119 research outputs found

    Heat stress incident prevalence and tennis matchplay performance at the Australian Open

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    © 2017 Sports Medicine Australia Objectives: To examine the association of wet bulb globe temperature (WBGT) with the occurrence of heat-related incidents and changes in behavioural and matchplay characteristics in men's Grand Slam tennis. Design: On-court calls for trainers, doctors, cooling devices and water, post-match medical consults and matchplay characteristic data were collected from 360 Australian Open matches (first 4 rounds 2014–2016). Methods: Data were referenced against estimated WBGT and categorised into standard zones. Generalised linear models assessed the association of WBGT zone on heat-related medical incidences and matchplay variables. Results: On-court calls for doctor (47% increase per zone, p = 0.001), heat-related events (41%, p = 0.019), cooling devices (53%, p 32 °C and >28 °C, significant increases in heat-related calls (p = 0.019) and calls for cooling devices (p 32 °C) and cooling device callouts (>28 °C). However, few matchplay characteristics were noticeably affected, with only reduced net approaches and increased aces evident in higher estimated WBGT environments

    Crude incidence in two-phase designs in the presence of competing risks.

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    BackgroundIn many studies, some information might not be available for the whole cohort, some covariates, or even the outcome, might be ascertained in selected subsamples. These studies are part of a broad category termed two-phase studies. Common examples include the nested case-control and the case-cohort designs. For two-phase studies, appropriate weighted survival estimates have been derived; however, no estimator of cumulative incidence accounting for competing events has been proposed. This is relevant in the presence of multiple types of events, where estimation of event type specific quantities are needed for evaluating outcome.MethodsWe develop a non parametric estimator of the cumulative incidence function of events accounting for possible competing events. It handles a general sampling design by weights derived from the sampling probabilities. The variance is derived from the influence function of the subdistribution hazard.ResultsThe proposed method shows good performance in simulations. It is applied to estimate the crude incidence of relapse in childhood acute lymphoblastic leukemia in groups defined by a genotype not available for everyone in a cohort of nearly 2000 patients, where death due to toxicity acted as a competing event. In a second example the aim was to estimate engagement in care of a cohort of HIV patients in resource limited setting, where for some patients the outcome itself was missing due to lost to follow-up. A sampling based approach was used to identify outcome in a subsample of lost patients and to obtain a valid estimate of connection to care.ConclusionsA valid estimator for cumulative incidence of events accounting for competing risks under a general sampling design from an infinite target population is derived

    Smokers' interest in a lung cancer screening programme: a national survey in England.

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    Following the recommendation of lung cancer screening in the US, screening committees in several European countries are reviewing the evidence for implementing national programmes. However, inadequate participation from high-risk groups poses a potential barrier to its effectiveness. The present study examined interest in a national lung cancer screening programme and modifiable attitudinal factors that may affect participation by smokers.A population-based survey of English adults (n = 1464; aged 50-70 years) investigated screening intentions in different invitation scenarios, beliefs about lung cancer, early detection and treatment, worry about lung cancer risk, and stigma. Data on smoking status and perceived chances of quitting were also collected, but eligibility for lung screening in the event of a national programme was unknown.Intentions to be screened were high in all three invitation scenarios for both current (≥ 89%) and former (≥ 94%) smokers. However, smokers were less likely to agree that early-stage survival is good (43% vs. 53%; OR: 0.64, 0.46-0.88) or be willing to have surgery for an early stage, screen-detected cancer (84% vs. 94%; OR: 0.38, 0.21-0.68), compared with former smokers. Willingness to have surgery was positively associated with screening intentions; with absolute differences of 25% and 29%. Worry about lung cancer risk was also most common among smokers (48%), and one fifth of respondents thought screening smokers was a waste of NHS money.A national lung cancer screening programme would be well-received in principle. To improve smokers' participation, care should be taken to communicate the survival benefits of early-stage diagnosis, address concerns about surgery, and minimise anxiety and stigma related to lung cancer risk

    The Lung Screen Uptake Trial (LSUT): protocol for a randomised controlled demonstration lung cancer screening pilot testing a targeted invitation strategy for high risk and ‘hard-to-reach’ patients

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    Background Participation in low-dose CT (LDCT) lung cancer screening offered in the trial context has been poor, especially among smokers from socioeconomically deprived backgrounds; a group for whom the risk-benefit ratio is improved due to their high risk of lung cancer. Attracting high risk participants is essential to the success and equity of any future screening programme. This study will investigate whether the observed low and biased uptake of screening can be improved using a targeted invitation strategy. Methods/design A randomised controlled trial design will be used to test whether targeted invitation materials are effective at improving engagement with an offer of lung cancer screening for high risk candidates. Two thousand patients aged 60–75 and recorded as a smoker within the last five years by their GP, will be identified from primary care records and individually randomised to receive either intervention invitation materials (which take a targeted, stepped and low burden approach to information provision prior to the appointment) or control invitation materials. The primary outcome is uptake of a nurse-led ‘lung health check’ hospital appointment, during which patients will be offered a spirometry test, an exhaled carbon monoxide (CO) reading, and an LDCT if eligible. Initial data on demographics (i.e. age, sex, ethnicity, deprivation score) and smoking status will be collected in primary care and analysed to explore differences between attenders and non-attenders with respect to invitation group. Those who attend the lung health check will have further data on smoking collected during their appointment (including pack-year history, nicotine dependence and confidence to quit). Secondary outcomes will include willingness to be screened, uptake of LDCT and measures of informed decision-making to ensure the latter is not compromised by either invitation strategy. Discussion If effective at improving informed uptake of screening and reducing bias in participation, this invitation strategy could be adopted by local screening pilots or a national programme. Trial registration This study was registered with the ISRCTN (International Standard Registered Clinical/soCial sTudy Number : ISRCTN21774741) on the 23rd September 2015 and the NIH ClinicalTrials.gov database (NCT0255810) on the 22nd September 2015

    Comparative performance of lung cancer risk models to define lung screening eligibility in the United Kingdom

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    Abstract: Background: The National Health Service England (NHS) classifies individuals as eligible for lung cancer screening using two risk prediction models, PLCOm2012 and Liverpool Lung Project-v2 (LLPv2). However, no study has compared the performance of lung cancer risk models in the UK. Methods: We analysed current and former smokers aged 40–80 years in the UK Biobank (N = 217,199), EPIC-UK (N = 30,813), and Generations Study (N = 25,777). We quantified model calibration (ratio of expected to observed cases, E/O) and discrimination (AUC). Results: Risk discrimination in UK Biobank was best for the Lung Cancer Death Risk Assessment Tool (LCDRAT, AUC = 0.82, 95% CI = 0.81–0.84), followed by the LCRAT (AUC = 0.81, 95% CI = 0.79–0.82) and the Bach model (AUC = 0.80, 95% CI = 0.79–0.81). Results were similar in EPIC-UK and the Generations Study. All models overestimated risk in all cohorts, with E/O in UK Biobank ranging from 1.20 for LLPv3 (95% CI = 1.14–1.27) to 2.16 for LLPv2 (95% CI = 2.05–2.28). Overestimation increased with area-level socioeconomic status. In the combined cohorts, USPSTF 2013 criteria classified 50.7% of future cases as screening eligible. The LCDRAT and LCRAT identified 60.9%, followed by PLCOm2012 (58.3%), Bach (58.0%), LLPv3 (56.6%), and LLPv2 (53.7%). Conclusion: In UK cohorts, the ability of risk prediction models to classify future lung cancer cases as eligible for screening was best for LCDRAT/LCRAT, very good for PLCOm2012, and lowest for LLPv2. Our results highlight the importance of validating prediction tools in specific countries

    Aging and the neuroeconomics of decision making: A review

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    Book Review: Applied Meta-Analysis With R

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