In this module, the four approaches to quantitative research are described and examples are provided.

Learning Objectives

• List and explain the four approaches to quantitative research
• Provide an example of each method
• Describe how to identify the appropriate approach for a particular research problem

There are four main types of quantitative research designs: descriptive, correlational, quasi-experimental and experimental. The differences between the four types primarily relates to the degree the researcher designs for control of the variables in the experiment. Following is a brief description of each type of quantitative research design, as well as chart comparing and contrasting the approaches.

A Descriptive Design seeks to describe the current status of a variable or phenomenon. The researcher does not begin with a hypothesis, but typically develops one after the data is collected. Data collection is mostly observational in nature.

A Correlational Design explores the relationship between variables using statistical analyses. However, it does not look for cause and effect and therefore, is also mostly observational in terms of data collection.

A Quasi-Experimental Design (often referred to as Causal-Comparative) seeks to establish a cause-effect relationship between two or more variables. The researcher does not assign groups and does not manipulate the independent variable. Control groups are identified and exposed to the variable. Results are compared with results from groups not exposed to the variable.

Experimental Designs, often called true experimentation, use the scientific method to establish cause-effect relationship among a group of variables in a research study. Researchers make an effort to control for all variables except the one being manipulated (the independent variable). The effects of the independent variable on the dependent variable are collected and analyzed for a relationship.

When deciding on the appropriate approach, the Decision Tree from Ebling Library may be helpful. The following video, Quantitative Research Designs, further describes the differences between quantitative research approaches and offers tips on how to decide on methodology.

Suggested Readings

Bernard, H. R., & Bernard, H. R. (2012). Social research methods: Qualitative and quantitative approaches. Sage.

Creswell, J. W. (2013). Research design: Qualitative, quantitative, and mixed methods approaches. Sage publications.

Gall, M. D., Borg, W. R., & Gall, J. P. (1996). Educational research: An introduction . Longman Publishing.

Mertens, D. M. (1998). Research methods in education and psychology: Integrating diversity with quantitative & qualitative approaches.

Neuman, W. L., & Neuman, W. L. (2006). Social research methods: Qualitative and quantitative approaches.

Punch, K. F. (2013). Introduction to social research: Quantitative and qualitative approaches. Sage.