The most prominent feature of a qualitative research approach is that it asks "why" questions rather than "how" questions. A qualitative research project would not end at a discovery that, say, "9 percent of registered voters below 25 voted for John Doe while 50 percent of voters over 25 voted for John Doe." Rather, the qualitative researcher would ask why the under-25 voters and over-25 voters behaved so differently.
Another defining feature of qualitative research is the methods that it uses. Qualitative research employs a wide variety of research methods, including case study analysis, polling, interviews, and secondary source studies. Qualitative researchers will often conduct surveys (e.g. drug side effect surveys, political opinion polls) and consult with theoretical material (e.g. academic writings) to arrive at a diverse body of findings that requires analysis and interpretation.
The analysis and interpretation component of the qualitative research process often requires that the researcher make subjective judgments about the data. This is perhaps the most striking difference between quantitative and qualitative research. Whereas quantitative research arrives at numerical findings that can be analyzed through straightforward mathematical and statistical procedures, qualitative research arrives at findings that are somewhat open to subjective interpretation. To avoid biases in the interpretation of data, qualitative researchers consult with academic guidelines regarding source citation, argument structure and test construction.
Often, qualitative research produces findings that can be analyzed by a quantitative process. When conducting qualitative research, it is best to look for such opportunities wherever possible. Some quantitative research findings, such as opinion surveys, yield numerical results that can be analyzed by statistical procedures. Analyzing poll data in this fashion minimizes the risk of biased findings, and is highly recommended for quantitative researchers dealing with opinion data.
The ultimate goal of qualitative research is to synthesize findings from several sources. This is the most challenging aspect of qualitative research, because qualitative research findings come in many forms, such as poll results, empirical data, second-hand information and theory application. Qualitative researchers usually synthesize findings using specialized approaches that vary from subject to subject. For example, a sociology researcher might use poll data to critique a theory presented in a secondary source, while a psychology researcher might construct a lab experiment designed to test a theory proposed in an academic journal. The specific rules for synthesizing is a heated topic in interdisciplinary social science.