Types of Research Methods

When reading research studies, it is helpful to understand the types of research methods used by researchers because the method used influences the kind of data they collect, the way the data is analyzed, and the conclusions researchers can draw from their findings.

Research methods are divided into two main categories, quantitative and qualitative. A third type, called mixed method, includes elements of both quantitative and qualitative research studies.

Quantitative Research

In quantitative research studies, numeric data is collected and then analyzed using statistics. Quantitative studies of education practices might collect grades, test scores, or student socioeconomic status. A quantitative study could compare the student test scores of those who completed learning activities alone and those who worked with peers in small groups.

Qualitative research studies, on the other hand, collect and analyze text data such as interview transcriptions, observation notes, or historical documents. The data analysis in qualitative studies involves a process of coding the text to identify patterns and themes. For example, in a qualitative study a researcher might interview students about their experiences during small group learning activities. Then the researchers would look for themes in the interview transcripts to answer a research question about students’ views of cooperative learning activities.

In a mixed-method research study both numeric and text data are collected and analyzed. For example, a teacher might survey students about their experiences in small group learning activities and include both questions that ask students to rank their experiences on a scale, such as strongly agree to strongly disagree, and open-ended questions where students can respond in their own words. The answers that are on a scale would be recorded numerically and analyzed using statistics. The open-ended questions would be analyzed by identifying common themes in the text of the responses.

Within each of the two main categories, quantitative and qualitative research, there are several types of research. Four common types of quantitative research include:

• Experimental Research
• Causal Comparative Research
• Correlational Research
• Descriptive Research

Experimental Research: In an experimental study researchers look at the effects of a specific change in a teaching practice – called an intervention. To be a true experiment, the sample of students being studied must be randomly assigned to a group receiving the intervention or to a control group which does not experience the intervention.

Because of the random assignment, experimental research is the only research method where researchers can claim to “prove” any effect of the intervention. This is because when there is random assignment to the intervention and control groups, research protocols allow us to assume that the groups were essentially the same at the beginning of the study and to claim that any difference found between the groups was caused by the intervention and no other factor. For example, researchers could randomly assign first grade students to an intervention group that would experience a new method of reading instruction or a control group that would continue to receive the ongoing type of reading instruction. If it was found, through statistical analysis, that the new type of instruction improved reading skills more than the ongoing type of instruction, it could be concluded that the new type of instruction was better than the ongoing type of instruction.

Causal Comparative Research: Causal comparative research also looks at an intervention but uses existing groups rather than random assignment to groups. This is a more practical research method in education where it can be difficult to randomly assign students to groups because students need to be assigned to classes based on individual needs. Even though we cannot make claims about “proving” the effect of interventions in causal comparative studies, this type of research is still valuable as it provides direction for additional research and reveals potential benefits of the teaching practices researched. For example, if a causal comparative study was used to compare two types of reading instruction, researchers would want to have the same finding from multiple studies before concluding that one type of instruction would benefit students more than another type.

Correlational Research: In correlational research studies, two numeric measures are compared to determine whether they vary in a similar way. That is, when one measure increases or decreases, does the other have a similar pattern of increasing or decreasing. An example of a correlational study would be comparing mathematics test scores and the number of hours of tutoring a student received. If it was found that, in general, students who had more hours of tutoring also had higher math test scores, it could be concluded that students may benefit from the tutoring. If additional studies had the same finding, educators could be confident there is a positive correlation and that tutoring improves math achievement.

Descriptive Research: Descriptive research provides summary information about the characteristics of the sample being studied. For example, a descriptive study in education might report the number of students in categories such as gender, race, age, or grade. Descriptive studies are not used to investigate the effect of teaching practices. They only provide summary information about the sample.

Qualitative Research

In qualitative research, textual data is collected and analyzed. There are four common methods of qualitative research:

• Observations Research
• Interviews and Focus Groups Research
• Ethnographic Research
• Historical Research

Observations Research: In this type of qualitative research, the researcher makes notes while observing a particular situation or setting being researched. The researcher may look for specific behaviors being studied or may document the incidents that happen to occur during the observation. For example, if a researcher is interested in exploring evidence of student engagement during different types of mathematics instruction, the researcher could sit in the classroom during mathematics instruction and use a checklist while looking for certain evidence of student engagement. The researcher could also simply note any evidence of student engagement that happens to occur.

Interviews and Focus Groups Research: In this type of study, researchers talk to people who have experienced the situation being researched. The conversations are generally transcribed, and the text is analyzed to find themes or patterns in the data. The researcher may have a list of questions to ask the participants or may instead use spontaneous conversations where there is a more informal discussion of the topic being researched. Interviews are generally conducted with one person at a time while focus groups involve talking with multiple people at the same time. For example, a researcher collecting data on teachers’ opinions about a new social studies curriculum may interview individual teachers or hold a focus group of teachers to gather data.

Ethnographic Research: In ethnographic studies, a researcher immerses themselves in a situation to explore it from many perspectives, using multiple data collection methods. For example, to study the ways student misbehavior is handled in a school building, the researcher may take notes during observations as well as conduct interviews and focus groups to develop a comprehensive picture of the practices.

Historical Research: In historical research, past events are studied to construct an in-depth understanding of them. This would include examining documents and artifacts from the event as well as viewing video and conducting interviews, if possible. Historical studies allow researchers to develop new perspectives on past events. A researcher could look at how high school graduation ceremonies have evolved over the years by looking at materials such as program booklets and photos of past ceremonies.