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The problem of this study is how to make a link between four studies, which reflect how they integrated to make one pound study, or how they are aligned together in order to explain and interept the chanalenges facing the sudan economy. So study is aggregation to four studies by using meta-analysis method which is suitable for intergrating studies with the aim of elaborating main stream focusing in how the different studies under consideration reaching same results with different methods. Hence here the study seeks for increasing the power of testing the main question of the study which is the challenge that faced the Sudan economy particularly the structural distortion of economic variables. The study gathered the results of the four mentioned studies which are almost concerned with the exchange rate. The results confirmed the structural problem which faced the Sudan economy, while meta-analysis results assured and empowered the hypothesis of the study in terms of significant effect size. Moreover, the results consolidated the similarity of the studies in manipulating the problem of this study. In addition to that the heterogeneity stems from differences in the effect size of each study rather than differences in the sample sizes of the studies. Finally the study of exchange rate volatility has greater effect size, next to the study of estimating the error correction of exchange rate model while the studies of appropriate estimator of exchange rate and profitability of commercial banks have slight and insignificant effect size. Finally the different results assure the convenientability of meta analysis in reflecting the chellenges that faced the Sudanese economy and their ramifications, then accordingly the suggested remedies which may help in tackling the matter.