59 research outputs found
Fit to Study: Reflections on designing and implementing a large-scale randomized controlled trial in secondary schools
Background. The randomised controlled trial (RCT) design is increasingly common among studies seeking good-quality evidence to advance educational neuroscience, but conducting RCTs in schools is challenging. Fit to Study, one of six such trials funded by the Education Endowment Foundation and Wellcome Trust, tested an intervention to increase vigorous physical activity during PE lessons on maths attainment among pupils aged 12â13. This review of designing and conducting an RCT in 104 schools is intended as a resource on which researchers might draw for future studies.
Method. We consider intervention design and delivery; recruitment, retention, trial management, data collection and analysis including ethical considerations and working with evaluators.
Results. Teacher training, intervention delivery and data collection during large-scale RCTs require a flexible approach appropriate to educational settings, which in turn entails planning and resources.
Conclusion. Simple interventions, with few outcome measures and minimal missing data, are preferable to more complex designs
Managing Injuries of the Neck Trial (MINT) : design of a randomised controlled trial of treatments for whiplash associated disorders
Background: A substantial proportion of patients with whiplash injuries develop chronic
symptoms. However, the best treatment of acute injuries to prevent long-term problems is
uncertain. A stepped care treatment pathway has been proposed, in which patients are given advice
and education at their initial visit to the emergency department (ED), followed by review at three
weeks and physiotherapy for those with persisting symptoms. MINT is a two-stage randomised
controlled trial to evaluate two components of such a pathway: 1. use of The Whiplash Book versus
usual advice when patients first attend the emergency department; 2. referral to physiotherapy
versus reinforcement of advice for patients with continuing symptoms at three weeks.
Methods: Evaluation of the Whiplash Book versus usual advice uses a cluster randomised design
in emergency departments of eight NHS Trusts. Eligible patients are identified by clinicians in
participating emergency departments and are sent a study questionnaire within a week of their ED
attendance. Three thousand participants will be included. Patients with persisting symptoms three
weeks after their ED attendance are eligible to join an individually randomised study of
physiotherapy versus reinforcement of the advice given in ED. Six hundred participants will be
randomised. Follow-up is at 4, 8 and 12 months after their ED attendance. Primary outcome is the
Neck Disability Index (NDI), and secondary outcomes include quality of life and time to return to
work and normal activities. An economic evaluation is being carried out.
Conclusion: This paper describes the protocol and operational aspects of a complex intervention
trial based in NHS emergency and physiotherapy departments, evaluating two components of a
stepped-care approach to the treatment of whiplash injuries. The trial uses two randomisations,
with the first stage being cluster randomised and the second individually randomised
A critical re-evaluation of the Thorne-Zytkow object candidate HV 2112
It has been argued in the literature that the star HV 2112 in the Small Magellanic Cloud (SMC) is the first known example of a ThorneâĆ»ytkow object (TĆ»O), a red supergiant with a degenerate neutron core. This claim is based on the star having a high luminosity (logâ(L/Lâ) âł 5), an extremely cool effective temperature, and a surface enriched in in lithium, calcium, and various irp-process elements. In this paper we re-examine this evidence, and present new measurements of the stellar properties. By compiling archival photometry from blue to mid-infrared for HV 2112 and integrating under its spectral energy distribution, we find a bolometric luminosity in the range of logâ(L/Lâ) = 4.70â4.91, lower than that found in previous work and comparable to bright asymptotic giant branch (AGB) stars. We compare a VLT+XSHOOTER spectrum of HV 2112 to other late-type, luminous SMC stars, finding no evidence for enhancements in Rb, Ca, or K, though there does seem to be an enrichment in Li. We therefore conclude that a much more likely explanation for HV 2112 is that it is an intermediate mass (âŒ5âMâ) AGB star. However, from our sample of comparison stars we identify a new TĆ»O candidate, HV 11417, which seems to be enriched in Rb but for which we cannot determine a Li abundance
Spectropolarimetry of the Type Ib Supernova iPTF 13bvn: revealing the complex explosion geometry of a stripped-envelope core-collapse supernova
We present six epochs of spectropolarimetric observations and one epoch of spectroscopy of the Type Ib SN iPTF 13bvn. The epochs of these observations correspond to â10 to +61 d with respect to the r-band light-curve maximum. The continuum is intrinsically polarized to the 0.2â0.4 per cent level throughout the observations, implying asphericities of âŒ10 per cent in the shape of the photosphere. We observe significant line polarization associated with the spectral features of Ca II IR3, He I/Na I D, He I λλ6678, 7065, Fe II λ4924 and O I λ7774. We propose that an absorption feature at âŒ6200âĂ
, usually identified as Si II λ6355, is most likely to be high-velocity Hâα at â16â400âkmâsâ1. Two distinctly polarized components, separated in velocity, are detected for both He I/Na I D and Ca II IR3 , indicating the presence of two discrete line-forming regions in the ejecta in both radial velocity space and in the plane of the sky. We use the polarization of He I λ5876 as a tracer of sources of non-thermal excitation in the ejecta; finding that the bulk of the radioactive nickel was constrained to lie interior to âŒ50â65âperâcent of the ejecta radius. The observed polarization is also discussed in the context of the possible progenitor system of iPTF 13bvn, with our observations favouring the explosion of a star with an extended, distorted envelope rather than a compact WolfâRayet star
Head Position in Stroke Trial (HeadPoST)- sitting-up vs lying-flat positioning of patients with acute stroke: study protocol for a cluster randomised controlled trial
Background
Positioning a patient lying-flat in the acute phase of ischaemic stroke may improve recovery and reduce disability, but such a possibility has not been formally tested in a randomised trial. We therefore initiated the Head Position in Stroke Trial (HeadPoST) to determine the effects of lying-flat (0°) compared with sitting-up (â„30°) head positioning in the first 24 hours of hospital admission for patients with acute stroke.
Methods/Design
We plan to conduct an international, cluster randomised, crossover, open, blinded outcome-assessed clinical trial involving 140 study hospitals (clusters) with established acute stroke care programs. Each hospital will be randomly assigned to sequential policies of lying-flat (0°) or sitting-up (â„30°) head position as a âbusiness as usualâ stroke care policy during the first 24 hours of admittance. Each hospital is required to recruit 60 consecutive patients with acute ischaemic stroke (AIS), and all patients with acute intracerebral haemorrhage (ICH) (an estimated average of 10), in the first randomised head position policy before crossing over to the second head position policy with a similar recruitment target. After collection of in-hospital clinical and management data and 7-day outcomes, central trained blinded assessors will conduct a telephone disability assessment with the modified Rankin Scale at 90 days. The primary outcome for analysis is a shift (defined as improvement) in death or disability on this scale. For a cluster size of 60 patients with AIS per intervention and with various assumptions including an intracluster correlation coefficient of 0.03, a sample size of 16,800 patients at 140 centres will provide 90 % power (α 0.05) to detect at least a 16 % relative improvement (shift) in an ordinal logistic regression analysis of the primary outcome. The treatment effect will also be assessed in all patients with ICH who are recruited during each treatment study period.
Discussion
HeadPoST is a large international clinical trial in which we will rigorously evaluate the effects of different head positioning in patients with acute stroke.
Trial registration
ClinicalTrials.gov identifier: NCT02162017 (date of registration: 27 April 2014); ANZCTR identifier: ACTRN12614000483651 (date of registration: 9 May 2014). Protocol version and date: version 2.2, 19 June 2014
Dietary and Lifestyle Patterns in the Spanish Pediatric Population (One to <10 Years Old): Design, Protocol, and Methodology of the EsNuPI Study
The interest in a healthy diet and lifestyle during the early stages of life increased, pointing
out its role in the development of noncommunicable chronic diseases throughout adult life. Dietary
habits and dietary patterns begin to be established in early childhood and persist during adulthood.
Therefore, the EsNuPI (âNutritional Study in Spanish Pediatric Populationâ) study aims to depict the
dietary patterns, physical activity, and sedentary behaviors in Spanish children aged from one to
<10 years old. This prospective, cross-sectional, observational study recruited a total of 1514 children
from Spanish cities with >50,000 inhabitants, stratified by Nielsen areas. Participants were involved
in one face-to-face survey, followed by a telephone survey after at least one week. Information
about dietary intake and habits was obtained using a quantitative food frequency questionnaire
and two 24-h dietary recalls. Physical activity and sedentary behaviors were registered using a
specific questionnaire based on a seven-day record. Data were processed and stratified by categorical
variables to be statistically analyzed in order to meet the study objectives. This study is the first of its kind in a Spanish reference population of this age range and the first to evaluate whether
the consumption of adapted milk formulas and dairy products is associated with healthier dietary
patterns and better diet quality and lifestyles in this group.This research was funded by Instituto Puleva de NutriciĂłn (IPN)
The importance of different frailty domains in a population based sample in England
Background: The aim was to estimate the prevalence of frailty and relative contribution of physical/balance, nutritive, cognitive and sensory frailty to important adverse health states (falls, physical activity levels, outdoor mobility, problems in self-care or usual activities, and lack of energy or accomplishment) in an English cohort by age and sex.
Methods: Analysis of baseline data from a cohort of 9803 community-dwelling participants in a clinical trial. The sample was drawn from a random selection of all people aged 70 or more registered with 63 general practices across England. Data were collected by postal questionnaire. Frailty was measured with the Strawbridge questionnaire. We used cross sectional, multivariate logistic regression to estimate the association between frailty domains and known correlates and adjusted for age. Some models were stratified by sex.
Results: Mean age of participants was 78 years (sd 5.7), range 70 to 101 and 47.5% (4653/9803) were men. The prevalence of overall frailty was 20.7% (2005/9671) and there was no difference in prevalence by sex (Odds Ratio 0.98; 95% Confidence Interval 0.89 to 1.08). Sensory frailty was the most common and this was reported by more men (1823/4586) than women (1469/5056; Odds Ratio for sensory frailty 0.62, 95% Confidence Interval 0.57 to 0.68). Men were less likely than women to have physical or nutritive frailty. Physical frailty had the strongest independent associations with adverse health states. However, sensory frailty was independently associated with falls, less frequent walking, problems in self-care and usual activities, lack of energy and accomplishment.
Conclusions: Physical frailty was more strongly associated with adverse health states, but sensory frailty was much more common. The health gain from intervention for sensory frailty in England is likely to be substantial, particularly for older men. Sensory frailty should be explored further as an important target of intervention to improve health outcomes for older people both at clinical and population level.This article is freely available via Open Access. Click on the Publisher URL to access it via the publisher's site.08/14/41/DH_/Department of Health/United Kingdom
Project number 08/14/41/Health Technology Assessment Programmepre-print, post-print, publisher's version/PD
Evidence of patchy hydrogen reionization from an extreme Lyα trough below redshift six
We report the discovery of an extremely long (âŒ110 Mpc/h) and dark (Ïeffâł7) Lyα trough extending down to zâ5.5 towards the zemâ6.0 quasar ULAS J0148+0600. We use these new data in combination with Lyα forest measurements from 42 quasars at 4.5â€zemâ€6.4 to conduct an updated analysis of the line-of-sight variance in the intergalactic Lyα opacity over 4â€zâ€6. We find that the scatter in transmission among lines of sight near zâŒ6 significantly exceeds theoretical expectations for either a uniform ultraviolet background (UVB) or simple fluctuating UVB models in which the mean free path to ionizing photons is spatially invariant. The data, particularly near zâ5.6-5.8, instead require fluctuations in the volume-weighted hydrogen neutral fraction that are a factor of 3 or more beyond those expected from density variations alone. We argue that these fluctuations are most likely driven by large-scale variations in the mean free path, consistent with expectations for the final stages of inhomogeneous hydrogen reionization. Even by zâ5.6, however, a large fraction of the data are consistent with a uniform UVB, and by zâŒ5 the data are fully consistent with opacity fluctuations arising solely from the density field. This suggests that while reionization may be ongoing at zâŒ6, it has fully completed by zâŒ5
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