meta-analysis

Becoming one of six official United Nations languages, English proficiency has become a prominent requirement for students and professionals entering international education and/ or careers, as assessed through standardized English proficiency tests. English learners conducted varied procedures to pursue the minimum test score criteria, including joining an English test preparation program. This study investigates the effect of English test preparation as an intervention on EFL learners' English language proficiency performance by reviewing the effect sizes found by previous studies using meta-analysis of pre-post contrasts. A total of 20 selected studies, according to the criteria determined by researchers between 2018-2021 and conducted in various countries, were collected from Google Scholar sources and included in the research. English language proficiency performance, as indicated by their test scores, is independent of the language skills tested with a p-value of less than 0.05 (p-value = 0.00) and an average weighted effect (M) that appears to be 0.859. This research implies that adequate test preparation is essential for English language learners who wish to achieve the desired level of proficiency. Apart from the ability to write, speak, and read, the psychological aspects of students are also important to prepare before they take the intended test

With the aim of comprehensively investigating the most important consequences of website quality in e-commerce, this research has collected and analyzed data about the relationship between website quality and customer trust, satisfaction, and loyalty. In this regard, various studies were collected and coded. After that, the eligible studies to enter the meta-analysis based on the determined criteria were identified to be 49, 68, and 29 studies for the relationship between website quality and trust, satisfaction, and loyalty, respectively. The findings of data analysis using CMA2 software showed that website quality has the strongest relationship with satisfaction with an effect size of 0.591 and the weakest relationship with loyalty with an effect size of 0.516. The effect size of trust was also positive and equal to 0.555. In addition, the findings from the analysis of moderator variables also showed that an increase in the year of publication led to a decrease in the effect size of website quality-trust studies but an increase in the effect size of website quality-satisfaction and website quality-loyalty studies. Additionally, with an increase in the sample size, the effect sizes of website quality-trust studies increased, but the effect sizes of website quality-satisfaction and website quality-loyalty decreased.

In this research, we carried out a meta-analysis of the effects of teacher scaffolding on EFL learners’ reading proficiency in which 28 experimental and quasi-experimental studies published from 2008 to 2022 and 39 effect sizes were reviewed and synthesized. Three questions guide this analysis: What is the overall effect of teacher scaffolding on EFL learners’ reading proficiency? To what extent moderator variables such as learners’ educational levels and proficiency levels modify the effect of the teacher scaffolding? What is the magnitude of publication bias in this analysis? The overall effect size was found to be 0.89, which represents a large effect size based on Cohen, Manion and Morrison’ (2007) scale. The effect sizes of moderator variables were calculated and it was reported that the scaffolding has the most effect in elementary learners and elementary school level. The symmetrical funnel plot together with the fail-safe N test indicates that publication bias does not have any significant effect on the effect size reported in this study. The findings of this meta-analysis have implications for EFL teachers, researchers, policy makers and curriculum developers.

One of the important challenges of organizational behavior is bullying in the workplace. The aim of the present study is to describe, analyze, and combine the analyses presented in the field of variables related to bullying in the workplace, and the meta-analysis method was used. The statistical population of this study included all scientific research articles and thesis available on the IranDoc website in Iran from 2011 to 2014. Among the studies conducted, 16 studies were selected for review based on the inclusion criteria. The data from these 16 studies were statistically analyzed based on the Pearson r correlation coefficient and the t-statistic for the Hedges' g fixed and random effects model. All statistical analyses were performed using CMA2 software. The findings showed that the average overall and combined effect size for the fixed effects model was 0.07 g=0.05, which was significant (P<0.05) and for the random effects model was 0.10 g=0.05, which was not significant (P<0.05). Therefore, the average effect size of the factors cannot be interpreted. Among the 48 factors identified, the discriminant effect size of 45 factors was significant. The factors that have the greatest impact on workplace bullying (P<0.05) include authoritative leadership (g=-1.28), demand balance (g=-1.01), fairness (g=1.01), excessive self-interest (g=1.44), contextual factors (g=1.56), jealousy (g=1.35), moral climate (g=-1.96), and moral leadership (g=-1.13).