A meta-analytic and thematic study concerning the effect of inquiry based instruction on learners' achievement

This research aims at investigating the effect of Inquiry-Based instruction (IBI) on learners' academic achievement through meta-analytic and thematic approaches. In the meta-analytic study, 27 studies, which were implemented between 2000 and 2016 years, were examined. CMA and MetaWin statistical programs were used to calculate the effect sizes of these studies. The effect size (0.688) of the study indicates that the use of IBI has a positive effect on learners' achievement. To support findings of the meta-analytic study, a thematic study including 36 studies was applied. As a result of the analysis of the latter study, five themes, namely affective, cognitive and social domain themes, learning environment and negative aspects were generated. The former four themes demonstrated that IBI positively affects learners' achievement except the negative aspects theme. The negative theme stresses out that the effectiveness of IBI depends on how well the IBI activities are planned beforehand. If they are planned in detail, learners can know what to do in the activities. So, IBI can be used systematically in learning as an alternative method which can meet students' needs in technological era.


Introduction
Knowledge plays a crucial role in promoting countries to develop in technological, educational, socio-economic aspects. This is notable with the changes in technology and in the structure of employment which require citizens to get high level cognitive skills including the perception, interpretation, analyzing and transmission of confused knowledge (OECD, 2012). As a matter of fact, thinking and productive individuals can train these citizens who can meet their countries' needs. In this way, countries can sustain their entities in developed civilizations. Training thinking and productive individuals is possible with quality education systems. There are different approaches for quality issue in education. In other words, there is not a single definition for the quality issue in education and a number of items with regard to this issue can be compiled. To illustrate, learners' being very active and creative, acquiring knowledge through their experiences and reconstructing the knowledge by associating with their previous one (Osborn, 2013), teachers' guidance how to construct learners' knowledge, their encouragement to generate new ideas, their preparation for learning environment where different teaching methods and techniques are used (Eryaman & Bruce 2015;Ranjan & Rahman, 2014;Shaikh & Khoja, 2012), learners' cognitive, creative and affective development with their citizenship attitudes and values (Yıldırım, 2009) can determine the quality issue in education.
It is indicated in a number of studies that the methods used in the education systems are inadequate for the learners in the 21st century who encounter different needs (Alberta Education, When learners' different needs, interests in technological era are concerned, it is seen that teacher centred approach is not an effective method to enable them to acquire higher-level cognitive skills to find jobs in today's employment system. These skills require them to do research, inquiry and solve problems. They should reconstruct their acquired knowledge and come up with ideas to solve problems. As indicated by Serafin, Dostal and Havelka (2015) that the current social needs require an individual with the creative thinking to find the problems and solve them effectively. In this regard, Inquiry-Based Instruction (IBI) method can play a crucial role in ensuring them to develop their cognitive skills. This method is based on John Dewey's philosophy of education and it involves skills such as solving problem in learning process, conducting research and generating solutions (Erdem, 2006). As indicated by Dostal (2015) that "the inquiry-based instruction is an activity of a teacher and a pupil that is focused on the development of the knowledge, skills, and attitudes based on the active and relatively individual cognition of the reality by the pupil who learns on his/her own how to explore and explores." (p.79). This method starts with learners' curiosity on a particular issue with a willingness to do research. In this process, they collect, compile and analyze data with regard to the issue and then come to a conclusion or decision on this issue. In this method, learner is actively involved in exploring and constructing knowledge. That is, student and process of learning are in the core of IBI instruction (Aulls, Magon & Shore, 2015).
This study is concerned with revealing to what extent IBI has an impact on learners' grades in their courses. That is, it focuses on the relationship between the effect of the use of IBI in learning and learners' academic achievement. As a result of the literature review, it was found out that any study involving both meta-analytic and thematic approach has not been encountered to enlighten this relationship. So, the findings of the current study are hypothesized to make a valuable contribution to researchers, teachers, pre-service teachers, academic members responsible for training teachers, learners and designers for curriculum in education. i.
In the current study, questions that follow are answered: ii.
What is the effect size of the use of IBI in learning on learners' academic achievement? iii.
What are the participants' perceptions with regard to the use of IBI in learning?
and qualitative techniques were applied to reveal more general and comprehensive findings to the related literature.

Data Collection and Analysis
In the quantitative part, meta-analytic method, a statistical technique to incorporate the findings of the separate studies with respect to similar issues (Crombie & Davies, 2009) by Miles and Huberman (1994) was conducted to ensure the reliability outcome of the study. As a result of the calculation, it was found out to be 100%.
Thematic analysis was added in the study to support and complement the meta-analytic aspect of the study. As a result of the document review of the related literature, 36 studies with regard to IBI were included. These studies were coded into computer as: (178571-53). The former number (178571) in the parenthesis refers to the number of the thesis in the Higher Education Council of the Republic of Turkey and the latter number (53) indicates the page of the code in the related thesis. In the other codes Thesis (T) and number are used. Then, they were analyzed thematically. The content analysis was used to analyze the obtained data in the studies through Maxqda-11 program. In the analysis process, the expressions were coded and categorized under different themes.

Findings and Comments
In this section, the quantitative and qualitative findings related to the effect of IBI on learners' academic achievement were presented. In this way, all the findings were integrated with each other and complementary or different points were indicated.

The Quantitative Analysis Results of the Studies With Regard to IBI
Based on the selection criteria, 27 studies were included in the meta-analytic review. In Table   1, the frequency values for categorical independent variables of the studies, namely subject area and grade level, on the effect of IBI on learners' academic achievement were presented. When subject area variable is examined in Table 1, it is seen that most studies were implemented with the science course (n=10), and then science and technology (n=7), chemistry (n=2), physics (n=2), and mathematics (n=2) respectively. If the grade level variable is considered, it will be noticed that most of the studies were carried out with the students in lower-secondary school (n=14), upper-secondary school (n=5), elementary school (n=4), and then university (n=4). It is recognized that the studies with regard to IBI focus on sciences courses with the students in lower-secondary schools. It can be inferred that students are more likely to inquiry, do research, and explore in science courses.  In

Figure 1: Normal quantile plot
The chart of the Normal Quantile Plot was presented in Figure 1 to see if the effect sizes of the studies were suitable for the normal distribution using the MetaWin program. Through the chart control, the reliability of the meta-analysis is tested. In Figure 1, the distribution of effect size indicated a normal process as any large deviations in the effect sizes didn't emerge. Based on the normal distribution of effect sizes, it can be stated that combining the studies in the meta-analytic process is statistically relevant. Moreover, in meta-analysis publication bias can be encountered and Rosenthal (1979)  In the context with the qualitative research, the participants' perceptions for the use of IBI in learning were studied to reveal what they think about the role of IBI in education. So, their perceptions were examined in different dimensions. As a consequence of the content analysis of the 36 studies in the qualitative research, five themes, namely affective domain, cognitive, social domain, learning environment and negative aspects were obtained. This section dwelled on these five themes and related codes. These codes are based on the participants' self-stated opinions in the studies included in the thematic studies. Furthermore, through the participants' quotations, the themes and codes were supported and enriched.
The participants' perceptions for the affective domain theme on with regard to the use of IBI in the learning process are presented in Figure 2. In terms of this theme, several codes such as different from previous expressions, appealing to a variety of senses, perceiving previous course boring, increasing students' self-confidence and perceiving the method interesting and useful were generated.
These codes were formed considering the participants' expressions in the studies.  show similar points in the study by Dostal (2015) indicating that the tasks concerning inquiry-based approach are frequently time-consuming. Therefore, the guided activities developed based on this approach play a significant effect on the students' academic achievement (Duran, 2014). Guided activities and well planning beforehand are thought to reduce the negative aspects in this approach.
As a result of the analysis of both the quantitative and the qualitative findings, IBI can be used systematically to increase learners' awareness, interests, attitudes and achievements in their courses.
Taking into account how well they are competent to use technology, IBI activities supported with technology can be developed to increase their curiosity, thereby enabling them to acquire highlyordered thinking skills. These activities should be enhanced with guided and well planned directions to decrease the negative sides of IBI in learning process. Academic members, researchers, decision makers, teachers can benefit from the findings of the current study to develop the curriculum for especially digital native learners.