/brine flooding with high-resolution X-ray computed tomography imaging show a greater than 10% difference of residual trapping of CO₂ in hydrophobic media compared to hydrophilic media that trapped only 2% of the CO₂. Simulation results suggest that injecting a slug of nanoparticle dispersion into the storage reservoir before starting CO₂ injection could increase the overall efficiency of large-scale storage. We estimate that approximately 22% ± 17% of the initial CO₂ emplaced into the Bravo Dome field site of New Mexico has dissolved into the underlying brine. The rate of CO₂ dissolution may be considered limited over geological timescales. Field observations at the Little Grand Wash fault in Utah suggest that calcite precipitation results in shifts in preferential flow paths of the upward migrating CO₂-saturated-brine. Results of hybrid pore-scale and pore network modeling based on Little Grand Wash fault observations demonstrate that inclusion of realistic pore configurations, flow and transport physics, and geochemistry are needed to enhance our fundamental mechanistic explanations of how calcite precipitation alters flow paths by pore plugging to match the Little Grand Wash fault observations
Next Generation Community Leaders Initiative: Collaborating With Youth to Develop Leaders and Healthier Communities
Central to addressing the social determinants of health and challenges to health equity in the United States is the growing acknowledgement among solution seekers of the importance of cross-sector collaborators and partners. Youth are an underutilized and overlooked partner, especially in vulnerable urban communities, who bring diverse perspectives on their communities. Provided the opportunity and resources (e.g., coaching, compensation, and connections), youth can add value as partners to solve problems and achieve goals to benefit their communities. In this paper we review and discuss the Next Generation Community Leaders initiative (NGCL) a $2.8 million initiative funded by New Jersey Health Initiatives, the statewide grantmaking program of the Robert Wood Johnson Foundation. We also describe findings from an independent evaluation of NGCL that explored how investments in youth through youth-serving organizations benefitted the youth who participated and increased health equity in their communities. Finally, we share 5 principles of youth engagement that we identified through our work as practitioners and scholars
A Patient-Centered Primary Care Practice Approach Using Evidence-Based Quality Improvement: Rationale, Methods, and Early Assessment of Implementation
BACKGROUND: Healthcare systems and their primary care practices are redesigning to achieve goals identified in Patient-Centered Medical Home (PCMH) models such as Veterans Affairs (VA)’s Patient Aligned Care Teams (PACT). Implementation of these models, however, requires major transformation. Evidence-Based Quality Improvement (EBQI) is a multi-level approach for supporting organizational change and innovation spread. OBJECTIVE: To describe EBQI as an approach for promoting VA’s PACT and to assess initial implementation of planned EBQI elements. DESIGN: Descriptive. PARTICIPANTS: Regional and local interdisciplinary clinical leaders, patient representatives, Quality Council Coordinators, practicing primary care clinicians and staff, and researchers from six demonstration site practices in three local healthcare systems in one VA region. INTERVENTION: EBQI promotes bottom-up local innovation and spread within top-down organizational priorities. EBQI innovations are supported by a research-clinical partnership, use continuous quality improvement methods, and are developed in regional demonstration sites. APPROACH: We developed a logic model for EBQI for PACT (EBQI-PACT) with inputs, outputs, and expected outcomes. We describe implementation of logic model outputs over 18 months, using qualitative data from 84 key stakeholders (104 interviews from two waves) and review of study documents. RESULTS: Nearly all implementation elements of the EBQI-PACT logic model were fully or partially implemented. Elements not fully achieved included patient engagement in Quality Councils (4/6) and consistent local primary care practice interdisciplinary leadership (4/6). Fourteen of 15 regionally approved innovation projects have been completed, three have undergone initial spread, five are prepared to spread, and two have completed toolkits that have been pretested in two to three sites and are now ready for external spread. DISCUSSION: EBQI-PACT has been feasible to implement in three participating healthcare systems in one VA region. Further development of methods for engaging patients in care design and for promoting interdisciplinary leadership is needed. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11606-013-2703-y) contains supplementary material, which is available to authorized users
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