Investigating the effects of distance education on academic achievement of students in a meta-analysis

The purpose of this study is to combine quantitative results from research on the effects of distance education and its comparison with the traditional method on academic achievement of students by the application of meta-analysis. The statistical population of the study is all researches conducted in Iran on the impact of distance education and its comparison with the traditional method on students' academic achievement. In accordance with the criteria of the present study، 51 studies from total of 138 studies were conducted by using statistical analysis CMA V2. By using Cohen's d the average of the effects of distance learning method and traditional method were 0.98 and 0.47, respectively  and then by using T-test was compared the effect of these two methods.By accepting the assumption of inequality of variances, the results indicates that between the effect of distance education and the traditional and traditional method there is a significant difference with a significance level of 0.02 which is less than 0.05 (sig = 0.001> 0.05) .In other words, distance learning‌ students have more academic achievement than regular students.