1,409 research outputs found
Response-scale heterogeneity in the EQ-5D
This paper discusses two types of response-scale heterogeneity, which may impact upon the EQ-5D. Response-scale heterogeneity in reporting occurs when individuals systematically differ in their use of response scales when responding to self-assessments. This type of heterogeneity is widely observed in relation to other self-assessed measures but is often overlooked with regard to the EQ-5D. Analogous to this, preference elicitation involving the EQ-5D could be subject to a similar type of heterogeneity, where variations across respondents may occur in the interpretations of the levels (response categories) being valued. This response-scale heterogeneity in preference elicitation may differ from variations in preferences for health states, which have been observed in the literature. This paper explores what these forms of response-scale heterogeneity may mean for the EQ-5D and the potential implications for researchers who rely on the instrument as a measure of health and quality of life. We identify situations where they are likely to be problematic and present potential avenues for overcoming these issues
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Visualizing volcanic ash forecasts: scientist and stakeholder decisions using different graphical representations and conflicting forecasts
During volcanic eruptions, Volcanic Ash Advisory Centres issue ash advisories for aviation showing the forecasted outermost extent of the ash cloud. During the 2010 Icelandic volcano Eyjafjallajökull eruption, the UK Met Office produced supplementary forecasts of quantitative ash concentration, due to demand from airlines. Additionally, satellite retrievals of estimated volcanic ash concentration are now available. To test how these additional graphical representations of volcanic ash affect flight decisions, whether users infer uncertainty in graphical forecasts of volcanic ash, and how decisions are made when given conflicting forecasts, a survey was conducted of 25 delegates representing UK research and airline operations dealing with volcanic ash. Respondents were more risk-seeking with safer flight paths and risk-averse with riskier flight paths when given location and concentration forecasts compared to when given only the outermost extent of the ash. Respondents representing operations were more risk-seeking than respondents representing research. Additionally, most respondents' hand-drawn no-fly zones were larger than the areas of unsafe ash concentrations in the forecasts. This conservatism implies that respondents inferred uncertainty from the volcanic ash concentration forecasts. When given conflicting forecasts, respondents became more conservative than when given a single forecast. The respondents were also more risk-seeking with high-risk flight paths and more risk-averse with low-risk flight paths when given conflicting forecasts than when given a single forecast. The results show that concentration forecasts seem to reduce flight cancellations while maintaining safety. Open discussion with the respondents suggested that definitions of "uncertainty" may differ between research and operations
FAR and NEAR Target Dynamic Visual Acuity: A Functional Assessment of Canal and Otolith Performance
Upon their return to earth, astronauts experience the effects of vestibular adaptation to microgravity. The postflight changes in vestibular information processing can affect postural and locomotor stability and may lead to oscillopsia during activities of daily living. However, it is likely that time spent in microgravity affects canal and otolith function differently. As a result, the isolated rotational stimuli used in traditional tests of canal function may fail to identify vestibular deficits after spaceflight. Also, the functional consequences of deficits that are identified often remain unknown. In a gaze control task, the relative contributions of the canal and otolith organs are modulated with viewing distance. The ability to stabilize gaze during a perturbation, on visual targets placed at different distances from the head may therefore provide independent insight into the function of this systems. Our goal was to develop a functional measure of gaze control that can also offer independent information about the function of the canal and otolith organs
Physiological deterioration in the Emergency Department: the SNAP40-ED study
Continuous novel ambulatory monitoring may detect deterioration in Emergency Department (ED) patients more rapidly, prompting treatment and preventing adverse events. Single-centre, open-label, prospective, observational cohort study recruiting high/medium acuity (Manchester triage category 2 and 3) participants, aged over 16 years, presenting to ED. Participants were fitted with a novel wearable monitoring device alongside standard clinical care (wired monitoring and/or manual clinical staff vital sign recording) and observed for up to 4 hours in the ED. Primary outcome was time to detection of deterioration. Two-hundred and fifty (250) patients were enrolled. In 82 patients (32.8%) with standard monitoring (wired monitoring and/or manual clinical staff vital sign recording), deterioration in at least one vital sign was noted during their four-hour ED stay. Overall, the novel device detected deterioration a median of 34 minutes earlier than wired monitoring (Q1, Q3 67,194; n=73, mean difference 39.48, p<0.0001). The novel device detected deterioration a median of 24 minutes (Q1, Q3 2,43; n=42) earlier than wired monitoring and 65 minutes (Q1, Q3 28,114; n=31) earlier than manual vital signs. Deterioration in physiology was common in ED patients. ED staff spent a significant amount of time performing observations and responding to alarms, with many not escalated. The novel device detected deterioration significantly earlier than standard care
Differential item functioning in quality of life measurement:an analysis using anchoring vignettes
Systematic differences in the ways that people use and interpret response categories (differential item functioning, DIF) can introduce bias when using self-assessments to compare health or quality of life across heterogeneous groups. This paper reports on an exploratory analysis involving the use of anchoring vignettes to identify differential item functioning (DIF) in a commonly used measure for assessing health-related quality of life - namely the EQ-5D. Using data from a bespoke (i.e. custom) survey that recruited a representative sample of 4300 respondents from the general Australian population in 2014 and 2015, we find that the assumptions of response consistency (RC) and vignette equivalence (VE) hold in a sub-sample of respondents aged 55–65 years (n = 914), which demonstrates that vignettes can appropriately identify DIF in EQ-5D reporting for this age group. We find that the EQ-5D is indeed subject to DIF, and that failure to account for DIF can lead to conclusions that are misleading when using the instrument to compare health or quality of life across heterogeneous groups. We also provide several important insights in terms of the identifying assumptions of RC and VE. We conclude that the implications of DIF could be of considerable importance, not only for outcomes research, but for funding decisions in healthcare more broadly given the strong reliance on patient-reported outcome measures in economic evaluations for health technology assessment
Life course body mass index and risk of knee osteoarthritis at the age of 53 years: evidence from the 1946 British birth cohort study
Introduction: The authors examined how body mass index (BMI) across life is linked to the risk of midlife knee osteoarthritis (OA), testing whether prolonged exposure to high BMI or high BMI at a particular period has the greatest influence on the risk of knee OA. Methods: A population-based British birth cohort of 3035 men and women underwent clinical examination for knee OA at age 53 years.Heights and weights were measured 10 times from 2 to 53 years. Analyses were stratified by gender and adjusted for occupation and activity levels. Results: The prevalence of knee OA was higher in women than in men (12.9% (n=194) vs 7.4% (n=108)). In men, the association between BMI and later knee OA was evident at 20 years (p=0.038) and remained until 53 years (OR per z-score 1.38 (95% CI 1.11 to 1.71)). In women, there was evidence for an association at 15 years (p=0.003); at 53 years, the OR was 1.89 (95% CI 1.59 to 2.24) per z-score increase in BMI. Changes in BMI from childhood in women and from adolescence in men were also positively associated with knee OA. A structured modelling approach to disentange the way in which BMI is linked to knee OA suggested that prolonged exposure to high BMI throughout adulthood carried the highest risk and that there was no additional risk conferred from adolescence once adult BMI had been accounted for. Conclusion: This study suggests that the risk of knee OA accumulates from exposure to a high BMI through adulthood. <br/
Comparing the effects of sun exposure and vitamin D supplementation on vitamin D insufficiency, and immune and cardio-metabolic function: the Sun Exposure and Vitamin D Supplementation (SEDS) Study
BACKGROUND Adults living in the sunny Australian climate are at high risk of skin cancer, but vitamin D deficiency (defined here as a serum 25-hydroxyvitamin D (25(OH)D) concentration of less than 50 nmol/L) is also common. Vitamin D deficiency may be a risk factor for a range of diseases. However, the optimal strategies to achieve and maintain vitamin D adequacy (sun exposure, vitamin D supplementation or both), and whether sun exposure itself has benefits over and above initiating synthesis of vitamin D, remain unclear. The Sun Exposure and Vitamin D Supplementation (SEDS) Study aims to compare the effectiveness of sun exposure and vitamin D supplementation for the management of vitamin D insufficiency, and to test whether these management strategies differentially affect markers of immune and cardio-metabolic function. METHODS/DESIGN The SEDS Study is a multi-centre, randomised controlled trial of two different daily doses of vitamin D supplementation, and placebo, in conjunction with guidance on two different patterns of sun exposure. Participants recruited from across Australia are aged 18-64 years and have a recent vitamin D test result showing a serum 25(OH)D level of 40-60 nmol/L. DISCUSSION This paper discusses the rationale behind the study design, and considers the challenges but necessity of data collection within a non-institutionalised adult population, in order to address the study aims. We also discuss the challenges of participant recruitment and retention, ongoing engagement of referring medical practitioners and address issues of compliance and participant retention. TRIAL REGISTRATION Australia New Zealand Clinical Trials Registry: ACTRN12613000290796 Registered 14 March 2013
The OMERACT emerging leaders program: The good, the bad, and the future
The Journal of Rheumatology Copyright © 2019. All rights reserved. Objective. To describe the experience of the first OMERACT Emerging Leaders Program (ELP). Methods. A Delphi process identified positive aspects, areas for improvement, and future directions. Core items were defined as essential if they received ≥ 70% ratings. Results. Participants valued relatable/accessible mentors (100%), including an OMERACT Executive mentor (100%), and a support network of peers (90%). Key items for future development were funding support (100%) and developing knowledge about OMERACT processes (90%) and politics (80%). Conclusion. The ELP has the potential to provide targeted training for early career researchers to develop relevant skills for future leadership roles within OMERACT
Growing partnership communities: What experiences of an international institute suggest about developing student-staff partnership in higher education
This article explores the perceptions of participants following the first International Summer Institute (SI) on students as partners in higher education, a four-day professional development experience designed to foster student-staff partnerships. Approximately 9 months after the Institute, 10 participants were interviewed to understand their perceptions of student-staff partnership, and what role the SI played in supporting partnership working. We discuss the key themes that emerged from our interviews, and analyse these participant responses in comparison to responses collected during the 2016 SI. In evaluating our data, we consider the general efficacy of the SI and offer ideas for academic developers interested in supporting partnership work more generally
Consensus of the definitions of the OMERACT glucocorticoid impact core domain set for people with rheumatic and musculoskeletal diseases
Background: The Outcome Measures in Rheumatology (OMERACT) Glucocorticoid (GC) Impact Working Grouphas been working to develop a core domain set to measure the impact of GCs on patients living with rheumaticand musculoskeletal diseases. The mandatory domains previously identified for inclusion in all clinical trialsmeasuring the GC effects include infection, bone fragility, mood disturbance, hypertension, diabetes, weight,fatigue, and mortality. Before progressing to instrument selection, the Working Group sought to establish precisedefinitions of all mandatory domains within the core domain set.Methods: OMERACT methodology was applied with the use of evidence and consensus-based decision making ofall stakeholder groups (patient research partners, health care professionals, clinician researchers, industrymembers and methodologists) to develop detailed definitions for the broad domain, target domain and domaincomponents, taking into consideration sources of variability that could affect measurement of the domain. Theworking group synthesized prior qualitative studies, quantitative work, and results from Delphi rounds, todevelop a rich definition of ‘what’ is to be measured.Results: Between 2021 and 2023, the OMERACT Working Group on GC Impact conducted virtual meetings toestablish domain definitions. First, we mapped each domain onto an OMERACT Core Area. All domains wereprimarily represented within the Pathophysiological Manifestations Core Area, except from Fatigue which wasprimarily Life Impact and Weight which spanned both Core Areas. Sources of variability included cultural factors, age, gender, education level, socioeconomic status, personal experiences, emotional state, and languagebarriers. The domain definitions will form the foundation for instrument selection and the initial step of domain /concept match and content validity in the OMERACT pillar of ‘truth’ before moving on to feasibility anddiscrimination.Conclusion: The OMERACT GC Impact Working Group has developed and agreed upon detailed domain definitions for core domains. Future steps of the working group are to select instruments and develop the core outcom
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