Improving cognitive and physical function through 12-weeks of resistance training in older adults: Randomized controlled trial

ABSTRACT

We performed a randomized, controlled trial to analyse the effects of resistance training (RT) on cognitive and physical function among older adults. Fifty participants (mean age 67 years, ~60% woman) were randomly assigned to an RT program or a control group. Participants allocated to RT performed three sets of 10-15RM in nine exercises, three times per week, for 12-weeks. Control group did not perform any exercise. Variables included cognitive (global and executive function) and physical function (gait, mobility and strength) outcomes. At completion of the intervention, RT was shown to have significantly mitigated the drop in selective attention and conflict resolution performance (Stroop test: -494.6; 95%CI: -883.1; ?106.1) and promoted a significant improvement in working memory (digit span forward: -0.6; 95%CI: ?1.0; ?0.1 and forward minus backward: -0.9; 95% CI: ?1.6; ?0.2) and verbal fluency (animal naming: +1.4, 95%CI 0.3, 2.5). No significant between-group differences were observed for other cognitive outcomes. Regarding physical function, at completion of the intervention, the RT group demonstrated improved fast-pace gait performance (?0.3; 95% CI: ?0.6; ?0.0) and 1-RM (+21.4 kg; 95%CI: 16.6; 26.2). No significant between-group differences were observed for other mobility-related outcomes. In conclusion, RT improves cognitive and physical function of older adults.     

Bounding,An Accessible Method for Estimating Principal Causal Effects,Examined and Explained

Estimating treatment effects for subgroups defined by posttreatment behavior (i.e., estimating causal effects in a principal stratification framework) can be technically challenging and heavily reliant on strong assumptions. We investigate an alternative path: using bounds to identify ranges of possible effects that are consistent with the data. This simple approach relies on fewer assumptions and yet can result in policy-relevant findings. As we show, even moderately predictive covariates can be used to substantially tighten bounds in a straightforward manner. Via simulation, we demonstrate which types of covariates are maximally beneficial. We conclude with an analysis of a multisite experimental study of Early College High Schools. When examining the program's impact on students completing the ninth grade “on-track” for college, we find little impact for ECHS students who would otherwise attend a high-quality high school, but substantial effects for those who would not. This suggests a potential benefit in expanding these programs in areas primarily served by lower quality schools.     

Does Fidelity of Implementation Account for Changes in Teacher–Child Interactions in a Randomized Controlled Trial of Banking Time?

This study examined fidelity of implementation in a randomized trial of Banking Time, a classroom-based intervention intended to improve children's behavior, specifically for those at risk for developing externalizing behavior problems, through improving the quality of teacher–child interactions. The study sample comes from a randomized controlled trial that took place over three years and included 183 teachers and 470 preschool children recruited across three sites. Results exploring fidelity of implementation indicated that Banking Time practices were present across treatment and nontreatment groups. In addition, the presence of more Positive Banking Time Practices accounted for improvements in teacher–child interactions while Restricted Banking Time Practices showed inconsistent patterns, relating both to positive and negative teacher–child interactions. Further, random assignment to Banking Time resulted in the presence of more Positive Banking Time Practices and fewer Restricted Banking Time Practices, which accounted for the improved teacher–child interactions. Thus, findings point to the critical need to better account for intervention fidelity across conditions in randomized trials, allowing for better understanding of the mechanism through which interventions lead to intended outcomes.     

Acquiring Clinical Knowledge from an Online Video Platform: A Randomized Controlled Experiment on the Relevance of Integrating Anatomical Information and Clinical Practice

Basic subjects in medical education, such as anatomy, are often taught through teaching formats that do not always sufficiently demonstrate the relevance of this basic information for clinical practice. Accordingly, it is a recent trend in anatomy education to link anatomical information more explicitly to clinical practice. This article presents an online video platform (Tuebingen’s Sectio Chirurgica [TSC]) as one means of explicitly integrating preclinical anatomical knowledge and clinical application. The purpose of the study presented here was to examine the effects of videos through which medical students were educated about Anterior Cruciate Ligament reconstruction. A TSC video about this surgical procedure was compared to a video with a traditional lecture providing the identical information. Participants (n = 114) perceived the TSC video to be superior in comprehensibility of the presentation (P = 0.003) and conceivability of the surgical procedure (P = 0.027), and to be more entertaining (P < 0.001). Moreover, participants in the TSC condition acquired more clinical knowledge than in the lecture condition (P = 0.043) but did not differ in their acquisition of anatomical knowledge. Mediation analyses indicated that the effect on the acquisition of clinical knowledge was mediated by comprehensibility, conceivability, and entertainment. These findings are discussed regarding their implications for medical education in terms of contributing to the general trend of linking preclinical anatomical knowledge to clinical application. A discussion about the limitations of the study and suggestions for future research are also provided.     

基于Zelen设计的网络用户信息检索行为实验方案与评估

在介绍并评价当前主要检索行为实验方法的基础上，引入美国Marvin Zelen 教授的Zelen设计，综合已有检索行为实验方法的优缺点给出应用于网络用户信息检索行 为实验的改进Zelen实验设计方案。最后，文章从实验对无关变量控制的规范化评价、实 验方法的规范化评价、实验内在效度评价和实验外在效度评价4个方面对这一实验方案进 行了评估。     

Impact of the National Writing Project's College-Ready Writers Program in High-Need Rural Districts

By 2013, all 50 states and the District of Columbia had adopted college- and career-ready standards in English language arts and mathematics, placing a greater emphasis on argument writing to prepare students for life after high school. Solving the specific problem of how to help teachers teach to new standards for argument writing as well as the broader problem of improving teaching and learning requires continued efforts to understand how to support teachers in making substantial changes in instruction. This paper reports on a district-randomized controlled trial of the National Writing Project's College-Ready Writers Program (CRWP), implemented in high-need rural districts in 10 states, testing one instance of professional development paired with supporting curricular resources and a formative assessment tool designed to shift instruction to align with the new college- and career-ready standards in English language arts classes in Grades 7–10. Researchers randomly assigned 44 rural districts either to receive two years of CRWP or to be in a business-as-usual control group and found positive impacts on teacher practice and student source-based argument writing.     

A prospective,randomized crossover study comparing direct inspection by light microscopy versus projected images for teaching of hematopathology to medical students

Instruction in hematopathology at Mayo Medical School has evolved from instructor‐guided direct inspection under the light microscope (laboratory method), to photomicrographs of glass slides with classroom projection (projection method). These methods have not been compared directly to date. Forty‐one second‐year medical students participated in this pilot study, a prospective, randomized, crossover study measuring educational performance during a hematology pathophysiology course. The students were randomized to one of two groups. All students received the same didactic lectures in the classroom and subsequent case‐based review of peripheral blood smears using either laboratory or projection methods, on day one with a crossover to the other method on day two. Pre‐ and post‐test examinations centered on morphology recognition measured educational performance on each day, followed by a questionnaire identifying the student's favored method. There was no significant difference in the pre‐test and post‐test scores between the two teaching methods (rank‐sum P = 0.43). Students overwhelmingly preferred the projection method and perceived it as superior (76%), although post‐test scores were not significantly different. Student's recommended method was split with 50% favoring the projection method, 43% favoring a combined approach, and 23% noting logistical challenges to the laboratory. In this study, the laboratory and projection method were equivalent in terms of educational performance for hematopathology among medicals students. A classroom‐based approach such as the projection method is favored, given the large class sizes in undergraduate medical education, as well as the ergonomic challenges and additional resources required for large group instruction in a laboratory setting. Anat Sci Educ 7: 130–134. © 2013 American Association of Anatomists.     

基于R-R技术的腐败程度统计推断

本文借助于敏感性问题调查技术--随机化问题回答技术(R-R技术)对局部部门(领域)的腐败程度进行统计推断,客观评估部门(领域)腐败实际状况,对构建腐败治理的测评体系将会起到一定的作用.     

Effects of problem-based discussion on studying a subsequent text: A randomized trial among first year medical students

The Purpose of this study was to examine effectsof group discussion of a medical problem on the comprehension of a subsequentproblem-relevant text by first year medical students.Forty-eight first-year medical students were randomly assigned toone of two conditions: The experimental group discussed a problem of blood pressureregulation, where the control group discussed a problem of vision. Subsequently, allstudents studied a text on the physiology of blood pressure regulation. Finally, a freerecall test was administered. Numbers of propositions accurately recalled were analyzed usinganalysis of variance (ANOVA). Students who discussed the blood pressure regulationproblem recalled 25% more from the text than those who discussed the control problem.This difference was statistically significant. The present study represented thefirst truly randomized trial in the ecologically valid context of a medical curriculum. Itdemonstrated the positive effects of problem-based tutorial group discussion on thecomprehension of text. It confirmed earlier findings from laboratory studies thatproblem-based learning, in addition to positive emotional and motivational long-term effectswell-documented in the literature, also has positive effects on learning.