Research Variables

Conducting Educational Research
Step 2: Identify Key Variables and Research Design

Once you have brainstormed project topics, narrowed down the list, and reviewed the research related to that narrowed list, select a topic that seems most appealing to you. However, this project topic is not set in stone yet. After you begin working through the project, you may realize that the topic needs to be revised, or even entirely changed to a different topic. The next step is to identify the key variables and the research design.

Key Variables

All research projects are based around variables. A variable is the characteristic or attribute of an individual, group, educational system, or the environment that is of interest in a research study. Variables can be straightforward and easy to measure, such as gender, age, or course of study. Other variables are more complex, such as socioeconomic status, academic achievement, or attitude toward school. Variables may also include an aspect of the educational system, such as a specific teaching method or counseling program. Characteristics of the environment may also be variables, such as the amount of school funding or availability of computers. Therefore, once the general research topic has been identified, the researcher should identify the key variables of interest.

For example, a researcher is interested in low levels of literacy. Literacy itself is still a broad topic. In most instances, the broad topic and general variables need to be specifically identified. For example, the researcher needs to identify specific variables that define literacy: reading fluency (the ability to read a text out loud), reading comprehension (understanding what is read), vocabulary, interest in reading, etc. If a researcher is interested in motivation, what specific motivation variables are of interest: external motivation, goals, need for achievement, etc? Reading other research studies about your chosen topic will help you better identify the specific variables of interest.

Identifying the key variables is important for the following reasons:

The key variables provide focus when writing the Introduction section.
The key variables are the major terms to use when searching for research articles for the Literature Review.
The key variables are the terms to be operationally defined if an Operational Definition of Terms section is necessary.
The key variables provide focus to the Methods section.
The Instrument will measure the key variables. These key variables must be directly measured or manipulated for the research study to be valid.

Research Design

After the key variables have been identified, the researcher needs to identify how those variables will be studied, which is the heart of the research design. There are four primary research designs:

Descriptive: Describes the current state of variables. For example, a descriptive study might examine teachers' knowledge of literacy development. This is a descriptive study because it simply describes the current state of teachers' knowledge of literacy development.
Causal Comparative: Examines the effect of one variable that cannot be manipulated on other variables. An example would be the effect of gender on examination malpractice. A researcher cannot manipulate a person's gender, so instead males and females are compared on their examination malpractice behavior. Because the variable of interest cannot be manipulated, causal comparative studies (sometimes also called ex post facto) ccompare two groups that differ on the independent variable (e.g., gender) on the dependent variable (e.g., examination malpractice). Thus, the key identifying factor of a causal comparative study is that it compares two or more groups on a different variable.
Correlational: Describes the relationship between variables. Correlational studies must examine two variables that have continuous values. For example, academic achievement is a continuous variable because students' scores have a wide range of values - oftentimes from 0 to 100. However, gender is not a continuous variable because there are only two categories that gender can have: male and female. A correlational study might examine the relationship between motivation and academic achievement - both continuous variables. Note that in a correlational design, both variables must be studied within the same group of individuals. In other words, it is acceptable to study the relationship between academic achievement and motivation in students because the two variables (academic achievement and motivation) are in the same group of individuals (students). However, it is extremely difficult to study two variables in two groups of people, such as the relationship between teacher motivation and student achievement. Here, the two variables are compared between two groups: teachers and students. I strongly advise against this latter type of study.
Experimental and Quasi-Experimental: Examines the effect of a variable that the researcher manipulates on other variables. An experimental or quasi-experimental study might examine the effect of telling stories on children's literacy skills. In this case, the researcher will "manipulate" the variable of telling stories by placing half of the children in a treatment group that listens to stories and the other half of children in a control group that gets the ordinary literacy instruction. The difference between an experimental design and quasi-experimental design is described in Step 4: Research Design.

Descriptive studies are the most simple research design and provide the least amount of information about improving education. Therefore, descriptive studies should only be conducted for first degree and diploma projects. Only in special cases should a Masters thesis be descriptive. Doctoral dissertations should aim for experimental or quasi-experimental studies.

Once the key variables and the research design have been identified, the rest of the study falls into place.

The purpose, research questions, and hypotheses will be written about the variables based on the research design.
The Instruments will be developed to measure the key variables and the Instruments section in Chapter 3 is written to describe the instruments.
The Procedures section describes the treatment for experimental studies and/or how the instrument will be administered.
The Method of Data Analysis describes how the data is summarized and tested based on the research questions and hypotheses.

Thus, the most difficult part of planning the research study is identifying the research variables and research design. Considerable time and thought needs to be given to this step. Once the key variables have been identified, then the research study can be developed. It is important to develop the research study as described in Chapter 3 before writing the paper. If thought is not given to how the research study should be conducted, then a researcher might spend considerable time and energy developing a Chapter 1 and Chapter 2 for a project that is completely unresearchable. Therefore, it is best to refine the research study before spending the effort to write the first two chapters.

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