The most important methodological choice researchers make is based on the distinction between qualitative and quantitative data. As mentioned previously, qualitative data takes the form of descriptions based on language or images, while quantitative data takes the form of numbers.
Qualitative data is richer and is generally grounded in a subjective and interpretivist perspective. However, while this is generally the case, it is not always so. Qualitative research supports an in-depth understanding of the situation investigated and, due to time constraints, it generally involves a small sample of participants. For this reason the findings are limited to the sample studied and cannot be generalised to other contexts or to the wider population. Popular methods based on qualitative data include semi-structured or unstructured interviews, participant observations and document analysis. Qualitative analysis is generally more time-consuming than quantitative analysis.
Quantitative data, on the other hand, might be easier to collect and analyse and it is based on a large sample of participants. Quantitative methods are based on data that can be ‘objectively’ measured with numbers. The data is analysed through numerical comparisons and statistical analysis. For this reason it appears more ‘scientific’ and may appeal to people who seek clear answers to specific causal questions. Quantitative analysis is often quicker to carry out as it involves the use of software. Owing to the large number of respondents it allows generalisation to a wider group than the research sample. Popular methods based on quantitative data include questionnaires and organisational statistical records among others.
The choice of which methodology to use will depend on your research questions, the formulation of which is consequently informed by your research perspective. Generally, unstructured or semi-structured interviews produce qualitative data and questionnaires produce quantitative data, but such a distinction is not always applicable. In fact, language-based data can often be translated into numbers; for example, by reporting the frequency of certain key words. Questionnaires can produce quantitative as well as qualitative data; for example, multiple choice questions produce quantitative data, while open questions produce qualitative data.