Institute of Educational

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The purpose of this research was to conduct a meta-analysis of the studies on the effect of blended learning on academic performance in Iran. The meta-analysis was based on the estimated effect size of blended learning on academic performance. 211 studies were identified in the period 2010-2017, of which 20 research documents were selected using non-probability (purposive) sampling. Initial data analysis was done in SPSS using the PRISMA checklist, and Cohen’s model was used to interpret the results. The results showed that there is a significant positive relationship between blended learning and academic performance. The estimated effect size for this relationship was 0.684, which is higher than the medium level in Cohen’s model (0.5). This indicates the real effects of the blended learning approach on academic performance. Overall, the results showed that the blended learning approach, with proper needs assessment, design, implementation, evaluation, and feedback, can be a logical and flexible strategy for improving academic performance.
 

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The aim of this study was to investigate the efficacy of educational interventions on students' critical thinking and Comparison of this effect in elementary, junior and high school students by using meta-analysis method based on the Hunter and Schmidt approach. Fifteen studies which were accepted methodologically and conducted within the last 10 years in Iran were included in the meta-analysis. The checklist of meta-analysis with 1222 participants were used. The results indicated that the effect size of educational interventions on students' critical thinking was 0/43. The effect size in elementary, junior and high school students was 0/32, 0/45 and 0/61. Also, the results of modulatory analysis showed the efficacy of moderating variables in these interventions. Based on the results of the present meta-analysis, the effect of educational interventions on students' critical thinking according to Cohen's table was above average. This effect rate was evaluated moderate in elementary students, above average in junior high school students and high in secondary school students. The effect of moderating variables in elementary school was higher than the first and second secondary school.

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The main objective of this study was to synthesize the findings of different studies and gain a general understanding of the effectiveness of psychological interventions on academic procrastination. The study population consisted of available full-text Articles, dissertations, and research projects published from 2011 to 2021 in quarterly publications and scientific research journals. Based on inclusion and exclusion criteria and sensitivity analysis, 136 effect sizes from 83 initial studies were analyzed using CMA2 software. The results revealed a statistically significant combined effect size for both fixed and random effect models, and the combined effect size for the random-effects model based on Cohen's criterion was large (ES = 1.47). In reducing academic procrastination, the findings indicated a high effect of self-regulation intervention compared to other interventions. Also, examining the variables of gender and educational level of the learners as moderating variables in the research showed that the gender of the subjects had no effect on the effectiveness of the psychological interventions, and the efficacy of interventions had a significant difference in the educational levels. This research has implications for therapists and counselors in line with the effectiveness of psychological interventions, especially the training of self-regulation components, to improve students' academic procrastination by providing programs.