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21.
In clinical trials, missing data commonly arise through nonadherence to the randomized treatment or to study procedure. For trials in which recurrent event endpoints are of interests, conventional analyses using the proportional intensity model or the count model assume that the data are missing at random, which cannot be tested using the observed data alone. Thus, sensitivity analyses are recommended. We implement the control‐based multiple imputation as sensitivity analyses for the recurrent event data. We model the recurrent event using a piecewise exponential proportional intensity model with frailty and sample the parameters from the posterior distribution. We impute the number of events after dropped out and correct the variance estimation using a bootstrap procedure. We apply the method to an application of sitagliptin study.  相似文献   
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Objective: To help clarify the effect of gender on the bidirectional relationship between alcohol use and strenuous physical activity in college students. Participants: Five hundred twenty-four (52% female) college students recruited in August 2008 and 2009 and followed up in April 2009 and April 2011, respectively. Methods: Participants reported their alcohol use and strenuous physical activity on 2 occasions (baseline and follow-up) spaced approximately 1 or 2 years apart. Results: For females, alcohol use quantity at baseline was associated with increased strenuous physical activity at 1- and 2-year follow-ups, and alcohol use frequency at baseline was associated with decreased strenuous physical activity at 2-year follow-up. For males, alcohol use frequency at baseline predicted decreased strenuous physical activity at 1-year follow-up. Conclusions: Gender differences may be explained from an eating disorders perspective such that women use physical activity as a compensatory strategy to combat potential weight gain from calories consumed during alcohol use.  相似文献   
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Objective: To investigate sexual orientation differences in college men's motivations for HIV testing. Participants: 665 male college students in the Southeastern United States from 2006 to 2014. Methods: Students completed a survey on HIV risk factors and testing motivations. Logistic regressions were conducted to determine the differences between heterosexual men (HM) and sexual minority men (SMM). Results: SMM were more motivated to get tested by concern over past condomless sex, while HM were more often cited supporting the testing program “on principle” and wanting a free t-shirt. SMM and HM differed in behaviors that impact HIV risk and other demographics. However, differences in testing motivation by concern over past condomless sex or wanting a free t-shirt persisted when controlling for these demographic and behavioral differences. Conclusions: Appropriately designed HIV prevention interventions on college campuses should target SMM's distinct concern over past condomless sex as a testing motivation.  相似文献   
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Background

While the provision of maternity education across the perinatal period can increase the confidence and self-efficacy in childbearing women, there is still thought to be a lack of effective educational resources for parenthood. This study, conducted in Victoria, Australia, investigated women’s experiences of, and attitudes to education communicated in maternity service provision.

Methods

189 women were recruited from a variety of settings to participate in a mixed-methods survey about their experiences of perinatal health service education.

Findings

Of the sample of childbearing women, 153 (81%) reported attending antenatal classes. Women perceived their antenatal education as beneficial, though many women still felt unprepared beyond labour and birth. With respect to the hospital postnatal stay, findings suggested a variation among the content imparted to women across different Victorian maternity services, (e.g. rural women tended to be more dissatisfied with information received in relation to maternal emotional and physical health). Overall, women wished they had been more informed about breastfeeding and settling techniques, while a lack of information relating to social support initiatives for the postnatal period was also indicated. Women reported that they were missing educational and practical reinforcement of mothercraft skills.

Conclusions

There is a need for a reorientation of perinatal health service education. A health promotion approach is suggested as it extends beyond the physical recovery from birth to encompass psychosocial factors; including perinatal morbidities that can disrupt the quality and experience of the transition to parenthood.  相似文献   
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The influence of competition level on referees’ decision-making was investigated. Referees’ decisions in 90 handball games (30 games X 3 competition levels) were observed in different situations related to the advantage rule, and 100 referees from two different levels of expertise were subsequently asked to offer explanations for the competition-level effects from the first part of the study. Results revealed that at the highest level of competition referees intervened less frequently with sporting sanctions, but more frequently with disciplinary sanctions. These effects were apparent mainly in immediate intervention situations and unsuccessful advantage situations, but not in successful situations. Referees explained these effects of competition level in terms of a player competence stereotype, in addition to referees’ different expertise across competition level. The implications of the findings for understanding how status-related stereotypes impact on intervention behavior are discussed.  相似文献   
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This paper chronicles the formation and development of the Global Alliance for Public Relations and Communication Management (GA) up to 2002. It sets the GA's genesis within the context of other internationalisation initiatives undertaken by the wider public relations practitioner community and draws links between the formation of the GA and the emerging phenomenon of globalisation. The paper's intent is to describe the formation of the GA from a historical perspective, to understand the forces that led to its creation and to appreciate the different drivers and motivation of founding members. These factors provide a springboard to consider some of the issues that currently challenge GA, some of which were inherent in the governance model it chose at its inception.  相似文献   
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Two competing and yet complementary philosophical concepts form the foundation for the legal protection of intellectual property – ‘competing’ in that created works protected by copyright are unavailable for unrestricted use by others as a result of the economic monopoly given to the works’ owners, and ‘complementary’ in that the presumption is that works no longer protected by copyright serve as the basis for the creation of new copyrightable works. These unprotected works comprise the ‘public domain,’ which has never been affirmatively defined. In Golan v. Holder (2012), the US Supreme Court concluded that such a realm is constitutionally unimportant. This research contends, however, that the Court's decision is incorrect, that Golan, federal legislation, and international treaties threaten to bring larger and larger portions of cultural and intellectual content under the control of a property regime that does not understand the contradiction inherent in the notion of absolute property rights in intangible goods. The result is that the public domain is under tremendous pressure from those entities which have the most to gain from expanded authorial rights and from a weakened and less inclusive public domain. Citizens thus will have fewer rights to access and freely use their culture as they choose. The eventual significance of this evolution will be that further creativity and innovation will be stifled, the opposite of the intention of intellectual property law. In this article, we develop an affirmative definition of the public domain, which we believe will correct the imbalance in current intellectual property law.  相似文献   
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