Although I talked about many benefits of mixed methods in my previous blog there are also many limitations as well. In this blog I will explain some of the more prominent disadvantages as well as writing a short list of disadvantages to sum it all up.
One of the main disadvantages of this design is that when you quantitize qualitative data it loses its flexibility and depth, which is one of the main advantages of qualitative research. This occurs because qualitative codes are multidimensional (Bazeley, 2004) while quantitative codes are one-dimensional and fixed so basically changing rich qualitative data to dichotomous variables produces one dimensional immutable data (Driscoll et al., 2007). It is possible for a researcher to avoid quantitizing qualitative data but it can become very time-consuming and complex process as it requires analysing, coding and integrating data from unstructured to structured data (Driscoll et al., 2007).
Another problem associated with mixed method design is the possible statistical measurement limitations of qualitative data when it has been quantitized as quantitized qualitative data is very vulnerable to collinearity (Roberts, 2000). Researchers having to collect and analyse qualitative data may reduce their sample size for the design to be less time-consuming and doing so can affect statistical procedures like analyses of variance and t-tests. This is a serious challenge for this design as the researcher may not have enough statistical power to support their research (Driscoll et al., 2007). Although this can be avoided if the researcher decides not to conduct a mixed method design that involves quantitization.
Weaknesses of Mixed Method Design (Onwuegbuzie & Johnson, 2004)
• Time Consuming & Expensive.
• Difficult finding a researcher with experience in both qualitative and quantitative research.
• Researcher has to learn multiple methods and be able to know how to mix each method effectively.
• Methodological purists believe that a researcher should either pick the qualitative or quantitative paradigm and not both.
• How to interpret conflicting results & analysing quantitative data qualitatively still need to be figured out.
In conclusion mixed method design can an effective design to use but only if the researcher is well versed in both quantitative and qualitative research methods and also knows how to avoid the major challenges of the design (e.g. collinearity). For a researcher to be able to understand all these different methods and approaches it would become very time-consuming and expensive which may discourage many researchers.