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91.
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   
92.
A remarkable out‐migration from Kosovo occurred after the winter 2014/15, raising urgent questions about its underlying drivers and implications for both Kosovo and the destination countries. This article aims at providing a better understanding of key migration triggers and some particularities of the phenomenon. We link our empirically found migration drivers to Hirschman's ( 1970 ) famous exit, voice or loyalty scheme by asking in how far the exit must be understood as the explicit alternative to voicing dissatisfaction with the current situation in the country. According to our results, the recent Kosovar out‐migration is a clear response to weak governance and thus goes beyond the widespread ‘migration‐cum‐remittances’ livelihood practice. In this sense it could be interpreted as a revolt against the political system. With view to policy implications for destination countries, we point at legal travel and migration opportunities as the better solution to channel both voice and exit.  相似文献   
93.
Although cohabitation and childbearing within cohabitation have increased in Europe over recent decades, the variation across Europe remains remarkably wide. Most studies on union formation have not explicitly addressed the role of state policies in the development of cohabitation or discussed how countries have responded to changes in union formation by passing legislation. Here we discuss historical and theoretical issues relevant to the relationship between state policies and union formation and describe policies relating to cohabitation and marriage in nine Western European countries. Drawing on secondary sources and legal documents, we examine the quantity of regulations that mention cohabitation and the approach to cohabitation in 19 policy dimensions. We then place the countries along a continuum, from those that have equalized cohabitation and marriage to those that only regulate marriage. As a whole, this overview raises questions about the changing institution of marriage, as well as the increasing institutionalization of cohabitation.  相似文献   
94.
The present paper makes use of the developmental model of movement between mental positions that was formulated by psychoanalyst Melanie Klein, aimed at understanding the dialogue that takes place between the media and social workers in the field of child welfare, centring around incidents of murder within the family. The basic concept in the paper is that when working with children who are victims of abuse and with their parents, and when reporting on them as well, the feeling of personal control is severely undermined, being associated with the loss of the hallowed social value known as ‘unconditional love of a parent for his child’. The paper illustrates these theoretical ideas by describing two cases that took place in Israel and recommendations are made regarding ways of promoting the dialogue between the professions.  相似文献   
95.
We examined the moderating roles of individualistic and collectivistic cultural orientations and academic achievement on the relation between Chinese adolescents’ shyness and depressive symptoms. A sample of Chinese adolescents (N = 492) from an urban school participated in the study during seventh (T1) and eighth (T2) grades. Adolescents self‐reported their shyness, cultural orientations, and depressive symptoms. The school provided records of their academic achievement. Concurrently, shyness and individualism were positively whereas collectivism and academic achievement were negatively, associated with adolescents’ depressive symptoms. Longitudinally, T1 shyness (but not individualism, collectivism, or academic achievement) predicted T2 depressive symptoms after controlling for stability in depressive symptoms. Concurrent relations between shyness and depressive symptoms were moderated by adolescents’ cultural orientations. Specifically, collectivism was protective whereas individualism was harmful, for shy adolescents’ adjustment. Furthermore, collectivism and academic achievement jointly moderated the relations between shyness and depressive symptoms concurrently and longitudinally. The results suggest that cultural orientations may influence shy adolescents’ depression symptoms through individual‐level self‐evaluation, and indicate that cultural factors and academic achievement need to be considered comprehensively for understanding and improving shy Chinese adolescents’ psychological adjustment.  相似文献   
96.
For survival endpoints in subgroup selection, a score conversion model is often used to convert the set of biomarkers for each patient into a univariate score and using the median of the univariate scores to divide the patients into biomarker‐positive and biomarker‐negative subgroups. However, this may lead to bias in patient subgroup identification regarding the 2 issues: (1) treatment is equally effective for all patients and/or there is no subgroup difference; (2) the median value of the univariate scores as a cutoff may be inappropriate if the sizes of the 2 subgroups are differ substantially. We utilize a univariate composite score method to convert the set of patient's candidate biomarkers to a univariate response score. We propose applying the likelihood ratio test (LRT) to assess homogeneity of the sampled patients to address the first issue. In the context of identification of the subgroup of responders in adaptive design to demonstrate improvement of treatment efficacy (adaptive power), we suggest that subgroup selection is carried out if the LRT is significant. For the second issue, we utilize a likelihood‐based change‐point algorithm to find an optimal cutoff. Our simulation study shows that type I error generally is controlled, while the overall adaptive power to detect treatment effects sacrifices approximately 4.5% for the simulation designs considered by performing the LRT; furthermore, the change‐point algorithm outperforms the median cutoff considerably when the subgroup sizes differ substantially.  相似文献   
97.
Prior work on youth–police relations examines young people's general perceptions of the police, their differential treatment by police officers, and officers' discretion in dealing with youth. Yet researchers have largely neglected the question of how young people attempt to shape these encounters. I address this critical gap, while also incorporating the experiences of “on track” youth and young women—two groups that are not exempt from police contact but traditionally ignored in the youth–police literature. Drawing on semistructured group and individual interviews with 19 black young people in New York City, I investigate the strategies they employ or subscribe to in navigating police contact. Three types of strategies emerged from my analysis: avoidance, management, and symbolic resistance. Avoidance strategies are marked by young people's attempts to preemptively steer clear of officers on the street. Management strategies are employed by young people during police encounters to limit risk or harm, while symbolic resistance is a subtle tactic used by some youth to preserve their dignity in these interactions. This study also considers the gender differences in respondents' approaches and offers new insights into how they assess their police interactions in an era of highly publicized incidents of police brutality.  相似文献   
98.
Bidding above the risk‐neutral Nash equilibrium in first price sealed bid auctions has traditionally been ascribed to risk aversion. Later studies, however, offer other explanations and even argue that risk aversion plays no or a minor role. In a novel experimental design, we directly test the relationship between risk aversion and overbidding by systematically varying the distribution of risk attitudes in auction markets. We find a significant relationship between our measure of risk aversion and overbidding. (JEL D44, C91)  相似文献   
99.
Graduation model interventions represent a new wave of anti‐poverty programming that seeks to offer a sustainable pathway out of poverty. An expanding evidence base points towards positive economic outcomes at household level but little is known about impacts on child well‐being. This paper investigates children’s well‐being in Burundi during and after participation in a graduation model programme using a longitudinal mixed‐methods approach. The programme is found to improve child well‐being, particularly in relation to housing, food security and education. Covariate shocks undermine sustainability of effects but greater knowledge, experience and prioritisation of children’s needs contribute to harnessing improved outcomes.  相似文献   
100.
This article presents data from a study of Syrian diaspora organizations providing assistance to conflict‐affected Syrians in Europe, the Middle East, and North America. Using interview data from leaders in four Syrian diaspora non‐profit organizations, this article examines the social mechanisms used to ensure accountability within the challenging environments where the organizations operate. We find that Syrian diaspora organizations benefit from informal social accountability mechanisms that derive from individuals’ social network ties. Personal, social forms of accountability are particularly valuable to these organizations because these mechanisms help circumvent uncertainty and challenges in the operational environment. These findings reflect an important theme in the extant literature on diaspora philanthropy: diaspora members may have an advantage over other actors because of dense personal networks that make them adept at identifying dependable partners and enforcing agreements even in places where banking and legal systems are fragile.  相似文献   
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