6,411 research outputs found
Progress in prevention of mother-to-child transmission of HIV infection in Ukraine: results from a birth cohort study
Background: Ukraine was the epicentre of the HIV epidemic in Eastern Europe, which has the most rapidly accelerating HIV epidemic world-wide today; national HIV prevalence is currently estimated at 1.6%. Our objective was to evaluate the uptake and effectiveness of interventions for prevention of mother-to-child transmission (PMTCT) over an eight year period within operational settings in Ukraine, within the context of an ongoing birth cohort study.Methods: The European Collaborative Study (ECS) is an ongoing birth cohort study in which HIV-infected pregnant women identified before or during pregnancy or at delivery were enrolled and their infants prospectively followed. Three centres in Ukraine started enrolling in 2000, with a further three joining in September 2006.Results: Of the 3356 women enrolled, 21% (689) reported current or past injecting drug use (IDU). Most women were diagnosed antenatally and of those, the proportion diagnosed in the first/second trimester increased from 47% in 2000/01 (83/178) to 73% (776/1060) in 2006/07 (p < 0.001); intrapartum diagnosis was associated with IDU (Adjusted odds ratio 4.38; 95% CI 3.19-6.02). The percentage of women not receiving any antiretroviral prophylaxis declined from 18% (36/205) in 2001 to 7% in 2007 (61/843) p < 0.001). Use of sdNVP alone substantially declined after 2003, with a concomitant increase in zidovudine prophylaxis. Median antenatal zidovudine prophylaxis duration increased from 24 to 72 days between 2000 and 2007. Elective caesarean section (CS) rates were relatively stable over time and 34% overall. Mother-to-child transmission (MTCT) rates decreased from 15.2% in 2001 (95% CI 10.2-21.4) to 7.0% in 2006 (95% CI 2.6-14.6). In adjusted analysis, MTCT risk was reduced by 43% with elective CS versus vaginal delivery and by 75% with zidovudine versus no prophylaxis.Conclusion: There have been substantial improvements in use of PMTCT interventions in Ukraine, including earlier diagnosis of HIV-infected pregnant women and increasing coverage with antiretroviral prophylaxis and the initial MTCT rate has more than halved. Future research should focus on hard-to-reach populations such as IDU and on missed opportunities for further reducing the MTCT rate
MRC/BHF Heart Protection Study of cholesterol lowering with simvastatin in 20 536 high-risk individuals: a randomised placebocontrolled trial
Background: Throughout the usual LDL cholesterol range in Western populations, lower blood concentrations are associated with lower cardiovascular disease risk. In such populations, therefore, reducing LDL cholesterol may reduce the development of vascular disease, largely irrespective of initial cholesterol concentrations. Methods: 20 536 UK adults (aged 40–80 years) with coronary disease, other occlusive arterial disease, or diabetes were randomly allocated to receive 40 mg simvastatin daily (average compliance: 85%) or matching placebo (average non-study statin use: 17%). Analyses are of the first occurrence of particular events, and compare all simvastatin-allocated versus all placebo-allocated participants. These “intention-to-treat” comparisons assess the effects of about two-thirds (85% minus 17%) taking a statin during the scheduled 5-year treatment period, which yielded an average difference in LDL cholesterol of 1·0 mmol/L (about two-thirds of the effect of actual use of 40 mg simvastatin daily). Primary outcomes were mortality (for overall analyses) and fatal or non-fatal vascular events (for subcategory analyses), with subsidiary assessments of cancer and of other major morbidity. Findings: All-cause mortality was significantly reduced (1328 [12·9%] deaths among 10 269 allocated simvastatin versus 1507 [14·7%] among 10 267 allocated placebo; p=0·0003), due to a highly significant 18% (SE 5) proportional reduction in the coronary death rate (587 [5·7%] vs 707 [6·9%]; p=0·0005), a marginally significant reduction in other vascular deaths (194 [1·9%] vs 230 [2·2%]; p=0·07), and a non-significant reduction in non-vascular deaths (547 [5·3%] vs 570 [5·6%]; p=0·4). There were highly significant reductions of about one-quarter in the first event rate for nonfatal myocardial infarction or coronary death (898 [8·7%] vs 1212 [11·8%]; p<0·0001), for non-fatal or fatal stroke (444 [4·3%] vs 585 [5·7%]; p<0·0001), and for coronary or noncoronary revascularisation (939 [9·1%] vs 1205 [11·7%]; p<0·0001). For the first occurrence of any of these major vascular events, there was a definite 24% (SE 3; 95% CI 19–28) reduction in the event rate (2033 [19·8%] vs 2585 [25·2%] affected individuals; p<0·0001). During the first year the reduction in major vascular events was not significant, but subsequently it was highly significant during each separate year. The proportional reduction in the event rate was similar (and significant) in each subcategory of participant studied, including: those without diagnosed coronary disease who had cerebrovascular disease, or had peripheral artery disease, or had diabetes; men and, separately, women; those aged either under or over 70 years at entry; and—most notably—even those who presented with LDL cholesterol below 3·0 mmol/L (116 mg/dL), or total cholesterol below 5·0 mmol/L (193 mg/dL). The benefits of simvastatin were additional to those of other cardioprotective treatments. The annual excess risk of myopathy with this regimen was about 0·01%. There were no significant adverse effects on cancer incidence or on hospitalisation for any other non-vascular cause. Interpretation: Adding simvastatin to existing treatments safely produces substantial additional benefits for a wide range of high-risk patients, irrespective of their initial cholesterol concentrations. Allocation to 40 mg simvastatin daily reduced the rates of myocardial infarction, of stroke, and of revascularisation by about one-quarter. After making allowance for non-compliance, actual use of this regimen would probably reduce these rates by about one-third. Hence, among the many types of high-risk individual studied, 5 years of simvastatin would prevent about 70–100 people per 1000 from suffering at least one of these major vascular events (and longer treatment should produce further benefit). The size of the 5-year benefit depends chiefly on such individuals' overall risk of major vascular events, rather than on their blood lipid concentrations alone
The Million Women Study: design and characteristics of the study population. The Million Women Study Collaborative Group.
OBJECTIVES: To describe the design of the Million Women Study and the characteristics of the study population. STUDY DESIGN: Population-based cohort study of women aged 50-64 in the UK. SETTING: Women are asked to join the Million Women Study when they are invited to routine screening for breast cancer at 61 of the screening centres of the UK National Health Service Breast Screening Programme (NHSBSP). An estimated 71% of women screened by the NHSBSP return a completed questionnaire. PARTICIPANTS: 800 000 women were recruited between May 1996 and June 1999, and it is planned that an additional 200 000 will be recruited by the year 2000. RESULTS: The characteristics of the first 121 000 women recruited into the Million Women Study are described here. At recruitment 33% of the study population were currently using hormone replacement therapy and 47% had used it at some time. Over half (54%) had used oral contraceptives, and 18% were current smokers at the time of recruitment. Before they were screened 1.4% of the women had been diagnosed with breast cancer in the past, 6% had a mother with a history of breast cancer and 3.7% had a sister with a history of breast cancer. It is estimated that 1 million women will have been recruited by early in the year 2000, and that by the end of the year 2002 there will be 5000 screen-detected breast cancers and 23 000 deaths in the cohort, the majority of which will be attributed to cancer (12 600 deaths) and circulatory disease (8000 deaths). CONCLUSIONS: By the end of the year 2002, the Million Women Study will have sufficient statistical power to detect relative risks of 0.8 or less, or of 1.2 or more in current users compared with never users of hormone replacement therapy for mortality from breast cancer, colorectal cancer, lung and ovarian cancer, ischaemic heart disease and stroke
Intelligent support for group work in collaborative learning environments
The delivery of intelligent support for group work is a complex issue in
collaborative learning environments. This particularly pertains to the construction
of effective groups and assessment of collaboration problems. This is because the
composition of groups can be affected by several variables, and various methods
are desirable for ascertaining the existence of different collaboration problems.
Literature has shown that current collaborative learning environments provide
limited or no support for teachers to cope with these tasks. Considering this and the
increasing use of online collaboration, this research aims to explore solutions for
improving the delivery of support for group work in collaborative learning
environments, and thus to simplify how teachers manage collaborative group work.
In this thesis, three aspects were investigated to achieve this goal. The first
aspect emphasises on proposing a novel approach for group formation based on
students‘ learning styles. The novelty and importance of this approach is the
provision of an automatic grouping method that can tailor to individual students‘
characteristics and fit well into the existing collaborative learning environments.
The evaluation activities comprise the development of an add-on tool and an
undergraduate student experiment, which indicate the feasibility and strength of the
proposed approach — being capable of forming diverse groups that tend to perform
more effectively and efficiently than similar groups for conducting group
discussion tasks.
The second focus of this research relates to the identification of major
group collaboration problems and their causes. A nationwide survey was conducted
that reveals a student perspective on the issue, which current literature fails to
adequately address. Based on the findings from the survey, an XML-based
representation was created that provides a unique perspective on the linkages
between the problems and causes identified.
Finally, the focus was then shifted to the proposal of a novel approach for
diagnosing the major collaboration problems identified. The originality and
significance of this approach lies in the provision of various methods for ascertaining the existence of different collaboration problems identified, based on
student interaction data that result from the group work examined. The evaluation
procedure focused on the development of a supporting tool and several
experiments with a test dataset. The results of the evaluation show that the
feasibility and effectiveness are sustained, to a great extent, for the diagnostic
methods addressed.
Besides these main proposals, this research has explored a multi-agent
architecture to unify all the components derived for intelligently managing online
collaborative learning, which suggests an overarching framework providing
context for other parts of this thesis
Culture, role and group work : a social network analysis perspective on an online collaborative course
This paper discusses the patterns of network dynamics within a multicultural online collaborative learning environment. It analyses the interaction of participants (both students and facilitators) within a discussion board that was established as part of a 3-month online collaborative course. The study employs longitudinal probabilistic social network analysis (SNA) to identify the patterns and trends within the network. It conjectures and tests a set of hypotheses concerning the tendencies towards homophily/heterophily and preferential attachment. The paper presents identified interaction network patterns in relation to cultural differences. It also evaluates network dynamics by considering participant roles and group work in the course under study. Results of social network analyses are reported along with measures of statistical confidence in findings. The potential for extending exploratory SNA methods and visualisation techniques in educational research are discussed here
Exploratory talk within collaborative small groups in mathematics
This report describes one aspect of a wider research study on exploratory talk within collaborative small groups in secondary mathematics lessons. It outlines students’ views of using collaborative activity to learn mathematics. The fuller research study explores the extent to which exploratory talk occurs in collaborative peer groups in secondary mathematics classrooms
Determinants of recovery from post-COVID-19 dyspnoea: analysis of UK prospective cohorts of hospitalised COVID-19 patients and community-based controls
Data sharing statement:
PHOSP-COVID: The protocol, consent form, definition and derivation of clinical characteristics and outcomes, training materials, regulatory documents, requests for data access and other relevant study materials are available online at https://www.phosp.org.
COVIDENCE UK: De-identified participant data will be made available upon reasonable request to the corresponding author.Supplementary data is available online at: https://www.sciencedirect.com/science/article/pii/S2666776223000546?via%3Dihub#appsec1 .Copyright © 2023 The Author(s). Background: The risk factors for recovery from COVID-19 dyspnoea are poorly understood. We investigated determinants of recovery from dyspnoea in adults with COVID-19 and compared these to determinants of recovery from non-COVID-19 dyspnoea. Methods: We used data from two prospective cohort studies: PHOSP-COVID (patients hospitalised between March 2020 and April 2021 with COVID-19) and COVIDENCE UK (community cohort studied over the same time period). PHOSP-COVID data were collected during hospitalisation and at 5-month and 1-year follow-up visits. COVIDENCE UK data were obtained through baseline and monthly online questionnaires. Dyspnoea was measured in both cohorts with the Medical Research Council Dyspnoea Scale. We used multivariable logistic regression to identify determinants associated with a reduction in dyspnoea between 5-month and 1-year follow-up. Findings: We included 990 PHOSP-COVID and 3309 COVIDENCE UK participants. We observed higher odds of improvement between 5-month and 1-year follow-up among PHOSP-COVID participants who were younger (odds ratio 1.02 per year, 95% CI 1.01–1.03), male (1.54, 1.16–2.04), neither obese nor severely obese (1.82, 1.06–3.13 and 4.19, 2.14–8.19, respectively), had no pre-existing anxiety or depression (1.56, 1.09–2.22) or cardiovascular disease (1.33, 1.00–1.79), and shorter hospital admission (1.01 per day, 1.00–1.02). Similar associations were found in those recovering from non-COVID-19 dyspnoea, excluding age (and length of hospital admission). Interpretation: Factors associated with dyspnoea recovery at 1-year post-discharge among patients hospitalised with COVID-19 were similar to those among community controls without COVID-19. Funding: PHOSP-COVID is supported by a grant from the MRC-UK Research and Innovation and the Department of Health and Social Care through the National Institute for Health Research (NIHR) rapid response panel to tackle COVID-19. The views expressed in the publication are those of the author(s) and not necessarily those of the National Health Service (NHS), the NIHR or the Department of Health and Social Care. COVIDENCE UK is supported by the UK Research and Innovation, the National Institute for Health Research, and Barts Charity. The views expressed are those of the authors and not necessarily those of the funders.PHOSP-COVID: This study would not be possible without all the participants who have given their time and support. We thank all the participants and their families. We thank the many research administrators, health-care and social-care professionals who contributed to setting up and delivering the study at all of the 65 NHS trusts/Health boards and 25 research institutions across the UK, as well as all the supporting staff at the NIHR Clinical Research Network, Health Research Authority, Research Ethics Committee, Department of Health and Social Care, Public Health Scotland, and Public Health England, and support from the ISARIC Coronavirus Clinical Characterisation Consortium. We thank Kate Holmes at the NIHR Office for Clinical Research Infrastructure (NOCRI) for her support in coordinating the charities group. The PHOSP-COVID industry framework was formed to provide advice and support in commercial discussions, and we thank the Association of the British Pharmaceutical Industry as well NOCRI for coordinating this. We are very grateful to all the charities that have provided insight to the study: Action Pulmonary Fibrosis, Alzheimer's Research UK, Asthma + Lung UK, British Heart Foundation, Diabetes UK, Cystic Fibrosis Trust, Kidney Research UK, MQ Mental Health, Muscular Dystrophy UK, Stroke Association Blood Cancer UK, McPin Foundations, and Versus Arthritis. We thank the NIHR Leicester Biomedical Research Centre patient and public involvement group and Long Covid Support.
COVIDENCE UK: We thank all participants of COVIDENCE UK, and the following organisations who supported study recruitment: Asthma UK/British Lung Foundation, the British Heart Foundation, the British Obesity Society, Cancer Research UK, Diabetes UK, Future Publishing, Kidney Care UK, Kidney Wales, Mumsnet, the National Kidney Federation, the National Rheumatoid Arthritis Society, the North West London Health Research Register (DISCOVER), Primary Immunodeficiency UK, the Race Equality Foundation, SWM Health, the Terence Higgins Trust, and Vasculitis UK
An Exploration of Communication Strategies for Effectively Organizing and Managing Collaborative Grant Writing Groups
The present research explored approaches to collaborative grant writing, as little is known about the details or range of variation in the processes that are currently deployed by professionals working within this context. Findings were used to build a typology of the roles specific to collaborative grant writing groups, provide a discussion of ideal group composition and leadership, and to identify and suggest ten best practice strategies for organizing and managing group dynamics and tasks during the phases of the collaborative writing process
Methodological challenges for collaborative learning research
Research on collaborative learning, both face-to-face and computer-supported, has thrived in the past 10 years. The studies range from outcome-oriented (individual and group learning) to process-oriented (impact of interaction on learning processes, motivation and organisation of collaboration) to mixed studies. Collaborative learning research is multi-disciplinary. This introduces a multitude of theoretical accounts for collaborative learning, accompanied by a broad spectrum of methods to study processes and outcomes of collaboration. This special issue will provide an overview of methods that are at the core of current research effort, but also identifies opportunities and problems to sensibly combine methods into mixed method approaches
Waiting times for carotid endarterectomy in UK: observational study.
OBJECTIVES: To assess timeliness of carotid endarterectomy services in the United Kingdom. DESIGN: Observational study with follow-up to March 2008. SETTING: UK hospitals performing carotid endarterectomy. PARTICIPANTS: UK surgeons undertaking carotid endarterectomy from December 2005 to December 2007. MAIN OUTCOME MEASURES: Provision and speed of delivery of appropriate assessments of patients; carotid endarterectomy and operative mortality; 30 day postoperative mortality. RESULTS: 240 (61% of those eligible) consultant surgeons took part from 102 (76%) hospitals and trusts. Of 9913 carotid endarterectomies recorded on hospital episode statistics, 5513 (56%) were included. Of the patients who underwent endarterectomy, 83% had a history of transient ischaemic attack or stroke. Of these recently symptomatic patients, 20% had their operation within two weeks of onset of symptoms and 30% waited more than 12 weeks. Operative mortality was 0.5% during the inpatient stay and 1.0% (95% confidence interval 0.7% to 1.3%) by 30 days. CONCLUSION: Only 20% of symptomatic patients had surgery within the two week target time set by the National Institute for Health and Clinical Excellence (NICE). Although operative mortality rates are comparable with those in other countries, some patients might experience disabling or fatal stroke while waiting for surgery and hence not be included in operative statistics. Major improvements in services are necessary to enable early surgery in appropriate patients in order to prevent strokes
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