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1.
The federal School and Staffing Survey (SASS) and Teacher Follow-up Survey (TFS) were used to examine the impacts of induction activities on beginning teacher turnover. This study excluded those teachers who moved or left schools for unavoidable and involuntary reasons, a confounding factor in previous research. This analysis revealed that three induction activities are beneficial in significantly reducing turnover rates for beginning teachers: seminars, common planning time, and extra classroom assistance.  相似文献   

2.
Given limited funding for school-based science education, non-school-based programs have been developed at colleges and universities to increase the number of students entering science- and health-related careers and address critical workforce needs. However, few evaluations of such programs have been conducted. We report the design and methods of a controlled trial to evaluate the Stanford Medical Youth Science Program’s Summer Residential Program (SRP), a 25-year-old university-based biomedical pipeline program. This 5-year matched cohort study uses an annual survey to assess educational and career outcomes among four cohorts of students who participate in the SRP and a matched comparison group of applicants who were not chosen to participate in the SRP. Matching on sociodemographic and academic background allows control for potential confounding. This design enables the testing of whether the SRP has an independent effect on educational- and career-related outcomes above and beyond the effects of other factors such as gender, ethnicity, socioeconomic background, and pre-intervention academic preparation. The results will help determine which curriculum components contribute most to successful outcomes and which students benefit most. After 4 years of follow-up, the results demonstrate high response rates from SRP participants and the comparison group with completion rates near 90 %, similar response rates by gender and ethnicity, and little attrition with each additional year of follow-up. This design and methods can potentially be replicated to evaluate and improve other biomedical pipeline programs, which are increasingly important for equipping more students for science- and health-related careers.  相似文献   

3.
ABSTRACT

Ages 10–14 mark a period in which children develop a strong sense of whether science is ‘for them,’ a time that typically coincides with the start of middle school in the United States and their first exposure to more rigorous science classes and testing. Experiences with science in and out of school can shape children's motivation to choose science careers or participate in voluntary science classes later on, for better or worse. We explore the hypothesis that children who engage in more informal educational science experiences at the start of this period are more likely than their peers to obtain and maintain interest, curiosity, and mastery goals in science (together forming a construct called fascination). We measured 983 children's fascination with science at the beginning and middle of sixth grade. We found that the children who participated in informal science during this time were more likely to maintain or have greater fascination than at the start. These findings held while also controlling for many potentially confounding covariates and are robust across subgroups by gender and race/ethnicity. Further, the effects are largest for those children whose family generally supports their learning.  相似文献   

4.
High infant mortality rates among American Indians are disproportionate to state statistics for other races and higher than the national average. These findings prompted a community health center in a large Midwestern city to create and provide an American Indian infant mortality reduction project in the early 1990s. Strategies for program implementation included networking with local organizations, communicating with reservation health clinics throughout the state, educating American Indian mothers and their community about factors contributing to American Indian infant mortality, and providing individual case management to American Indian women and infants. We offer this article for three reasons: This grant project was successful, disparity in rates of infant mortality among peoples of color continues, and a paucity of information exists about the health behaviors of American Indian women.  相似文献   

5.
HVT注苗鸡和未注苗鸡．分别以AIDV强毒接种感染和同居感染,用琼脂扩散试验（AGPT）检测各鸡群不同时期羽囊MDV抗原和抗体。结果显示,HVT苗可使实验鸡羽囊中MDV抗原检出时间推迟,阳性检出率显著降低：而羽囊中MDV抗体检出情况与此正好相反,检出时间早,阳性率高。  相似文献   

6.
The present study investigated differences in the effectiveness of instructors from a variety of departments who taught the same course in both intensive and traditional formats within the same year, while controlling for many confounding variables. Results indicated that intensive courses did not significantly differ from traditional courses in overall instructor ratings on student evaluations of teaching effectiveness when confounding variables were taken into account. Conversely, intensive courses received significantly higher overall course ratings on student evaluations than did traditional courses, even after controlling for class size and probable grade in course. These findings provide further evidence that negative beliefs concerning intensive courses may be unjustified, and intensive courses may be as or more effective than those presented in traditional formats.  相似文献   

7.
Latent growth curve mediation models are increasingly used to assess mechanisms of behavior change. For latent growth mediation model, like any another mediation model, even with random treatment assignment, a critical but untestable assumption for valid and unbiased estimates of the indirect effects is that there should be no omitted variable that confounds indirect effects. One way to address this untestable assumption is to conduct sensitivity analysis to assess whether the inference about an indirect effect would change under varying degrees of confounding bias. We developed a sensitivity analysis technique for a latent growth curve mediation model. We compute the biasing effect of confounding on point and confidence interval estimates of the indirect effects in a structural equation modeling framework. We illustrate sensitivity plots to visualize the effects of confounding on each indirect effect and present an empirical example to illustrate the application of the sensitivity analysis.  相似文献   

8.
This article focuses on improving the instructional quality of student teachers in elementary education. We developed a coaching approach involving classroom observation and appropriate lesson preparation and feedback templates. Using an untreated control group design with pre-test and posttest (n = 198), we answered the question ‘whether student teachers who learned to teach with the new coaching approach achieved a higher level of pedagogical and didactical teaching skills compared to student teachers who did not receive this approach’. The effect variable used was the observation instrument ICALT. We compared the average scores of the control group and the experimental group on the posttest (ANCOVA). The differences found on the posttest, after controlling for the confounding variables, were significant on all ICALT scales. These effect sizes are medium on the scales; ‘Safe climate’, and ‘Clear instruction’, and large on the scales; ‘Classroom management’, ‘Activating pupils’, ‘Adaptive teaching’, and ‘Teaching learning strategies’.  相似文献   

9.
The influence of asynchronous discussion in a virtual learning environment, Blackboard, on subsequent coursework grades was examined with 166 psychology students to determine whether asking questions of the tutor online, and/or reading the questions and the given advice, influenced the grades on the report they were writing. A repeated‐measures quasiexperimental design was used, with and without Blackboard available, to control for confounding variables. The grades on the assignment with Blackboard available were significantly higher than those on the previous assignment (when Blackboard was unavailable). Students who never used Blackboard had significantly lower grades on the assignment than the students who had used it. There was a positive relationship between the number of messages read and the grade achieved on the assignment. Students who read the most discussion board posts wrote significantly better reports (up by 4%) than they had previously. No improvement in grades occurred for the people who read no posts at all. Both the students who asked questions and those who just read the questions and answers (‘lurkers’) ended up with significantly better grades than they had done before Blackboard was introduced.  相似文献   

10.
Little is known about developmental outcomes in midlife of persons who were placed in out-of-home care (OHC) in childhood. Utilizing longitudinal Swedish data from a cohort of more than 14,000 individuals who we can follow from birth (1953) to the age of 55 (2008), this study examines midlife trajectories of social, economic, and health-related disadvantages with a specific focus on the complexity, timing, and duration of disadvantage in individuals with and without childhood experience of OHC. Roughly half of the OHC alumni did not have disadvantaged outcomes in midlife. However, experience of OHC was associated with a two-fold risk for various forms of permanent disadvantage, net of confounding factors. Implications for research, policy, and practice are discussed.  相似文献   

11.
Straus MA 《Child abuse & neglect》2006,30(11):1257-1279
OBJECTIVE: To provide data on the cross-cultural reliability of the Adult Recall Short Form of the Multidimensional Neglectful Behavior Scale (MNBS), and also illustrative validity evidence. The MNBS includes items on four aspects of neglectful behavior: cognitive, emotional, physical, and supervisory. METHOD: The data were obtained by questionnaires completed by a convenience sample of 7179 students at 33 universities in 17 countries. RESULTS: The alpha coefficient of internal consistency for the entire sample was .72. By site, the coefficients ranged from one site with .55-12 sites in the .60-.69 range, and 20 sites with alpha of .70 or higher. The validity of the scale was indicated by low confounding with social desirability response set in all 33 cultural contexts, and by the results of construct validly analyses which controlled for physical maltreatment found that students who were victims of neglectful behavior as a child were more likely than other students to have physically assaulted a dating partner in the previous 12 months. CONCLUSIONS: Although the results are from a relatively privileged sample, they revealed high rates of neglectful behavior and are sufficiently promising to encourage use of the Adult Recall Short Form of the MNBS in a variety of cultural settings.  相似文献   

12.
OBJECTIVE: The number of youth in residential care programs who have been abused is high. The relationship between childhood abuse victimization and adult intimate partner violence (IPV) is well documented. This study compared the rates of IPV 16 years after individuals had participated in a long-term residential care program with individuals accepted to the program who did not participate. The IPV rates for these two groups were also compared to national normative data. METHOD: Information on adult functional outcomes was obtained from former residential care and comparison youth via a confidential survey that was administered either by telephone or by mail. Analysis was limited to respondents who were currently married or involved in a marriage-like relationship (n=131; 92% male). RESULTS: The IPV rates for the sample were 9.3% for those who stayed in the residential program less than 18 months and 6.5% for those who stayed more than 18 months, neither of which were significantly different from the national norm of 8.4%. The IPV rate for the comparison group was 26.1%, which was significantly higher than the national norm. Regardless of length of program stay, respondents who were maltreated in childhood had a 14.5% IPV rate, which was significantly lower than the estimated 36-42% rate projected for individuals with similar backgrounds. CONCLUSION: We conclude that time spent in a treatment-oriented residential care program was associated with lower adult IPV rates. Specifically, the skills taught in a long-term, treatment-based residential program (e.g., healthy interpersonal relationships, self-government) may have a long-term beneficial impact for adolescents at high risk of adult IPV.  相似文献   

13.
急性ST段抬高型心肌梗死继发心脏破裂的预测因素分析   总被引：2，自引：0，他引：2  
研究目的：心脏破裂是急性ST段抬高型心肌梗死最严重的并发症之一,病情凶险,死亡率高。通过明确心肌梗死后出现心脏破裂并发症的危险因素,早期识别心脏破裂高危人群,有利于在急性心肌梗死的早期采取干预措施以减少心脏破裂的发生。创新要点：既往缺乏对中国sT段抬高型心肌梗死继发心脏破裂的系统风险评估,本研究采用回顾性队列研究的方法,完善并健全中国多中心的急性心肌梗死数据库,样本总量达到9798例,为国内同类研究中样本量最多。既往的国外文献报道：女性、高龄、心梗后就诊时间延迟、前壁心肌梗死、溶栓治疗等是心肌梗死后心脏破裂的独立危险因素。本研究在中国人群验证以上危险因素的基础上首次提出就诊时血色素下降及白细胞计数的升高与随后发生的心脏破裂密切相关。新的心脏破裂预测因素的发现有利于对心脏破裂更精细化的危险分层,早期识别心脏破裂高危人群。研究方法：建立中国多中心心肌梗死数据库,比较发生心脏破裂与未发生心脏破裂患者临床特点的差异,筛选敏感特异的心脏破裂的独立预测因素。重要结论：中国人群急性ST段抬高型心肌梗死后心脏破裂的发生率是1．82％,独立预测因素主要包括：高龄、女性、就诊时静息心率增快、前壁心肌梗死、心功能不全、就诊时间延迟、肾功能不全、贫血与白细胞计数升高。本文第一次提出就诊时贫血状态及白细胞计数的升高时与心脏破裂的发生直接相关。  相似文献   

14.
碎裂QRS波对急性心肌梗死患者的短期预后评估(英文)简   总被引：2，自引：1，他引：1  
This study is aimed to investigate the clinical significance and the short-term prognostic value of frag- mented QRS （fQRS） for patients with acute myocardial infarction （AMI）. Three hundred patients with AMI were tested with retrospective analysis on the patients＇ clinical information, hospitalized treatment, fQRS onset time, location of lesions, and other relevant data, in order to assess the relationship between the presence of fQRS and its prognosis. The rates of malignant cardiac arrhythmia, left ventricular systolic dysfunction （LVSD）, and mortality in the positive fQRS group were 13.6%, 29.2%, and 23.7%, respectively, with all showing a p value 〈0.05. For the ST segment elevation myocardial infarction （STEMI） subgroup, all the rates showed significant differences with a p value 〈0.01, while for the non-STEMI （NSTEMI） subgroup showed no significant differences. In patients with a positive fQRS, there were no differences in malignant cardiac arrhythmia between patients with and without percutaneous coronary in- tervention （PCI） （p〉0.05）. As for the LVSD and mortality, the p values between patients with and without PCI were 0.031 and 0.000, respectively, suggesting statistical significance. The results imply that AMI patients with positive fQRS especially for the patients with STEMI had higher rates of malignant cardiac arrhythmia, LVSD, and mortality than the non-fQRS group. Patients of AMI with positive fQRS, who underwent early revascularization, could lower the incidence of the cardiovascular event. In addition, the presence of fQRS could be used as an indication of early in- tervention treatment for patients.  相似文献   

15.
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16.
Although college-aged women are at high risk for human papillomavirus (HPV) infection, many college women remain unvaccinated against HPV. Testing health behavior theory can assist sexuality educators in identifying behavioral antecedents to promote behavior change within an intervention. The purpose of this pilot study was to utilize social cognitive theory (SCT) to predict unvaccinated college women's intentions to receive the HPV vaccine within the next six months. A total of 197 unvaccinated college women ages 18–26 attending a large public southeastern university in the United States completed an online questionnaire to assess SCT constructs. Expectations, HPV knowledge, self-efficacy to get the HPV vaccine, situational perception, self-control to get the HPV vaccine, and self-efficacy in overcoming barriers to get the HPV vaccine were regressed on HPV vaccination intentions using the stepwise method. Self-control (p < 0.001, β = .292) and situational perception (p < 0.001, β = .332) were significant predictors of intentions to receive the HPV vaccine, explaining 23.5% of its variance. The results of this pilot study suggest that sexuality educators should aim to increase self-control and situational perception in order to increase HPV vaccination intentions among college women.  相似文献   

17.
One of the most important goals of child care research has been to determine whether or not nonparental care has adverse effects on child development. Answering this question involves making causal attributions about the origins of differences between groups of children who have experienced divergent nonparental care arrangements. Some of the problems researchers face when trying to demonstrate causal relationships are illustrated in this paper using data from the Göteborg Child Care Study, a comprehensive, prospective, longitudinal study comparing the developmental trajectories of children in exclusive home care, family daycare, and center daycare. It is argued that the discovery of significant differences between groups must initiate extensive efforts to validate and interpret the findings. Focusing on the specific characteristics of prospective longitudinal studies, the article shows what measures can be taken to avoid the misinterpretation of group differences that are actually attributable to pre-selection effects or confounding variables. By rigorously identifying such confounds, researchers can accumulate support for hypothesized causal relationships, but they cannot ‘prove’ them because unknown and unmeasured confounding variables may always have important effects.  相似文献   

18.
Retention is a frequently used strategy to support children who are struggling academically. However, the strategy is costly, and research findings with regard to positive outcomes are mixed. This study examined whether efficacious reading instruction might reduce rates of retention in first grade. We also evaluated the reading instruction the students received compared with children with similar reading and vocabulary skills who were not retained. Additionally, we examined the impact students' self‐regulation may have on grade retention. Findings reveal that it was significantly less likely for students to be retained at the end of first grade if their teacher was implementing more efficacious reading instruction. Moreover, there were substantial differences in the literacy instruction provided for children who were and were not retained. Finally, students in the efficacious reading condition who were retained exhibited significantly weaker self‐regulation skills than did their matched‐promoted peers. © 2012 Wiley Periodicals, Inc.  相似文献   

19.
Prior research on the labor market success of secondary vocational education has produced mixed results, with several studies finding wage gains only for individuals who work in training-related occupations. We contribute to this debate by focusing on a single occupation and organization and by comparing the careers of employees with and without occupation-related training in high school. We use longitudinal data on the careers of military recruits who completed high school Junior Reserve Officers’ Training Corps (JROTC), a military science program that has features of a vocational training and school-to-work program. We find that the occupation-specific training received via JROTC reduces early turnover and improves long-run job stability for those who choose military jobs, suggesting that an important effect of vocational training is to improve job match quality. We also find that promotion rates for vocational graduates are similar to their peers, suggesting that vocational education in general works by improving occupational sorting.  相似文献   

20.
This study investigated the performance of fit indexes in selecting a covariance structure for longitudinal data. Data were simulated to follow a compound symmetry, first-order autoregressive, first-order moving average, or random-coefficients covariance structure. We examined the ability of the likelihood ratio test (LRT), root mean square error of approximation (RMSEA), comparative fit index (CFI), and Tucker–Lewis Index (TLI) to reject misspecified models with varying degrees of misspecification. With a sample size of 20, RMSEA, CFI, and TLI are high in both Type I and Type II error rates, whereas LRT has a high Type II error rate. With a sample size of 100, these indexes generally have satisfactory performance, but CFI and TLI are affected by a confounding effect of their baseline model. Akaike's Information Criterion (AIC) and Bayesian Information Criterion (BIC) have high success rates in identifying the true model when sample size is 100. A comparison with the mixed model approach indicates that separately modeling the means and covariance structures in structural equation modeling dramatically improves the success rate of AIC and BIC.  相似文献   

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