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51.
Marjolein J. E. Greuter Xiang‐Ming Xu Jie‐Bin Lew Evelien Dekker Ernst J. Kuipers Karen Canfell Gerrit A. Meijer Veerle M. H. Coupé 《Risk analysis》2014,34(5):889-910
Several colorectal cancer (CRC) screening models have been developed describing the progression of adenomas to CRC. Currently, there is increasing evidence that serrated lesions can also develop into CRC. It is not clear whether screening tests have the same test characteristics for serrated lesions as for adenomas, but lower sensitivities have been suggested. Models that ignore this type of colorectal lesions may provide overly optimistic predictions of the screen‐induced reduction in CRC incidence. To address this issue, we have developed the Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) model that includes the adenoma‐carcinoma pathway and the serrated pathway to CRC as well as characteristics of colorectal lesions. The model structure and the calibration procedure are described in detail. Calibration resulted in 19 parameter sets for the adenoma‐carcinoma pathway and 13 for the serrated pathway that match the age‐ and sex‐specific adenoma and serrated lesion prevalence in the COlonoscopy versus COlonography Screening (COCOS) trial, Dutch CRC incidence and mortality rates, and a number of other intermediate outcomes concerning characteristics of colorectal lesions. As an example, we simulated outcomes for a biennial fecal immunochemical test screening program and a hypothetical one‐time colonoscopy screening program. Inclusion of the serrated pathway influenced the predicted effectiveness of screening when serrated lesions are associated with lower screening test sensitivity or when they are not removed. To our knowledge, this is the first model that explicitly includes the serrated pathway and characteristics of colorectal lesions. It is suitable for the evaluation of the (cost)effectiveness of potential screening strategies for CRC. 相似文献
52.
Marie Thibaud Frédéric Bloch Caroline Tournoux-Facon Cyril Brèque Anne Sophie Rigaud Beno?t Dugué Gilles Kemoun 《European review of aging and physical activity》2012,9(1):5-15
The objective of this work was to summarise and evaluate the evidence showing that physical activity is a protector factor as regards falls in older people. Relevant studies were identified through a systematic search in the MEDLINE and Cochrane Library, under the keywords of accidental fall/numerical data and risk factors, and with the bibliographies of retrieved papers. The combined odds ratio (OR) [95% confidence interval] for physical activity was 0.75 [0.64, 0.88] with moderate heterogeneity (I 2?=?33%). For fall injury, it was 0.59 [0.47, 0.74] and, for falls in general, it rose to 0.94 [0.76, 1.17] with nil heterogeneity. The combined OR for sedentary factors was 1.14 [1.10, 1.82] with moderate heterogeneity (I 2?=?36%). Regular physical activity in daily life yields significant reduction in falls in older people, especially falls with injuries. 相似文献
53.
Laurie F. DeRose Andrés Salazar-Arango Paúl Corcuera García Montserrat Gas-Aixendri Reynaldo Rivera 《Population studies》2017,71(2):211-228
Efforts to improve child survival in lower-income countries typically focus on fundamental factors such as economic resources and infrastructure provision, even though research from post-industrial countries confirms that family instability has important health consequences. We tested the association between maternal union instability and children’s mortality risk in Africa, Latin America and the Caribbean, and Asia using children’s actual experience of mortality (discrete-time probit hazard models) as well as their experience of untreated morbidity (probit regression). Children of divorced/separated mothers experience compromised survival chances, but children of mothers who have never been in a union generally do not. Among children of partnered women, those whose mothers have experienced prior union transitions have a higher mortality risk. Targeting children of mothers who have experienced union instability—regardless of current union status—may augment ongoing efforts to reduce childhood mortality, especially in Africa and Latin America where union transitions are common. 相似文献
54.
Maria Amérigo Mireya Palavecinos Juan A. García Francisca Román Ítalo Trizano-Hermosilla 《Revista de Psicología Social》2017,32(1):136-163
By adopting a multidimensional approach to environmental attitudes (apathy, anthropocentrism, connectedness and emotional affinity with nature), this study explores the relationships between these dimensions, social dominance orientation (SDO) and political orientation. Two hundred and sixty-two Chilean university students filled out an ad hoc online questionnaire. Two confirmatory factorial analyses showed the four typologies of environmental attitudes and the two factors for SDO, which are labelled group dominance and opposition to equality. Through hierarchical regressions, group dominance showed higher explanatory power of environmental attitudes than political orientation. Furthermore, using the bootstrap procedure we showed that group dominance mediated between political orientation and attitudes of apathy, anthropocentrism and connectedness, while opposition to equality mediated between apathy and emotional affinity. We conclude that SDO is an important variable for measuring political ideology while also providing new nuances when analysing the relationships with environmental attitudes. 相似文献
55.
Clécio S. Ferreira Reinaldo B. Arellano-Valle 《Journal of Statistical Computation and Simulation》2018,88(6):1039-1059
The skew-generalized-normal distribution [Arellano-Valle, RB, Gómez, HW, Quintana, FA. A new class of skew-normal distributions. Comm Statist Theory Methods 2004;33(7):1465–1480] is a class of asymmetric normal distributions, which contains the normal and skew-normal distributions as special cases. The main virtues of this distribution is that it is easy to simulate from and it also supplies a genuine expectation–maximization (EM) algorithm for maximum likelihood estimation. In this paper, we extend the EM algorithm for linear regression models assuming skew-generalized-normal random errors and we develop a diagnostics analyses via local influence and generalized leverage, following Zhu and Lee's approach. This is because Cook's well-known approach would be more complicated to use to obtain measures of local influence. Finally, results obtained for a real data set are reported, illustrating the usefulness of the proposed method. 相似文献
56.
Response‐adaptive designs for binary responses: How to offer patient benefit while being robust to time trends? 下载免费PDF全文
Response‐adaptive randomisation (RAR) can considerably improve the chances of a successful treatment outcome for patients in a clinical trial by skewing the allocation probability towards better performing treatments as data accumulates. There is considerable interest in using RAR designs in drug development for rare diseases, where traditional designs are not either feasible or ethically questionable. In this paper, we discuss and address a major criticism levelled at RAR: namely, type I error inflation due to an unknown time trend over the course of the trial. The most common cause of this phenomenon is changes in the characteristics of recruited patients—referred to as patient drift. This is a realistic concern for clinical trials in rare diseases due to their lengthly accrual rate. We compute the type I error inflation as a function of the time trend magnitude to determine in which contexts the problem is most exacerbated. We then assess the ability of different correction methods to preserve type I error in these contexts and their performance in terms of other operating characteristics, including patient benefit and power. We make recommendations as to which correction methods are most suitable in the rare disease context for several RAR rules, differentiating between the 2‐armed and the multi‐armed case. We further propose a RAR design for multi‐armed clinical trials, which is computationally efficient and robust to several time trends considered. 相似文献
57.
The purpose of this article is to explore the origins of dissent public relations and to establish its emergence in the context of the ancient Greek comedy represented by Aristophanes. Indeed, Attic Comedy (also known as Old Comedy) was the first great example of today’s mass communication, in which political satire was used to dissent and protest against political and social circumstances in fifth-century BC Athens. This situation was conditioned by the Peloponnesian War and its political, economic and social consequences. From this perspective, this article also constitutes an investigation into the intellectual history of public relations, of which Aristophanes can be considered to be one of the first practitioners. 相似文献
58.
Neto Félix Wilks Daniela C. Fonseca Ana Cristina Menezes 《Social indicators research》2019,141(1):463-475
Social Indicators Research - Considerable literature exists on the acculturation and adaptation of immigrants. For the most part, studies looked at their psychological and social adaptation to the... 相似文献
59.
Mella-Méndez Isac Flores-Peredo Rafael Pérez-Torres Jairo Hernández-González Sergio González-Uribe Dino Ulises del Socorro Bolívar-Cimé Beatriz 《Urban Ecosystems》2019,22(6):1061-1070
Urban Ecosystems - Free-ranging domestic dogs are the world most common exotic carnivore species that could negatively interact with the native wildlife as predators, competitors, and disease... 相似文献
60.
We investigate the relationship between homeownership and personal sense of mastery in the transition to adulthood and examine whether three important adult transitions (employment, marriage/cohabitation, and parenthood) moderate the impact of homeownership on mastery. Utilizing the National Longitudinal Survey of Youth—Young Adult Sample (N = 1,609), we estimate change models to assess the direct effects of homeownership on mastery as well as whether this impact is modified by the transition to adult roles. Homeownership increases the sense of mastery among young adults. Homeowners who are unemployed paradoxically receive a boost to mastery not experienced by those who are employed, and homeowners who are parents experience increased mastery, compared to those who do not have children. Owning a home has a positive influence on young adults' sense of mastery during a period when their mastery is in flux and they are accumulating new roles. 相似文献