A qualitative experiment is an experiment which uses a qualitative technique in order to determine the veracity of the hypothesis being tested. Various different methods of qualitative research can be used, including case studies, interviews, or diaries, and these are all linked by the fact that they aren’t objectively structured methods of collecting information. Researchers will ordinarily conduct a qualitative experiment as a way of finding a better hypothesis for a larger-scale, quantitative experiment which can more effectively provide evidence for or against the idea.
Understanding the difference between quantitative research methods and qualitative ones is the first step in understanding what a qualitative experiment is. Quantitative research is the most scientific in design and is generally concerned with having larger sample sizes and using objective methods for recording results. For example, a quantitative experiment may be conducted to determine the effectiveness of a diabetes drug by giving the drug to diabetics and taking their insulin levels to work out how effective the treatment is. A qualitative experiment, on the other hand, would be something like a case study, where one individual person is observed to learn about a condition or the effects of a treatment. Using quantitative methods is preferable to scientists because it provides more opportunity to generalize to the entire population.
Most often, a qualitative experiment will be used to get a general feel for a particular area of research before formulating a hypothesis which can be tested on a larger scale in a quantitative study. Qualitative research is inherently flawed because it only looks at a small population, and the results can’t be recorded numerically, meaning that unreliable human interpretation is at the heart of the findings. This causes a problem if a researcher wanted to generalize a finding to the entire population, because there are many different factors that could influence the results that aren’t properly controlled. A researcher may notice in a case study that the patient displayed increased anger when taking one medication, but could be erroneously linking the two things and ignoring something relevant, such as increased stress at work.
Many different methods can be used in a qualitative experiment, but the most common are case studies and interviews. These methods are characteristic of qualitative research because it is difficult to study people in large numbers through these methods and the observations of the researcher are central to the findings, even if they are at odds with the truth. Conversely, qualitative experiments provide more depth of understanding of the particular subject, and get the name from the “quality” of their findings. The use of qualitative and quantitative research methods together can therefore be used to gain a deep understanding of a topic and then test it objectively.