145 research outputs found

    Ethics Charter for the Intelligent Information Society (2018)

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    Worldwide Use and Impact of the NASA Astrophysics Data System Digital Library

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    By combining data from the text, citation, and reference databases with data from the ADS readership logs we have been able to create Second Order Bibliometric Operators, a customizable class of collaborative filters which permits substantially improved accuracy in literature queries. Using the ADS usage logs along with membership statistics from the International Astronomical Union and data on the population and gross domestic product (GDP) we develop an accurate model for world-wide basic research where the number of scientists in a country is proportional to the GDP of that country, and the amount of basic research done by a country is proportional to the number of scientists in that country times that country's per capita GDP. We introduce the concept of utility time to measure the impact of the ADS/URANIA and the electronic astronomical library on astronomical research. We find that in 2002 it amounted to the equivalent of 736 FTE researchers, or $250 Million, or the astronomical research done in France. Subject headings: digital libraries; bibliometrics; sociology of science; information retrievalComment: ADS bibcode: 2005JASIS..56...36K This is a portion (The bibliometric properties of article readership information is the other part) of the article: The NASA Astrophysics Data System: Sociology, bibliometrics and impact, which went on-line in the summer of 200

    Corrigendum: A systematic review and economic evaluation of bisphosphonates for the prevention of fragility fractures

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    Abstract Background Fragility fractures are fractures that result from mechanical forces that would not ordinarily result in fracture. Objectives To evaluate the clinical effectiveness and safety of bisphosphonates [alendronic acid (Fosamax® and Fosamax® Once Weekly, Merck Sharp & Dohme Ltd), risedronic acid (Actonel® and Actonel Once a Week®, Warner Chilcott UK Ltd), ibandronic acid (Bonviva®, Roche Products Ltd) and zoledronic acid (Aclasta®, Novartis Pharmaceuticals UK Ltd)] for the prevention of fragility fracture and to assess their cost-effectiveness at varying levels of fracture risk. Data sources For the clinical effectiveness review, six electronic databases and two trial registries were searched: MEDLINE, EMBASE, The Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, Web of Science and BIOSIS Previews, Clinicaltrials.gov and World Health Organization International Clinical Trials Registry Platform. Searches were limited by date from 2008 until September 2014. Review methods A systematic review and network meta-analysis (NMA) of effectiveness studies were conducted. A review of published economic analyses was undertaken and a de novo health economic model was constructed. Discrete event simulation was used to estimate lifetime costs and quality-adjusted life-years (QALYs) for each bisphosphonate treatment strategy and a strategy of no treatment for a simulated cohort of patients with heterogeneous characteristics. The model was populated with effectiveness evidence from the systematic review and NMA. All other parameters were estimated from published sources. A NHS and Personal Social Services perspective was taken, and costs and benefits were discounted at 3.5% per annum. Fracture risk was estimated from patient characteristics using the QFracture® (QFracture-2012 open source revision 38, Clinrisk Ltd, Leeds, UK) and FRAX® (web version 3.9, University of Sheffield, Sheffield, UK) tools. The relationship between fracture risk and incremental net benefit (INB) was estimated using non-parametric regression. Probabilistic sensitivity analysis (PSA) and scenario analyses were used to assess uncertainty. Results Forty-six randomised controlled trials (RCTs) were included in the clinical effectiveness systematic review, with 27 RCTs providing data for the fracture NMA and 35 RCTs providing data for the femoral neck bone mineral density (BMD) NMA. All treatments had beneficial effects on fractures versus placebo, with hazard ratios varying from 0.41 to 0.92 depending on treatment and fracture type. The effects on vertebral fractures and percentage change in BMD were statistically significant for all treatments. There was no evidence of a difference in effect on fractures between bisphosphonates. A statistically significant difference in the incidence of influenza-like symptoms was identified from the RCTs for zoledronic acid compared with placebo. Reviews of observational studies suggest that upper gastrointestinal symptoms are frequently reported in the first month of oral bisphosphonate treatment, but pooled analyses of placebo-controlled trials found no statistically significant difference. A strategy of no treatment was estimated to have the maximum INB for patients with a 10-year QFracture risk under 1.5%, whereas oral bisphosphonates provided maximum INB at higher levels of risk. However, the PSA suggested that there is considerable uncertainty regarding whether or not no treatment is the optimal strategy until the QFracture score is around 5.5%. In the model using FRAX, the mean INBs were positive for all oral bisphosphonate treatments across all risk categories. Intravenous bisphosphonates were estimated to have lower INBs than oral bisphosphonates across all levels of fracture risk when estimated using either QFracture or FRAX. Limitations We assumed that all treatment strategies are viable alternatives across the whole population. Conclusions Bisphosphonates are effective in preventing fragility fractures. However, the benefit-to-risk ratio in the lowest-risk patients may be debatable given the low absolute QALY gains and the potential for adverse events. We plan to extend the analysis to include non-bisphosphonate therapies. Study registration This study is registered as PROSPERO CRD42013006883. Funding The National Institute for Health Research Health Technology Assessment programme

    A randomised controlled trial to assess the clinical effectiveness and cost-effectiveness of alternative treatments to Inhibit VEGF in Age-related choroidal Neovascularisation (IVAN)

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    Towards reducing variations in infant mortality and morbidity : a population-based approach

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    Background: Our aims were (1) to improve understanding of regional variation in early-life mortality rates and the UK’s poor performance in international comparisons; and (2) to identify the extent to which late and moderately preterm (LMPT) birth contributes to early childhood mortality and morbidity. Objective: To undertake a programme of linked population-based research studies to work towards reducing variations in infant mortality and morbidity rates. Design: Two interlinked streams: (1) a detailed analysis of national and regional data sets and (2) establishment of cohorts of LMPT babies and term-born control babies. Setting: Cohorts were drawn from the geographically defined areas of Leicestershire and Nottinghamshire, and analyses were carried out at the University of Leicester. Data sources: For stream 1, national data were obtained from four sources: the Office for National Statistics, NHS Numbers for Babies, Centre for Maternal and Child Enquiries and East Midlands and South Yorkshire Congenital Anomalies Register. For stream 2, prospective data were collected for 1130 LMPT babies and 1255 term-born control babies. Main outcome measures: Detailed analysis of stillbirth and early childhood mortality rates with a particular focus on factors leading to biased or unfair comparison; review of clinical, health economic and developmental outcomes over the first 2 years of life for LMPT and term-born babies. Results: The deprivation gap in neonatal mortality has widened over time, despite government efforts to reduce it. Stillbirth rates are twice as high in the most deprived as in the least deprived decile. Approximately 70% of all infant deaths are the result of either preterm birth or a major congenital abnormality, and these are heavily influenced by mothers’ exposure to deprivation. Births at < 24 weeks’ gestation constitute only 1% of all births, but account for 20% of infant mortality. Classification of birth status for these babies varies widely across England. Risk of LMPT birth is greatest in the most deprived groups within society. Compared with term-born peers, LMPT babies are at an increased risk of neonatal morbidity, neonatal unit admission and poorer long-term health and developmental outcomes. Cognitive and socioemotional development problems confer the greatest long-term burden, with the risk being amplified by socioeconomic factors. During the first 24 months of life each child born LMPT generates approximately £3500 of additional health and societal costs. Conclusions: Health professionals should be cautious in reviewing unadjusted early-life mortality rates, particularly when these relate to individual trusts. When more sophisticated analysis is not possible, babies of < 24 weeks’ gestation should be excluded. Neonatal services should review the care they offer to babies born LMPT to ensure that it is appropriate to their needs. The risk of adverse outcome is low in LMPT children. However, the risk appears higher for some types of antenatal problems and when the mother is from a deprived background

    Evidence for models of diagnostic service provision in the community: literature mapping exercise and focused rapid reviews

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    Background Current NHS policy favours the expansion of diagnostic testing services in community and primary care settings. Objectives Our objectives were to identify current models of community diagnostic services in the UK and internationally and to assess the evidence for quality, safety and clinical effectiveness of such services. We were also interested in whether or not there is any evidence to support a broader range of diagnostic tests being provided in the community. Review methods We performed an initial broad literature mapping exercise to assess the quantity and nature of the published research evidence. The results were used to inform selection of three areas for investigation in more detail. We chose to perform focused reviews on logistics of diagnostic modalities in primary care (because the relevant issues differ widely between different types of test); diagnostic ultrasound (a key diagnostic technology affected by developments in equipment); and a diagnostic pathway (assessment of breathlessness) typically delivered wholly or partly in primary care/community settings. Databases and other sources searched, and search dates, were decided individually for each review. Quantitative and qualitative systematic reviews and primary studies of any design were eligible for inclusion. Results We identified seven main models of service that are delivered in primary care/community settings and in most cases with the possible involvement of community/primary care staff. Not all of these models are relevant to all types of diagnostic test. Overall, the evidence base for community- and primary care-based diagnostic services was limited, with very few controlled studies comparing different models of service. We found evidence from different settings that these services can reduce referrals to secondary care and allow more patients to be managed in primary care, but the quality of the research was generally poor. Evidence on the quality (including diagnostic accuracy and appropriateness of test ordering) and safety of such services was mixed. Conclusions In the absence of clear evidence of superior clinical effectiveness and cost-effectiveness, the expansion of community-based services appears to be driven by other factors. These include policies to encourage moving services out of hospitals; the promise of reduced waiting times for diagnosis; the availability of a wider range of suitable tests and/or cheaper, more user-friendly equipment; and the ability of commercial providers to bid for NHS contracts. However, service development also faces a number of barriers, including issues related to staffing, training, governance and quality control. Limitations We have not attempted to cover all types of diagnostic technology in equal depth. Time and staff resources constrained our ability to carry out review processes in duplicate. Research in this field is limited by the difficulty of obtaining, from publicly available sources, up-to-date information about what models of service are commissioned, where and from which providers. Future work There is a need for research to compare the outcomes of different service models using robust study designs. Comparisons of ‘true’ community-based services with secondary care-based open-access services and rapid access clinics would be particularly valuable. There are specific needs for economic evaluations and for studies that incorporate effects on the wider health system. There appears to be no easy way of identifying what services are being commissioned from whom and keeping up with local evaluations of new services, suggesting a need to improve the availability of information in this area. Funding The National Institute for Health Research Health Services and Delivery Research programme

    The role of hydrogen and fuel cells in the global energy system

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    Hydrogen technologies have experienced cycles of excessive expectations followed by disillusion. Nonetheless, a growing body of evidence suggests these technologies form an attractive option for the deep decarb onisation of global energy systems, and that recent improvements in their cost and performance point towards economic viability as well. This paper is a comprehensive review of the potential role that hydrogen could play in the provision of electricity, h eat, industry, transport and energy storage in a low - carbon energy system, and an assessment of the status of hydrogen in being able to fulfil that potential. The picture that emerges is one of qualified promise: hydrogen is well established in certain nic hes such as forklift trucks, while mainstream applications are now forthcoming. Hydrogen vehicles are available commercially in several countries, and 225,000 fuel cell home heating systems have been sold. This represents a step change from the situation of only five years ago. This review shows that challenges around cost and performance remain, and considerable improvements are still required for hydrogen to become truly competitive. But such competitiveness in the medium - term future no longer seems an unrealistic prospect, which fully justifies the growing interest and policy support for these technologies around the world

    Accurate diagnosis of latent tuberculosis in children, people who are immunocompromised or at risk from immunosuppression and recent arrivals from countries with a high incidence of tuberculosis: systematic review and economic evaluation

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    Modifying Alcohol Consumption to Reduce Obesity (MACRO): development and feasibility trial of a complex community-based intervention for men

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    BackgroundObese men who consume alcohol are at a greatly increased risk of liver disease; those who drink > 14 units of alcohol per week have a 19-fold increased risk of dying from liver disease.ObjectivesTo develop an intervention to reduce alcohol consumption in obese men and to assess the feasibility of a randomised controlled trial (RCT) to investigate its effectiveness.Design of the interventionThe intervention was developed using formative research, public involvement and behaviour change theory. It was organised in two phases, comprising a face-to-face session with trained laypeople (study co-ordinators) followed by a series of text messages. Participants explored how alcohol consumption contributed to weight gain, both through direct calorie consumption and through its effect on increasing food consumption, particularly of high-calorie foodstuffs. Men were encouraged to set goals to reduce their alcohol consumption and to make specific plans to do so. The comparator group received an active control in the form of a conventional alcohol brief intervention. Randomisation was carried out using the secure remote web-based system provided by the Tayside Clinical Trials Unit. Randomisation was stratified by the recruitment method and restricted using block sizes of randomly varying lengths. Members of the public were involved in the development of all study methods.SettingMen were recruited from the community, from primary care registers and by time–space sampling (TSS). The intervention was delivered in community settings such as the participant’s home, community centres and libraries.ParticipantsMen aged 35–64 years who had a body mass index (BMI) of > 30 kg/m2 and who drank > 21 units of alcohol per week.ResultsThe screening methods successfully identified participants meeting the entry criteria. Trial recruitment was successful, with 69 men (36 from 419 approached in primary care, and 33 from 470 approached via TSS) recruited and randomised in 3 months. Of the 69 men randomised, 35 were allocated to the intervention group and 34 to the control group. The analysis was conducted on 31 participants from the intervention group and 30 from the control group. The participants covered a wide range of ages and socioeconomic statuses. The average alcohol consumption of the men recruited was 47.2 units per week, more than twice that of the entry criterion (> 21 units per week). Most (78%) engaged in binge drinking (> 8 units in a session) at least weekly. Almost all (95%) exceeded the threshold for a 19-fold increase in the risk of dying from liver disease (BMI of > 30 kg/m2 and > 14 units of alcohol per week). Despite this, they believed that they were at low risk of harm from alcohol, possibly because they seldom suffered acute harms (e.g. hangovers) and made few visits to a general practitioner or hospital.InterventionThe intervention was delivered with high fidelity. A high follow-up rate was achieved (98%) and the outcomes for the full RCT were measured. A process evaluation showed that participants engaged with the main components of the intervention. The acceptability of the study methods was high.ConclusionsThis feasibility study developed a novel intervention and evaluated all of the stages of a RCT that would test the effectiveness of the intervention. The main stages of a trial were completed successfully: recruitment, randomisation, intervention delivery, follow-up and measurement of study outcomes. Most of the men recruited drank very heavily and were also obese. This places them at a very high risk of liver disease, making them a priority for intervention
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