The effect of cognitive and metacognitive strategies in academic achievement : A systematic review

The existence of different researches on the relationship between learning strategies and academic achievement indicates the positive and efficient influence of these strategies on the learning process. The present study was conducted using the systematic review method, and with the aim of investigating the effect of cognitive and metacognitive strategies on academic achievement. The population of the present study is available studies related to the effects of cognitive and metacognitive strategies on academic achievement in Iran and abroad. The period of investigation of internal articles was from 2004 to 2014, and the period of the investigation of articles published in other countries was from 2000 to 2014. The results of different research indicated that learning strategies such as cognitive and metacognitive strategies have had the most effects on academic achievement of school and university students in different courses. In general, it can be said that learning strategies, from each type (cognitive and metacognitive) in all studies (experimental, quasi-experimental, relational or correlational), in all learners (females and males) are very effective on the degree of their learning in different courses (experimental sciences, mathematics, and English Language).


Introduction
Human achievements in all fields of science have increased the significance of training learning strategies.Main point in training is that learners be taught to how to learn, how to memorize, and how to solve problems.Learners should know the most effective methods and strategies of learning.Researchers in their studies on students have reached these conclusions that a lot of learning problems and transferring them to students are due to the lack of learning skills in them.Learning strategies covers cognitive and metacognitive strategies and help learners for achieving their desired learning aims.Oxford defines learning strategies as a set of specific activities done by a learner for easier, more rapid, more joyful, more effective, and more transferable to new situations.The application of cognitive and metacognitive strategies is very important in facilitating learning, reminding, and memorizing processes.Cognitive and metacognitive strategies have the most powerful effects on learners' learning, and there is a positive and significant relationship between learning methods and academic achievement in universities and schools (Saied and Mehrabi, 2013;Yang, 2005).Flavell (2000) considers metacognition as a type of knowledge or cognitive knowledge whose subject is an aspect of cognitive measures and regulating them.In other words, he believes that this concept is metacognition because its main sense is re-identification of cognition.In fact, it can be said that if cognition refers to perception, processing, retaining, and transferring information, metacognition is an activity which covers the actions related to four mentioned elements and control them (Aghazadeh, 2011).Experimentally, it has been indicated that metacognition is related with studying, learning, critical thinking, solving problems and decision making and all these cases are necessary for educational successes (Scheifer and Dull, 2009).
During conducted research, different methods of learning and thinking or cognitive and metacognitive strategies indicated these strategies are learnable, i.e. teachers can independently and along with other courses, teach these learning strategies to their students and after teaching, students can voluntarily use these strategies and this measure has positive effects on learning and achievement (Saif, 1997).
Weinstein and Hume (1998) as cited in Saif (1997) have stated that teachers can help their students via teaching learning and studying skills (cognitive and metacognitive strategies) to be more successful learners and have more active roles in their academic fortunes.Flavell (1979) as cited in Saif (1997) investigated cognitive and metacognitive strategies and stated that learners apply all cognitive strategies to achieve their successes and use metacognitive strategies to have control over those successes and achievements.In addition, other studies indicated that there is a correlation between learning strategies and academic achievement (Karami, 2002).By training cognitive and metacognitive strategies, the increase in learners' learning and enhance their motivational beliefs towards training one can be assisted and their academic achievement can be provided (Beckman, 2002).Shouse, Chen and Hsieh (2007) emphasized the significance of preparing the educational system compatible with learning methods of students in schools.If educational material is compatible with students' cognitive styles, they will access better achievements and motivation.Another study indicated that using cognitive learning strategies can be effective on learning and academic achievement of learners (Meec, 1998).Training learning strategies can have positive effects on academic achievement (Fardi Yazdi, 2005).The issue of inability in appropriately acquiring and learning has extraordinarily attracted some of the educational research as well as experts and researchers of education in some school students and university students in recent years.Therefore, to access the mentioned objectives, better understanding of learnable issues is considered as one of the important educational objectives and activities.Therefore, the present study tries to investigate the effects of cognitive and metacognitive strategies on academic achievement in school and university students via a systematic review.

Methodology
In the present study, the method of systematic review of literature was used.The population of the present study is available studies related to the effects of cognitive and metacognitive strategies on academic achievement in Iran and abroad.The period of investigation of internal articles was from 2004 to 2014, and the period of the investigation of articles published in other countries was from 2000 to 2014.Accordingly, the population includes all articles published in research journals indexed in databases of SID, Irandoc, Magiran, and Noormags in Iran, as well as those journals published at the international level indexed in databases of Science Direct, Elsevier, Google Scholar such as American Psychologies, Pythagoras journal, journal of instructional pedagogies, International Education Journal, Journal of Behavioral Development.These journals used different correlational, causal-comparative, experimental and quasi-experimental research methods and designs to investigate the effects of cognitive and metacognitive learning strategies on the indicator of academic achievement.For primary investigations, firstly valid key words were determined based on literature review for using them in searching primary studies.Key words included learning strategy, cognitive and metacognitive strategy, self-regulated learning, academic achievement, learning strategies, academic success, etc.

Result
The objective of the present study was to investigate the effect of cognitive and metacognitive strategies on students' academic achievement in Iran and other countries using a systematic review of literature.Table 1 and 2 indicate the results obtained from different articles about the effect of cognitive and metacognitive strategies on students' academic achievement.In this table, author(s) and the year of publication, countries or cities in which each study has been conducted, research method and design, population, and at last final conclusions are reported.

Discussion and conclusion
In the present study, a systematic review of literature with the aim of determining the learning strategies (cognitive-metacognitive) on academic achievement.Learning strategies have a significance role in explaining the variance of academic achievement.The results of the present study indicated that the two cognitive and metacognitive strategies need each other, and in order that academic performance can be maximized, the two strategies should be applied.In addition, the results indicated that without having dominance over cognitive strategies, using metacognitive strategies has low effects (Mesrabadi, Erfani & Adab, 2014).The results of the different studies indicate that both cognitive and metacognitive strategies are highly effective on academic success and achievement.The results of the research conducted by Maroofi (2014) and Karami (2013) indicated that cognitive and metacognitive strategies are the most effects on academic achievement in students for the courses of experimental sciences, and students who use these strategies have been mostly much more successful than those who do not use them.In addition, the results of the research of Salehi (2013) indicated that nursing students use strategies of repetition and rehearsal and semantic expansion more than strategies of organizing and critical thinking.It can be said that because these methods cause the activation of readers and cause them to mentally process information actively, learning enhances.Training cognitive strategies for example mental rehearsal firstly help students to select the points which are important and worthy to be reminded.Secondly, it is highly probable that the important points find their ways into memory and consequently be processed and studied (Sifert, 1991).The findings of the research done by Magogwe (2013), Zhang (2013) and Eluemuno (2013) indicate that cognitive and metacognitive strategies are significant for training students' English and academic achievement in this course.Metacognitive strategies are very constructive for attaining success in learning and academic achievement and this issue is due to metacognitive strategies are considered in learning process as one of the important cognitive action, and their roles are to increase students' abilities in realizing their potentials.Henk and Graaff (2004) believe that in metacognitive strategies, learners are trained with self-regulation, understanding learning subjects, and the sense of knowing.The self-regulating learner identifies his aims himself and when he is deviated from accessing these aims, manages learning actively.Research done by Peng (2012) and Lee (2008) indicated that cognitive and self-regulative strategies are effective on students' satisfaction with educational system and their academic performance.Regarding the results of different studies, it can be observed that cognitive and metacognitive strategies have high positive effects on students' academic achievement.It is recommended that cognitive and metacognitive strategies concurrently be considered as the priorities of curricula in schools and educational institutes.