Qualitative & Quantitative Research Design
Research is important in all types of industries including healthcare. Research leads to best practices, innovations, and new inventions. The two main research designs include qualitative and quantitative research designs (Oshagbemi, 2017). Critical reading and analysis of literature are essential skills in designing valid and reliable research studies. As a result, the element of critical appraisal has become a necessary part of formal postgraduate research training. In that regard, the purpose of this paper is to critically, appraise qualitative, qualitative, and quantitative research designs.
According to Ahmad et al. (2019), there is a difference in terms of the study aim/objective in qualitative and quantitative research designs. In quantitative research, the aim is stated in the form of a hypothesis that can be tested statistically. In the qualitative study design, the aim and research question focus on the questions of how? and why? rather than what? and how many? (Oshagbemi, 2017). Quantitative research aims at testing theories, demonstrating relationships between, determining facts and predicting outcomes. However, qualitative studies aim at the development and understanding of theories (Oshagbemi, 2017). Looking at the two articles, have provided more or less the same differences in terms of study aims between qualitative and quantitative studies.
According to Ahmad et al. (2019), quantitative study designs are often ranked according to the level of evidence. Normally, randomized controlled trials make the highest level of evidence. However, it is difficult to rank qualitative research in the same way based on the study design. The quality and strength of evidence in qualitative research correlate closely with the degree of rigor applied in both data collection and analysis (Ahmad et al., 2019). Regardless of whether the design is qualitative or quantitative, the study design must be appropriate to address the purpose or aim of the study, as well as answer the research question.
Sampling and sample size are other areas that require critical understanding in both qualitative and quantitative designs. In quantitative research, random sampling produces the strongest level of evidence (Ahmad et al., 2019). However, these study designs require a large amount of money and time. In addition, recruitment, especially of a cohort, can be very difficult. Furthermore, there is a significant ethical constraint relayed to the experimental designs (Oshagbemi, 2017). The appropriate sample size in a quantitative study can be calculated using a formula based on the degree of error that can be tolerated in statically testing the null hypothesis.
In the qualitative study design, the sample sizes are relatively small, and purposive sampling is often preferred. Purposive sampling involves selecting subjects because they bear certain attributes. However, in some cases, subjects with no such experiences may be included (Ahmad et al., 2019). Although quantitative researchers are free to select subjects, they must justify their selection. Sample size in a qualitative study is not calculated as quantitative but is limited by the number needed to meet data saturation. Data analysis and interpretation must be explained transparently both in the qualitative and quantitative study. However, data in the qualitative study often consists of words and their meanings rather than numbers (Oshagbemi, 2017). On the other hand, data in the quantitative study are numbers and involve statistical analysis.
Conclusion
Research is important in every sector, and healthcare is no exception. The two major research designs are quantitative and qualitative. Qualitative does not involve statistical analyses while quantitative involves numbers and statistical analyses. This paper provided a critical appraisal of qualitative and quantitative study design.