Research Designs

There are different ways to structure data collection in research. These procedures include both measurement issues and design issues. In both cases, the procedures can be sorted into quantitative and qualitative approaches. Generally speaking,

• Qualitative research focuses on analysis of documents, artifacts, words, pictures, and other non-numerical data. The approach is descriptive, interpretative, and subjective in nature.
• Quantitative research focuses on analysis of numerical data from quantitative variables. The approach often follows the scientific method of data collection by using designs that permit various levels of confidence in making causal inferences.

Although there are many adherents to each approach, some have posited (e.g., Trochim, 2006) that the dichotomy is actually false, at least as far as the data that are collected. For example, researchers who are by nature inclined toward the quantitative approach may utilize interviews or focus groups to explore ideas, detail theories, or develop questionnaires. Investigators who prefer a more qualitative approach may quantify interview responses into categories that are coded numerically and statistically summarized. However, the assumptions and philosophical approach of quantitative researchers are different from that of qualitative researchers. Many researchers (including those at the IUPUI Center for Service and Learning) agree that one approach is not inherently better than the other, and that a mixed-method approach is best, capitalizing on the strengths, and compensating for the weaknesses of each method. Because of the sometimes dramatic differences in approaches to research, however, mixing quantitative and qualitative methods without a clear rationale and purpose does not necessarily lead to better evidence to support research questions.

For more information on the strengths and weaknesses, pros and cons of the quantitative versus qualitative approaches, see the following web pages:

• Qualitative versus Quantitative Research: Key Points in a Classic Debate (wilderdom.com/research/QualitativeVersusQuantitativeResearch.html)
• The Assumptions of Qualitative Designs (www.gifted.uconn.edu/siegle/research/Qualitative/qualquan.htm)
• The Qualitative Debate (www.socialresearchmethods.net/kb/qualdeb.php)