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131.
This article describes how a frequentist model averaging approach can be used for concentration–QT analyses in the context of thorough QTc studies. Based on simulations, we have concluded that starting from three candidate model families (linear, exponential, and Emax) the model averaging approach leads to treatment effect estimates that are quite robust with respect to the control of the type I error in nearly all simulated scenarios; in particular, with the model averaging approach, the type I error appears less sensitive to model misspecification than the widely used linear model. We noticed also few differences in terms of performance between the model averaging approach and the more classical model selection approach, but we believe that, despite both can be recommended in practice, the model averaging approach can be more appealing because of some deficiencies of model selection approach pointed out in the literature. We think that a model averaging or model selection approach should be systematically considered for conducting concentration–QT analyses. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
132.
We examined whether adolescent sexual abstinence predicts better adult mental health. 1,917 adolescents, recruited from middle schools at age 13, were surveyed at ages 13, 18, 23, and 29. In bivariate analyses, adolescent sexual abstinence was associated with better mental health at age 29 for females, but not males; three adolescent factors, educational prospects, family bonding, and unconventionality were investigated as explanatory variables of this relationship. The abstinence-mental health relationship was nonsignificant when educational prospects was included in multivariate models, and marginally significant when family bonding and unconventionality were included; all three explanatory factors accounted for significant proportions of the variance in adult mental health. Girls who are uninvolved in school, have weak family backgrounds, and exhibit unconventionality may have poor adult mental health, whether or not they abstain from sex in adolescence. Interventions that strengthen adolescents' connections to families and schools may reduce risk for long-term mental health problems.  相似文献   
133.
One in five students report experimenting with tobacco before the age of 13 and most prevention efforts take place in the school setting. This study measures the effect of a single-lesson tobacco prevention curriculum, conducted by a health education center, focusing on knowledge of tobacco, ability to identify refusal techniques, and intent not to smoke. Data were collected, via electronic keypads, from students visiting a non-school, health education center in Michigan (n = 704 intervention and 85 comparison). Contingency table Chi-squared tests and t-tests demonstrated that a single lesson can improve general knowledge and ability to identify appropriate refusal techniques. Improvement in intent not to smoke was not significant because both groups had very high intent prior to implementation. Similar to results from other programs, multivariate logistic regression of gender, general knowledge, and skill identification revealed that only the skill variable was associated with intent not to smoke at pretest. Recommendations are given for further research and for designing more effective curricula or programs.  相似文献   
134.
Using data from 548 experiments in telephone surveys conductedby the Gallup Organization, we explored how attributes of questionsand respondents moderate response order effects in dichotomouscategorical questions. These effects were predominantly recencyeffects and occurred most in questions that were more difficultto comprehend (especially among respondents with the least education),with response choices that were more difficult to comprehend(because they were complete sentences instead of words or phrasesand because they were not mutually exclusive), and that wereasked after many prior questions. Recency effects were alsomore common in questions that explicitly or implicitly encouragedrespondents to wait until they had heard all the answer choicesbefore formulating a judgment than in questions that inducedrespondents to begin formulating a judgment before all the answerchoices had been read (especially among the least educated respondents).A study of interviewer behavior revealed patterns of pausingbetween and within sentences that help to explain why some typesof questions are especially prone to recency effects and othersare not.  相似文献   
135.
At-work exercises are commonly recommended for computer operators. This randomized control trial assessed adherence, pain and satisfaction after 4 weeks of at-work exercise. Subjects (n=72) were randomized into 3 groups: resistance exercise, stretching, and control. Outcomes included a satisfaction survey, a visual analogue pain scale (VAS), a pain drawing, and the Neck Disability Index (NDI). The VAS, the drawing, and NDI were analyzed together as a composite variate referred to as Pain Impact. Exercise frequency was similar across the 3 groups (median=1.5 times per day). No differences were found between groups on Pain Impact p=0.714) or individual pain variables. Most satisfaction survey item scores did not differ between groups. However, a significant difference between groups on the survey item related to discomfort. The resistance and stretching group differed from the control group with regard to their perception that the exercises were helpful in reducing discomfort in the back and neck (p<0.001). We conclude that most subjects found the resistance and the stretching exercises easy to do, performed them 1 to 2 times daily, and said they reduced discomfort. To determine optimal type and frequency of at-work exercises, further study is needed.  相似文献   
136.
OBJECTIVE: In the current study, the authors assessed whether a new online alcohol-misuse prevention course (College Alc) is more effective at reducing alcohol use and related consequences among drinkers and nondrinkers. PARTICIPANTS: The authors compared incoming college freshmen who reported any past 30-day alcohol use before the beginning of the semester with those who did not. METHOD SUMMARY: The authors randomly assigned students who completed a precollege baseline survey to either complete a 3-hour noncredit version of College Alc or serve as members of a control group. The authors conducted a follow-up survey 3 months later. RESULTS: Findings indicated that among freshmen who were regular drinkers before college, College Alc appeared to reduce the frequency of heavy drinking, drunkenness, and negative alcohol-related consequences. Among freshmen who did not report any past-30-day alcohol use before college, College Alc did not appear to have any beneficial effects. CONCLUSIONS: Results suggest that College Alc may be an effective program for students with a history of alcohol use.  相似文献   
137.
OBJECTIVE: Maryland became the first state to pass a vaccination law requiring college and university students living on campus to obtain a meningococcal vaccination or to sign a waiver refusing vaccination because college students are at increased risk for disease. The authors sought to identify how Maryland colleges addressed the law and determine whether schools were in full compliance. PARTICIPANTS: The authors surveyed 32 college/university administrators via a self-administered questionnaire. METHODS: The authors calculated vaccination and waiver rates and assessed compliance with the law overall and with specific law components. RESULTS: Among 28 participating schools, annual vaccination rates and waiver rates among students during 2000-2004 ranged from 66%-76% and 12%-17%, respectively. Two (7%) schools were compliant with all components of the law. CONCLUSIONS: Mandatory vaccination laws do not ensure compliance at the college and university level. Mandatory reporting, increased education, and collaboration between colleges and universities and public health agencies are needed.  相似文献   
138.
Is Work-Family Policy Use Related to the Gendered Division of Housework?   总被引:6,自引:6,他引:0  
Researchers have proposed that work-family policy use may either reinforce or challenge the existing gendered division of labor within couples, but results from prior studies have been inconclusive. Using data from a regional survey of work and family life, we extend this research by focusing on how housework is divided within couples and by differentiating between traditionally female- and male- typed housework tasks. Results show that among dual-earning women, policy use is not related to share of female- or male-typed tasks. Among dual-earning men, policy use is positively related to share of female-typed tasks and negatively related to share of male-typed tasks. These findings suggest that work-family policy use does not reinforce the gendered division of housework.
Mary C. NoonanEmail:
  相似文献   
139.
Communities across the nation have become increasingly concerned about inhalant use and use of harmful legal products among youth because of increasing prevalence rates and deleterious health consequences from abusing these products. The increasing concern of communities about inhaling and ingesting legal products has been coupled with increasing awareness and concern about ability of youth to access and abuse a variety of other legal retail products. There are few examples of scientifically designed community prevention projects that seek to reduce youth abuse of such legal products. This article describes a community prevention trial that is designed to reduce sales of inhalants and other harmful legal products to youth and demonstrates how the retailer component of the trial can be rigorously evaluated. It also shows how data from youth purchase attempts can complement survey data from retailers.  相似文献   
140.
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