Quantitative Research Design
Quantitative research can be identified as the investigation of an issue by collecting statistical data through mathematical or computational techniques. Usually, scientists outline four main types of qualitative research designs, including descriptive, quasi-experimental, experimental, and correlational (Center for Innovation in Research and Teaching). The goal of the descriptive type is to observe and report the current status of an issue or a phenomenon. Within the descriptive design, researchers provide systematic information about the studied topic and develop the hypothesis after gathering the data (Center for Innovation in Research and Teaching). This type of design includes cross-sectional, longitudinal, and comparative descriptive designs.
The correlational design attempts to identify the relationships between several variables utilizing statistical data. Within this design, researchers analyze trends in existing data and do not control any of the variables (Center for Innovation in Research and Teaching). This type of research involves predictive, descriptive correlation, and model-testing designs. The quasi-experimental approach aims at establishing cause-effect relationships among the variables. Within the quasi-experimental method, the researchers do not manipulate the independent variable and measure its impact on the dependent one (Center for Innovation in Research and Teaching).
The quasi-experimental includes interrupted times-series, post-test-only, and pre-and post-test designs. Finally, within the experimental design, researchers can utilize scientific methods to establish cause-effect relationships among a group of variables (Center for Innovation in Research and Teaching). This type of quantitative research design can be referred to as true experimentation. It implies that scientists control all variables except the independent one and assign subjects to experimental treatments randomly. Common experimental designs include randomized, crossover, and nested ones.
Qualitative Research Design
Qualitative research is a method that allows for collecting non-numerical data. One of the most popular categorizations of qualitative methods includes five groups, such as grounded theory, narrative, ethnography, phenomenological, and case study (Sauro). The first type of qualitative research design aims at explaining a theory. Sample sizes for this type of design can be between 20 and 60 participants (Sauro). The purpose of a grounded theory study can be to inform design decisions.
The narrative approach analyses a sequence of events; the researcher is expected to read related documents and conduct interviews with the participants (Sauro). The narrative is not always presented in chronological order; its structure depends on the purposes of the work. The aim of such an approach can be to present the information and the challenges associated with the issue. Ethnographic studies may be considered some of the most common types of qualitative research design. Within this type of research, scientists may analyze the aspects of individuals’ characters, their goals, motivations, and values (Sauro). Sometimes, scholars become participating observers when they perform ethnographic studies.
Phenomenological studies usually describe phenomena, events, or activities. While performing this type of research, scholars can utilize various types of approaches, such as visiting significant locations, reading related documents, and conducting surveys. Notably, at the beginning of a phenomenological study, the hypothesis should not be well-formed, as the findings of the analysis can lead to changes in the authors’ perspectives (Sauro).
Finally, case studies present an in-depth evaluation or report of an event, organization, or entity. They can be descriptive, explanatory, or exploratory (Sauro). This type of qualitative research design implies that the audience can develop an excellent understanding of the cause, as it utilizes multiple data sources.
Center for Innovation in Research and Teaching. “Quantitative Approaches.” CIRT. Web.
Sauro, Jeff. “5 Types of Qualitative Methods.” MeasuringU. 2015. Web.