886 resultados para Comparative effectiveness research


Relevância:

80.00% 80.00%

Publicador:

Resumo:

BACKGROUND The choice of imaging techniques in patients with suspected coronary artery disease (CAD) varies between countries, regions, and hospitals. This prospective, multicenter, comparative effectiveness study was designed to assess the relative accuracy of commonly used imaging techniques for identifying patients with significant CAD. METHODS AND RESULTS A total of 475 patients with stable chest pain and intermediate likelihood of CAD underwent coronary computed tomographic angiography and stress myocardial perfusion imaging by single photon emission computed tomography or positron emission tomography, and ventricular wall motion imaging by stress echocardiography or cardiac magnetic resonance. If ≥1 test was abnormal, patients underwent invasive coronary angiography. Significant CAD was defined by invasive coronary angiography as >50% stenosis of the left main stem, >70% stenosis in a major coronary vessel, or 30% to 70% stenosis with fractional flow reserve ≤0.8. Significant CAD was present in 29% of patients. In a patient-based analysis, coronary computed tomographic angiography had the highest diagnostic accuracy, the area under the receiver operating characteristics curve being 0.91 (95% confidence interval, 0.88-0.94), sensitivity being 91%, and specificity being 92%. Myocardial perfusion imaging had good diagnostic accuracy (area under the curve, 0.74; confidence interval, 0.69-0.78), sensitivity 74%, and specificity 73%. Wall motion imaging had similar accuracy (area under the curve, 0.70; confidence interval, 0.65-0.75) but lower sensitivity (49%, P<0.001) and higher specificity (92%, P<0.001). The diagnostic accuracy of myocardial perfusion imaging and wall motion imaging were lower than that of coronary computed tomographic angiography (P<0.001). CONCLUSIONS In a multicenter European population of patients with stable chest pain and low prevalence of CAD, coronary computed tomographic angiography is more accurate than noninvasive functional testing for detecting significant CAD defined invasively. CLINICAL TRIAL REGISTRATION URL http://www.clinicaltrials.gov. Unique identifier: NCT00979199.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

BACKGROUND CONTEXT Several randomized controlled trials (RCTs) have compared patient outcomes of anterior (cervical) interbody fusion (AIF) with those of total disc arthroplasty (TDA). Because RCTs have known limitations with regard to their external validity, the comparative effectiveness of the two therapies in daily practice remains unknown. PURPOSE This study aimed to compare patient-reported outcomes after TDA versus AIF based on data from an international spine registry. STUDY DESIGN AND SETTING A retrospective analysis of registry data was carried out. PATIENT SAMPLE Inclusion criteria were degenerative disc or disc herniation of the cervical spine treated by single-level TDA or AIF, no previous surgery, and a Core Outcome Measures Index (COMI) completed at baseline and at least 3 months' follow-up. Overall, 987 patients were identified. OUTCOME MEASURES Neck and arm pain relief and COMI score improvement were the outcome measures. METHODS Three separate analyses were performed to compare TDA and AIF surgical outcomes: (1) mimicking an RCT setting, with admission criteria typical of those in published RCTs, a 1:1 matched analysis was carried out in 739 patients; (2) an analysis was performed on 248 patients outside the classic RCT spectrum, that is, with one or more typical RCT exclusion criteria; (3) a subgroup analysis of all patients with additional follow-up longer than 2 years (n=149). RESULTS Matching resulted in 190 pairs with an average follow-up of 17 months that had no residual significant differences for any patient characteristics. Small but statistically significant differences in outcome were observed in favor of TDA, which are potentially clinically relevant. Subgroup analyses of atypical patients and of patients with longer-term follow-up showed no significant differences in outcome between the treatments. CONCLUSIONS The results of this observational study were in accordance with those of the published RCTs, suggesting substantial pain reduction both after AIF and TDA, with slightly greater benefit after arthroplasty. The analysis of atypical patients suggested that, in patients outside the spectrum of clinical trials, both surgical interventions appeared to work to a similar extent to that shown for the cohort in the matched study. Also, in the longer-term perspective, both therapies resulted in similar benefits to the patients.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Early-stage lung cancer incidence among older adults is expected to increase due to demographic trends and CT-based screening, yet optimal treatment of lung cancer in the elderly remains controversial. There are several accepted strategies for treating lung cancer including surgery, conventional radiation, and stereotactic ablative body radiotherapy (SABR). However, there are currently no randomized controlled trials to help distinguish the comparative effectiveness of these various strategies. This is an unfortunate omission as lung cancer causes the most deaths among all cancers in the United States (as well as the entire world). SABR holds particular promise as it is a completely non-invasive, ambulatory technique for achieving cure without an operation, thus avoiding the risks of surgery and the associated pre-operative and post-operative costs. To provide fair view of the potential effect on SABR on controlling lung cancer in the United States, a systematic review of SABR with a focus on its achieved outcomes, toxicities, and comparison to conventional radiation and surgical options is presented. ^

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Whilst shopping malls have been explored at length by critical urban studies, there has been little exploration of their role in restructuring the practice of urban and spatial planning. This article uses the shopping mall as an object of study in the light of the neoliberal trends and post-metropolisation in Southern Europe, with the aim of exploring challenges for urban governance and planning practice and with a focus on the role of the ongoing economic crisis. A threefold exploratory framework – the ‘lost-in-time scenario’, the ‘messianic mall model’ and the ‘(im)mature planning explanation’ – is used to make sense of the local versions of shopping mall development in Lisbon (Portugal) and Palermo (Southern Italy). According to findings, we highlight the clash between the multi-scalar nature of shopping malls and the dominance of the municipal scale in regulatory planning frameworks, and the risk that shopping mall development (at least in Southern Europe) may replicate uneven development patterns, reproducing the pre-conditions of the crisis without helping to overcome it.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

An abundance of comparative survey research argues the presence of economic voting as an individual force in European elections, thereby refuting a possible ecological fallacy. But the hypothesis of economic voting at the aggregate level, with macroeconomics influencing overall electoral outcomes, seems less sure. Indeed, there might be a micrological fallacy at work, with the supposed individual economic vote effect not adding up to a national electoral effect after all. Certainly that would account for the spotty evidence linking macroeconomics and national election outcomes. We examine the possibility of a micrological fallacy through rigorous analysis of a large time-series cross-sectional dataset of European nations. From these results, it becomes clear that the macroeconomy strongly moves national election outcomes, with hard times punishing governing parties, and good times rewarding them. Further, this economy-election connection appears asymmetric, altering under economic crisis. Indeed, we show that economic crisis, defined as negative growth, has much greater electoral effects than positive economic growth. Hard times clearly make governments more accountable to their electorates.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

"Contract no. N00014-77-C-0493; Nr 170-087."

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Using the core aspects of five main models of human resource management (HRM), this article investigates the dominant HRM practices in the Indian manufacturing sector. The evaluation is conducted in the context of the recently liberalized economic environment. In response to ever-increasing levels of globalization of business, the article initially highlights the need for more cross-national comparative HRM research. Then it briefly analyzes the five models of HRM (namely, the `Matching model'; the `Harvard model'; the `Contextual model'; the `5-P model'; and the `European model') and identifies the main research questions emerging from these that could be used to reveal and highlight the HRM practices in different national/regional settings. The findings of the research are based on a questionnaire survey of 137 large Indian firms and 24 in-depth interviews in as many firms. The examination not only helped to present the scenario of HRM practices in the Indian context but also the logic dictating the presence of such practices. The article contributes to the fields of cross-national HRM and industrial relations research. It also has key messages for policy makers and opens avenues for further research.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Despite the increasing popularity of research on intercultural preparation and its effectiveness, research on training for inpatriates has not been developed with the same level of rigour as research on training for expatriates. Furthermore, research on intercultural training hardly ever includes the aspect of preparing for the corporate culture of a company. For expatriates coming from headquarters’ national culture and equipped with a good knowledge of headquarters’ corporate culture, it might be sufficient to address only the national culture of the location abroad. But can the same be said for inpatriates coming from a foreign subsidiary? Therefore the qualitative research of my thesis was aimed at finding out if intercultural training programmes that address only the national culture of the host country are sufficient to prepare inpatriates for working at headquarters. A case study using a German multinational company has been conducted in order to find out what kind of problems and irritations inpatriates at the company’s headquarters perceive at work. In order to determine whether the findings are related to the national or the corporate culture, Hall’s and Hofstede’s approaches to culture were used. The interview analysis produced the following conclusion: Although the researched company promotes standardised worldwide corporate guidelines, there are many differences between headquarters and subsidiaries regarding the interpretation and realisation of these guidelines. These differences cause irritation, confusion and problems for the inpatriates. Therefore an effective intercultural preparation for inpatriates should be tailor-made and take into account the aspect of corporate culture, as well as the specific roles and functions of inpatriates.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Although the importance of dataset fitness-for-use evaluation and intercomparison is widely recognised within the GIS community, no practical tools have yet been developed to support such interrogation. GeoViQua aims to develop a GEO label which will visually summarise and allow interrogation of key informational aspects of geospatial datasets upon which users rely when selecting datasets for use. The proposed GEO label will be integrated in the Global Earth Observation System of Systems (GEOSS) and will be used as a value and trust indicator for datasets accessible through the GEO Portal. As envisioned, the GEO label will act as a decision support mechanism for dataset selection and thereby hopefully improve user recognition of the quality of datasets. To date we have conducted 3 user studies to (1) identify the informational aspects of geospatial datasets upon which users rely when assessing dataset quality and trustworthiness, (2) elicit initial user views on a GEO label and its potential role and (3), evaluate prototype label visualisations. Our first study revealed that, when evaluating quality of data, users consider 8 facets: dataset producer information; producer comments on dataset quality; dataset compliance with international standards; community advice; dataset ratings; links to dataset citations; expert value judgements; and quantitative quality information. Our second study confirmed the relevance of these facets in terms of the community-perceived function that a GEO label should fulfil: users and producers of geospatial data supported the concept of a GEO label that provides a drill-down interrogation facility covering all 8 informational aspects. Consequently, we developed three prototype label visualisations and evaluated their comparative effectiveness and user preference via a third user study to arrive at a final graphical GEO label representation. When integrated in the GEOSS, an individual GEO label will be provided for each dataset in the GEOSS clearinghouse (or other data portals and clearinghouses) based on its available quality information. Producer and feedback metadata documents are being used to dynamically assess information availability and generate the GEO labels. The producer metadata document can either be a standard ISO compliant metadata record supplied with the dataset, or an extended version of a GeoViQua-derived metadata record, and is used to assess the availability of a producer profile, producer comments, compliance with standards, citations and quantitative quality information. GeoViQua is also currently developing a feedback server to collect and encode (as metadata records) user and producer feedback on datasets; these metadata records will be used to assess the availability of user comments, ratings, expert reviews and user-supplied citations for a dataset. The GEO label will provide drill-down functionality which will allow a user to navigate to a GEO label page offering detailed quality information for its associated dataset. At this stage, we are developing the GEO label service that will be used to provide GEO labels on demand based on supplied metadata records. In this presentation, we will provide a comprehensive overview of the GEO label development process, with specific emphasis on the GEO label implementation and integration into the GEOSS.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This article is an introduction to the special issue from the 4th Global Entrepreneurship Monitor Research Conference held at Imperial College Business School, London, in 2010. The article has two objectives. The first is to summarize the history of the GEM consortium, some of the contributions that it has delivered, and some challenges and opportunities ahead. The second is to present a summary of the papers in the context of the utility of GEM data in comparative entrepreneurship research. © 2013 Springer Science+Business Media New York.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

We develop the institutional configuration perspective to understand which national contexts facilitate social entrepreneurship (SE). We confirm joint effects on SE of formal regulatory (government activism), informal cognitive (postmaterialist cultural values), and informal normative (socially supportive cultural norms, or weak-tie social capital) institutions in a multilevel study of 106,484 individuals in 26 nations. We test opposing propositions from the institutional void and institutional support perspectives. Our results underscore the importance of resource support from both formal and informal institutions, and highlight motivational supply side influences on SE. They advocate greater consideration of institutional configurations in institutional theory and comparative entrepreneurship research.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Nursing shortages still exist in the U.S. so it is important to determine factors that influence decisions to pursue nursing as a career. This comparative, correlational research study revealed factors that may contribute to, or deter students from choosing nursing as a career. The purpose of this study was to determine factors that contribute to a career choice for nursing based on the concepts of social cognitive career theory (SCCT), self efficacy, outcome expectations, and personal goals, among senior high school students, final year nursing students, and first year nursing students. Based on the results strategies may be developed to recruit a younger pool of students to the nursing profession and to boost retention efforts among those who already made a career choice in nursing. Data were collected using a three part questionnaire developed by the researcher to obtain demographic information and data about the respondents' self efficacy, outcome expectations, and personal goals with regards to nursing as a career. Point bi-serial correlations were used to determine relationships between the variables. ANOVAs and ANCOVAs were computed to determine differences in self efficacy and outcome expectations, among the three groups. Additional descriptive data determined reasons for and against a choice for nursing as a career. Self efficacy and outcome expectations were significantly correlated to career choice among all three groups. The nursing students had higher self efficacy perceptions than the high school students. There were no significant differences in outcome expectations between the three groups. The main categories identified as reasons for choosing nursing as a career were; (a) caring, (b) career and educational advancement, (c) personal accomplishment, (d) proficiency and love of the medical field. Common categories identified for not choosing nursing as a career were; (a) responsibility, (b) liability, (c) lack of respect, and (d) low salary. Other categories regarding not choosing nursing as a career included; (a) the nursing program and (b) professional (c) alternate career choice options and (d) fear of sickness and death. Findings from this study support the tenets of SCCT and may be used to recruit and retain nurses and develop curricula.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

An abundance of comparative survey research argues the presence of economic voting as an individual force in European elections, thereby refuting a possible ecological fallacy. But the hypothesis of economic voting at the aggregate level, with macroeconomics influencing overall electoral outcomes, seems less sure. Indeed, there might be a micrological fallacy at work, with the supposed individual economic vote effect not adding up to a national electoral effect after all. Certainly that would account for the spotty evidence linking macroeconomics and national election outcomes. We examine the possibility of a micrological fallacy through rigorous analysis of a large time-series cross-sectional dataset of European nations. From these results, it becomes clear that the macroeconomy strongly moves national election outcomes, with hard times punishing governing parties, and good times rewarding them. Further, this economy-election connection appears asymmetric, altering under economic crisis. Indeed, we show that economic crisis, defined as negative growth, has much greater electoral effects than positive economic growth. Hard times clearly make governments more accountable to their electorates.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Background The growing prevalence and associated burden of diet-related non-communicable diseases is a global public health concern. The environments in which people live and work influences their dietary behaviours. Aim The focus of this thesis was on the effectiveness of complex workplace dietary interventions. The comparative effectiveness of a complex workplace environmental dietary modification intervention and an educational intervention were assessed both alone and in combination relative to a control workplace setting. Methods The systematic review was guided by the PRISMA statement. In a cluster controlled trial, four workplaces were purposively allocated to control, nutrition education alone (Education), environmental dietary modification alone (Environment) and nutrition education and environmental dietary modification (Combined intervention). The interventions were guided by the MRC framework. In the control workplace, data were collected at baseline and follow-up. In the intervention related sub-study, the relationships between nutrition knowledge, diet quality and hypertension were examined. Results The systematic review provided limited evidence. In the FCW study, 850 employees aged 18-64 years were recruited at baseline with N(response rate %) in each workplace as follows: Control: 111(72%), Education: 226(71%), Environment: 113(91%), Combined intervention: 400(61%). Complete follow-up data was obtained for 517 employees (61%). There were significant positive changes in dietary intakes of saturated fat(p=0.013), salt(p=0.010) and nutrition knowledge(p=0.034) between baseline and follow-up at 7-9 months in the combined intervention versus the control workplace in the fully adjusted multivariate analysis. Small but significant changes in BMI(-1.2kg/m2 (p=0.047) were also observed in the combined intervention. In the sub-study, nutrition knowledge was positively significantly associated with diet quality and blood pressure but no evidence of a mediation effect of the DASH score was detected between nutrition knowledge and blood pressure. Conclusion This thesis provides critical evidence on the effectiveness of complex workplace dietary interventions in a manufacturing working population.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

O presente trabalho relata e analisa o processo de internacionalização tendo em atenção os antecedentes que conduziram ao sucesso das empresas analisadas. O método utilizado foi a pesquisa qualitativa, e envolveu sete entrevistas individuais realizadas numa pequena e média empresa (PME), a Valart (cinco entrevistas), e duas multinacionais, a Bosch e a Quimialmel (um quadro superior entrevistado em cada uma). Os resultados obtidos foram discutidos à luz da literatura, após a transcrição das entrevistas e codificação dos dados primários recolhidos. Pretendeu-se entender como é que as grandes multinacionais Bosch e Quimialmel alcançaram o seu sucesso a nível internacional, assim como analisar, também, como a Valart cresceu e expandiu-se ao longo do tempo. Foi então realizada uma revisão da literatura em que foram abordados temas como a internacionalização, a globalização, o marketing e a inovação, conceitos relevantes ao desenvolvimento deste estudo, revisão essa completada após o trabalho de campo, seguindo-se o grounded theory. No conteúdo do trabalho também são relatadas as atividades desenvolvidas durante o estágio na Valart, e é feita uma análise da empresa e do produto principal em questão (porta-contentores marítimos ou sideloaders). Assim, com a revisão da literatura e análise dos resultados obtidos foi possível retirar conclusões e tecer recomendações de ação / gestão na Valart, tais como investir em colaboradores especializados, abrir um departamento de marketing interligado com o comercial, e sempre apoiado em ferramentas informáticas que poderão fomentar a inovação. Os antecedentes que guiam as empresas analisadas a uma internacionalização de sucesso, internacionalização essa que tem sido gradual e por fases, nas empresas abordadas, incluem: rede de contactos internacional, competência da força de vendas, investigação e desenvolvimento (I&D) que leva a produtos diferenciados, parcerias com universidades, orientação para o cliente, existência de uma marca forte, estrutura de custos eficiente, e aproveitamento do capital humano interno. Por fim, é relevante referir que a crise interna em Portugal tem sido um fator incentivador da procura de diversificação de mercados a nível internacional. Como resultado deste estudo foi apresentado um artigo na conferência internacional ICERI 2014 (Au-Yong-Oliveira e Coelho, 2014).