Bias Corrections for Standardized Effect Size Estimates Used With Single-Subject Experimental Designs

A multilevel meta-analysis can combine the results of several single-subject experimental design studies. However, the estimated effects are biased if the effect sizes are standardized and the number of measurement occasions is small. In this study, the authors investigated 4 approaches to correct for this bias. First, the standardized effect sizes are adjusted using Hedges’ small sample bias correction. Next, the within-subject standard deviation is estimated by a 2-level model per study or by using a regression model with the subjects identified using dummy predictor variables. The effect sizes are corrected using an iterative raw data parametric bootstrap procedure. The results indicate that the first and last approach succeed in reducing the bias of the fixed effects estimates. Given the difference in complexity, we recommend the first approach.     

复合式训练影响青少年下肢爆发力的meta分析

目的：运用元分析的方法检验复合式训练对青少年下肢爆发力影响的干预效果,检验并提出最优的运动干预方案。方法：运用STATA 15.1和Review Manager 5.3对纳入的10篇文献和301名被试者通过设置抗阻类型、抗阻强度、间歇时间、训练频率和训练周期等5个调节变量进行亚组分析,采用固定效应模型进行整体效应、异质性、发表偏倚性检验。结果：（1）复合式训练对跳跃类运动表现的影响效应量d0.36,对短跑类运动表现的影响效应量d-0.51,两者达到中等效应且具有统计学意义;（2）本研究纳入的10篇文献异质性较低,间歇时间、训练频率和训练周期的对跳跃类和短跑类运动表现影响的效应量有一定差别。结论：（1）复合式训练能够显著提升青少年跳跃类和短跑类运动表现;（2）抗阻训练选择等张收缩、强度70%1RM以下、小于3分钟的间歇时间、在4~8周内选择每周1-2次的复合式训练能够对青少年运动表现有较好的提升;（3）围绕青少年人群开展的复合式训练较为缺乏,后续研究应加强理论与实践研究。     

Application of network meta-analysis in the field of physical activity and health promotion

Continued advancement in the field of physical activity and health promotion relies heavily on the synthesis of rigorous scientific evidence. As such, systematic reviews and meta-analyses of randomized controlled trials have led to a better understanding of which intervention strategies are superior (i.e., produce the greatest effects) in physical activity-based health behavior change interventions. Indeed, standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures that produce reliable estimates of the homogeneity, magnitude, and potential biases in the observed effects. However, pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison or control condition. In order to maximize the impact of physical activity interventions on health-related outcomes, it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention strategies. The development of network meta-analysis (NMA)—most commonly used in medical-based clinical trials—has allowed for the quantification of indirect comparisons, even in the absence of direct, head-to-head trials. Thus, it stands to reason that NMA can be applied in physical activity and health promotion research to identify the best intervention strategies. Given that this analysis technique is novel and largely unexplored in the field of physical activity and health promotion, care must be taken in its application to ensure reliable estimates and discernment of the effect sizes among interventions. Therefore, the purpose of this review is to comment on the potential application and importance of NMA in the field of physical activity and health promotion, describe how to properly and effectively apply this technique, and suggest important considerations for its appropriate application in this field. In this paper, overviews of the foundations of NMA and commonly used approaches for conducting NMA are provided, followed by assumptions related to NMA, opportunities and challenges in NMA, and a step-by-step example of developing and conducting an NMA.     

Sport-based physical activity intervention on body weight in children and adolescents: a meta-analysis

Controversial results reported in past research pertaining to the effectiveness of sport-based physical activity interventions on weight loss. The purpose of this study was to assess the impact of sport-based physical activity intervention on body weight in children and adolescents using a meta-analysis. Academic Search Complete, Education Source, ERIC, Medline, ProQuest, PsycINFO and SportDiscus databases were searched from January 2000 to April 2015. Eighteen studies met following inclusion criteria: sport-based intervention studies; subjects aged 6–18 years; reported body weight; published in peer-reviewed journals written in English. The mean intervention duration was 17.72 weeks. The overall effect size (ES) was 0.52 (Cohen’s d (ES) = 0.52, 95% CI = 0.08, 0.95, P = 0.021), using a random effects model. Moderator analyses results showed that the Q statistic for the sport type (individual sport or team sport, Qbetween (Q_b) = 14.52, df = 1, P = 0.001) and diet control (Qbetween (Q_b) = 8.85, df = 1, P = 0.001), explained the heterogeneity of ESs. Our study showed that there was a moderate overall effect of sport-based physical activity intervention on body weight reduction. The team sport type (ES = 1.05, 95% CI = 0.44, 1.66) and diet control group (ES = 0.84, 95% CI = 0.26, 1.41) appeared to be more effective in reducing body weight.     

体育锻炼与文化成绩的相关联分析研究 ——以一分钟仰卧起坐为例

体育活动对青少年智育发展有积极的作用,但对学生的文化成绩影响还有待深入研究.研究分层抽样调查了广东省2499名小学生,通过测试体育运动项目一分钟仰卧起坐和文化成绩(语文、数学和英语),应用线性回归模型以校正性别,年龄,身高,体重,体重指数等因素的影响,在不同学校,多个年级的多个水平上,衡量体育运动能力对文化成绩的效应,并用meta分析和pooled分析综合评估其效应值的大小,最后采用偏相关系数进一步描述了一分钟仰卧起坐成绩与小学生文化成绩之间的关联.二者相关关系是客观存在的,这也暗示了鼓励和促进小学生积极参加体育锻练对于提高学习成绩的意义.     

知觉预测领域专家-新手研究范式的元分析

摘要：研究目的：探讨知觉预测领域专家-新手研究范式的实效性和知觉预测领域专家-新手研究范式是否受体育项目、刺激材料、遮蔽方式的影响。研究方法：元分析方法。研究结果：知觉预测领域专家-新手研究范式中反应时、准确率、注视次数为大效应,注视时间、注视频率为中效应,且大、中效应稳定的。反应时、准确率、注视次数、注视时间、注视频率的效果量在不同体育项目、不同刺激材料、不同遮蔽方式上存在差异。结论：知觉预测领域专家-新手研究范式具有很好的实效性,其大、中效应的存在与专家认知优势有密切的关系;体育项目、刺激材料、遮蔽方式是知觉预测领域专家-新手研究范式的调节变量。     

双元、悖论式领导对绩效的影响

组织发展面临的张力越来越普遍,双元领导、悖论式领导日益引起理论界关注。然而双元领导、悖论式领导与创新绩效、任务绩效之间的关系如何?两种领导行为对两种绩效的影响是否存在差异?两种领导行为对创新绩效的影响是否会受到领导者层级的影响?上述问题亟待解答。对50项研究共13 232个样本进行元分析,分析结果发现：双元领导、悖论式领导分别对创新绩效、任务绩效有正向影响;双元领导、悖论式领导对创新绩效、任务绩效的影响不存在显著差异;双元领导、悖论式领导对创新绩效的影响不受领导者层级的调节作用。研究证实了两种相近领导行为影响不存在差异,为未来研究中的变量选择提供了依据,对实践中不同层级领导力开发提供了启示。     

How to unring the bell: A meta-analytic approach to correction of misinformation

The study reports on a meta-analysis of attempts to correct misinformation (k?=?65). Results indicate that corrective messages have a moderate influence on belief in misinformation (r?=?.35); however, it is more difficult to correct for misinformation in the context of politics (r?=?.15) and marketing (r?=?.18) than health (r?=?.27). Correction of real-world misinformation is more challenging (r?=?.14), as opposed to constructed misinformation (r?=?.48). Rebuttals (r?=?.38) are more effective than forewarnings (r?=?.16), and appeals to coherence (r?=?.55) outperform fact-checking (r?=?.25), and appeals to credibility (r?=?.14).     

新课程标准下中学体育教育模式的元分析

探索新课程标准下具体的教学方法与程序是体育课程改革中的关键问题。运用元分析方法,对有关中学体育教学模式的实验研究成果进行定量分析,结果发现体能类项目效果量中等,心理指标的效果量总体较大,男女生效果量总体差异不明显。研究还发现,有关体育教学模式的实验研究数量较少,实验研究成果多集中在经济发达地区,现有的研究理论层次不高,研究不够深入,重复研究较多,且存在重复利用一次研究数据的情况。全面实施新的体育与健康课程标准仍有诸多现实问题需要解决。     

体育锻炼与大学生心理健康的关系:一项元分析研究

使用元分析方法对我国大学生体育锻炼与心理健康关系的研究共15项进行定量化综述研究.结果表明,参加体育锻炼的大学生群体与不参加体育锻炼的大学生群体相比较,前者的心理健康综合指标得分值优于后者0.29个标准差.体育锻炼有利于促进大学生的心理健康.