How do qualitative and quantitative research methods differ?

Qualitative research focuses on understanding concepts and experiences, while quantitative research is about numerical data and statistical analysis.

Qualitative research is a method that is used to gain an understanding of underlying reasons, opinions, and motivations. It provides insights into the problem or helps to develop ideas or hypotheses for potential quantitative research. Qualitative research is also used to uncover trends in thought and opinions, and dive deeper into the problem. This type of research is often exploratory and unstructured, using methods such as focus groups, individual interviews, and participation/observations. The results of qualitative research are descriptive rather than predictive.

On the other hand, quantitative research is used to quantify the problem by way of generating numerical data or data that can be transformed into usable statistics. It is used to quantify attitudes, opinions, behaviours, and other defined variables – and generalise results from a larger sample population. Quantitative research uses measurable data to formulate facts and uncover patterns in research. It is often more structured than qualitative research methods and includes methods such as surveys and questionnaires or equipment to collect numerical data.

In essence, qualitative research is about 'why' and 'how', seeking to understand human behaviour and the reasons that govern such behaviour. It's about digging below the surface to understand the complexities of a particular phenomenon. Quantitative research, however, is about 'how many' or 'how much', and is used when we want to predict or generalise from our findings. It's about measuring the incidence of various views and opinions in a chosen sample.

Both methods have their strengths and weaknesses and can be used to complement each other. For example, qualitative research can help to formulate hypotheses and design the questionnaire for a quantitative study. Conversely, quantitative findings can help to inform the design of qualitative research, such as the selection of participants for a focus group or interview.