There are two types of research methods: qualitative and quantitative. Qualitative research methods are complex meaningful analyses characterized by processes and meanings that are not measured in terms of mathematical measurements. Quantitative research however, relies and builds on mathematical procedures and methods, such as frequency, quality, amount and statistical procedure. There are unique characteristics which distinguish one research process from the other. Purpose The purpose of research is to answer questions by using a “predefined set of procedures” (Mack, Woodsong, MacQueen, & Namey, 2005).
Each type of research, qualitative and quantitative, seeks to achieve this purpose with a different approach. “Qualitative research provides information about the ‘human’ side of an issue – that is, the often contradictory behaviors, beliefs, opinion, emotions, and relationships of individuals” (Mack, et al, 2005). Concerned with the “how” and “why”, it seeks to understand and describe naturally occurring phenomena. Qualitative research is approached using grounded theory, interviews, in-depth interviews, and focus groups to discover and interpret the meanings and perceptions of a specific group of people.
Qualitative research takes more of an inductive approach to theory development and usually develops a theory based on the outcome and information of the research. On the other hand, “quantitative research provides brief presentations of distributions, tables, graphs, and formula driven findings to describe, compare, and show relationships between and among a carefully defined set of variables” (Picciano, 2007). It seeks to gather numerical and statistical data using experiments, measurements, fixed-response questionnaires, and tests on a large random group.
Quantitative research tends to take more of a deductive approach and seeks hypothesis confirmation. While the purpose of qualitative and quantitative research may be the same, each has a different approach to achieving the goal. Because each type of research differs in its approach, the data it collects is different as well. Data Data is collected throughout the research project or experiment and can be collected by various instruments. It is either qualitative (descriptive) or quantitative (numerical) in nature. In qualitative research, the primary instrument for data collection is the researcher.
The data are gathered through observations, surveys, or interviews and are considered subjective because they are perceptions of the participant. Collected data may be in the form of notes, video or audio tapes, or transcripts from interviews. Qualitative research is flexible and allows adaptation of the interaction between the researcher and the participant. For example, qualitative researchers mostly ask open ended questions and these are not worded the same way with each participant. In contrast, quantitative data is obtained through instruments such as surveys or tests.
Data are collected in laboratories or through impersonal contact such as mail or telephone surveys or tests. The data obtained is quantifiable and has numerical meaning, such as a measurement or score. Research methods are objective and structured in order to ensure their measurability. Quantitative methods are generally quite inflexible. The major advantage of this very inflexibility is that it allows for the meaningful comparison of data and responses across participants. For example, a quantitative survey would require a participant to choose an answer rather than allow an open-ended discussion.
Because the data collected is either qualitative or quantitative, ensuring the accuracy of each type of data is unique to the research method. Ensuring Accuracy & Validity In order for a research project to yield accurate results, the data collected must be obtained from reliable and valid instruments. In addition, it is imperative that the results are accurately conveyed by the researcher. Because the data obtained by qualitative and quantitative research methods are different, they must be evaluated differently also.
In order to ensure the quality and establish the trustworthiness of qualitative data, researchers may call upon their peers to evaluate the narrative in order to determine if there are inconsistencies, contradictions, or other instances of researcher bias (researcher proving only that which they choose or anticipate)(Smith & Davis, 2010). Additionally, qualitative researchers also indicate the procedures they used to “validate” data. This process is called confirmability. In addition to confirmability, qualitative researchers are also concerned with credibility.
Credibility refers to the accuracy of the study. Because qualitative research is social or human in nature, it is best to allow the subjects of the study determine accuracy. However, quantitative data is evaluated in a different manner. In order to ensure that quantitative data is obtained from an acceptable instrument, it is necessary to determine the validity and reliability of the instrument being used. It is important to minimize subjectivity in quantitative research. The researcher must ensure that the surveys, questionnaires, and tests, used are not open for interpretation or the results may be skewed.
Researchers can verify the usefulness of an instrument through validity and reliability. Validity “refers to the extent to which the questions actually measure what they are supposed to measure” and can be determined by subject matter experts or by comparison on tests which are already considered valid (Giarrusso, Richlin-Klonsky, Roy, & Strenski, 2001, pg 151). Reliability refers to the consistency of the measurements and can be established by retesting the same cohort on the subject matter to see if the performance is the same.
Instruments which are neither valid nor reliable are useless to a research project. Conclusion In conclusion, there are several key differences in qualitative and quantitative research methods. Although both methods examine data to reach a conclusion, the purpose and approach used in each is different. Also different is the manner in which data is collected. Because of this, qualitative and quantitative research methods are verified by different procedures. There are many differences in these two types of research, but these are three of the most evident.