Qualitative, Quantitative and Mixed-Methods research designs are points along a spectrum: with Qualitative and Quantitative on either end and Mixed-Methods in the middle. Quantitative research focuses on specific, measurable data, using lists of predetermined values to collect data. Quantitative research tries to support or refute existing theories. Qualitative research has its focus on discovery, and instead of constraining itself to predefined metrics, takes a broader scope approach, and develops its theories based on the data unearthed in the process of research (Creswell, 2009, p. 4)
The Mixed-Methods approach combines qualitative and quantitative research (Creswell, 2009, p. 4).
Quantitative strategies include survey research: in which trends, attitudes or opinions are determined by studying a portion of that population or experimental research, in which a specific factor is tested to determine its influence on an outcome (Creswell, 2009, p. 12).
Qualitative strategies include:
Ethnography, in which a cultural group is studied in their natural setting over a prolonged period of time (Creswell, 2009, p. 13);
Grounded Theory, in which theories are derived from studying the views of the participants (Creswell, 2009, p. 70);
Case Studies, in which detailed observation over a sustained period of time allows exploration of a specific program, activity, event or process (Stake, 1995, cited in Creswell, 2009, p. 13);
Phenomenological and Narrative research are those strategies in which theories are developed based on descriptions provided. The significant difference between the two, is that in the former, the descriptions are provided exclusively by the participants, whereas in the latter, the researcher combines his or her views with those of the participants (Clandinin & Connelly, 2000, as cited is Creswell, 2009, p. 13).
Mixed-Methods strategies include two which are temporally-focused, and one in which a perspective guides the study (Creswell, 2009, p. 66).
In using sequential strategies, a researcher uses one method to expand or elaborate on the findings of another, one after the other (Creswell, 2009, p. 14). In concurrent strategies, both qualitative and quantitative data are collected at the same time, and are then integrated at the end of the study to determine the result (Creswell, 2009, pp. 14-15). It is the transformative strategy in which an overarching perspective provides the framework for the study. In a transformative strategy, both sequential and concurrent strategies may be subsumed or interpolated (Creswell, 2009, p. 15, 66).
Research approaches are selected based on the researcher’s philosophical assumptions, worldview or paradigm (model) (Creswell, 2009, p. 5).
Post-positivism does not accept the positivist precept regarding the absolute value and truth of knowledge. It uses the scientific method of inquiry, “…in which causes probably [emphasis added] determine effects or outcomes” (Creswell, 2009, pp. 6-7). It is best suited for quantitative research designs.
Social constructivism is a qualitative research approach in which “…subjective meanings… are…formed through interactions with norms that operate in people’s lives” (Creswell, 2009, p. 8).
Advocacy/Participative is an issue-based approach which contains an activist agenda. It arose in the last two decades of the twentieth century in reaction to a perceived need that social change and steps toward improving social justice were underserved or ineffectively addressed by precursor approaches, particularly the post-positivist (Kemmis and Wilkinson, 1998, cited in Creswell, 2009, p. 10). This approach would work well with qualitative or mixed-methods research designs.
Pragmatism is solutions-focused. It is not committed to any particular paradigm or theoretical lens, and is thus readily adaptable to different problem-sets. It is well suited for mixed-methods research designs (Creswell, 2009, p. 11).
Although there are some fundamental differences between qualitative and quantitative research, it is based at the level of assumptions about the nature of research itself, “…rather than at the level of the data…Many qualitative researchers operate under different epistemological assumptions [emphasis added] [about what is ultimately knowable] from quantitative researchers…” whereas “…[m]any qualitative researchers…operate under different ontological assumptions [emphasis added] [about the true nature of reality] (Trochim, 2006). Epistemology is where post-positivism diverged from positivism. Ontology tries to determine whether or not all reality is subjective (shaped by personal perception), or if there is truly a dichotomy between objective (pre-existing and unaffected by individual perception) and subjective reality.
The “…’mixed methods’ approach” can be applied in most research, as “…[a]ll qualitative data can be coded quantitatively…[a]nything that is qualitative can be assigned meaningful numerical values…” and that “…quantitative data is based on qualitative judgement. Numbers in and of themselves can’t be interpreted without understanding the assumptions which underlie them” (Trochim, 2006).
Where “[q]ualitative research explores attitudes, behavior and experiences through such methods as interviews or focus groups…” attempting to get in-depth opinions from participants, “[q]uantitative research…reaches many more people, but the contact with those people is much quicker than it is in qualitative research” (Sanchez, 2006).
“Qualitative research is ideal for earlier phases of research projects while the for the latter part of the research projects, quantitative research is highly recommended” (Comparing Quantitative and Qualitative Research, 2009). Qualitative research can be used initially to identify patterns, and then later (sequentially) quantitative research can be used to attempt to measure and refine those patterns previously identified.
REFERENCES
Comparing Quantitative and Qualitative Research (2009). Experiment-Resources.com. Retrieved 6 January 2011 from http://www.experiment-resources.com/quantitative-and-qualitative-research.html
Creswell, J. (2009). Research Design: Qualitative, Quantitative and Mixed Method Approaches. SAGE Publications, Inc. Thousand Oaks: CA.
Sanchez, A. (2006, August). The Difference Between Qualitative and Quantitative Research. Retrieved 6 January 2011 from http://e-articles.info/e/a/title/THE-DIFFERENCE-BETWEEN-QUALITATIVE-AND-QUANTITATIVE-RESEARCH/
Trochim, W. (2006, October 20). The Qualitative Debate. Retrieved 6 January 2011 from http://www.socialresearchmethods.net/kb/qualdeb.php
