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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
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The prediction error for mixed models can have a conditional or a marginal perspective depending on the research focus. We introduce a novel conditional version of the optimism theorem for mixed models linking the conditional prediction error to covariance penalties for mixed models. Different possibilities for estimating these conditional covariance penalties are introduced. These are bootstrap methods, cross-validation, and a direct approach called Steinian. The behavior of the different estimation techniques is assessed in a simulation study for the binomial-, the t-, and the gamma distribution and for different kinds of prediction error. Furthermore, the impact of the estimation techniques on the prediction error is discussed based on an application to undernutrition in Zambia. 相似文献
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Demography - One of the most consistent patterns in the social sciences is the relationship between sibship size and educational outcomes: those with fewer siblings outperform those with many. The... 相似文献
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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
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Objectives: Attachment insecurity may be more pronounced among young gay and bisexual men (YGBM). Further, attachment insecurity is associated with dysregulated patterns of emotion regulation, which can lead to depression. However, pathways linking attachment insecurity to depression are underexplored among YGBM. Methods: This study used pilot data from N?=?67 YGBM to examine if emotion dysregulation mediated the association between attachment insecurity and depression. Results: Results supported the study hypotheses. Attachment insecurity was associated with emotion dysregulation, which was associated with depression. Conclusion: Findings provide preliminary evidence that emotion regulation training may be a useful approach for addressing depression among YGBM. 相似文献
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“Cruising” infants can only walk using external support to augment their balance. We examined cruisers' understanding of support for upright locomotion under four conditions: cruising over a wooden handrail at chest height, a large gap in the handrail, a wobbly unstable handrail, and an ill‐positioned low handrail. Infants distinguished among the support properties of the handrails with differential attempts to cruise and handrail‐specific forms of haptic exploration and gait modifications. They consistently attempted the wood handrail, rarely attempted the gap, and occasionally attempted the low and wobbly handrails. On the wood and gap handrails, attempt rates matched the probability of cruising successfully, but on the low and wobbly handrails, attempt rates under‐ and overestimated the probability of success, respectively. Haptic exploration was most frequent and varied on the wobbly handrail, and gait modifications—including previously undocumented “knee cruising”—were most frequent and effective on the low handrail. Results are discussed in terms of developmental changes in the meaning of support. 相似文献