Quantitative and qualitative research methods are similar primarily because they are both methods of research that are limited by variables. Additionally, qualitative and quantitative research methods can be used to study the same phenomenon. However, qualitative research is most often used to study people, while quantitative research typically measures the frequency or total of something. Regardless, both methods are often capable of investigating the same hypothesis.
For example, a qualitative study can gather information on the effectiveness of welfare policies by analyzing self-reported financial information from welfare recipients. On the other hand, quantitative research can be used to look at the financial situations of the same recipients by analyzing financial documents. Both studies analyze the same kind of information and investigate the same question. However, the information that is being analyzed is what is different.
Qualitative and quantitative research methods are also similar because both methods are limited by variables. In the previous example, the qualitative research method is limited because self-reported information is not always accurate. The quantitative research method is also limited because not all financial information is always documented.
Lastly, both research methods are similar because both methods are affected by the researcher conducting the research. For example, each researcher chooses which information to gather and how to interpret the data. This has a significant impact on the outcome of research, regardless of which method is used.