Focus groups: methodology and analysis

Focus group discussions have become one of the key methods of qualitative exploration in the social sciences. They are used for different purposes in a variety of disciplinary and inter-disciplinary research settings and are generally defined as discussions held for research purposes which bring together participants to discuss topics of mutual interest to themselves and to those undertaking the research. In that they involve a collective activity, focus groups are designed to generate interaction and discussion, thereby providing the opportunity for the researcher(s) not only to ascertain shared or individual views on the topics discussed, but also to interpret their social meaning – that is, the meanings that lie behind the views that are explicitly stated.

Key features of focus groups concern, first, appropriate selection of the participants. Quantitative research requires standardization of procedures and random selection of participants to remove the potential influence of external variables and ensure generalizability of results. In contrast, subject selection in qualitative research is purposeful; participants are selected who can best inform the research questions and enhance understanding of the phenomenon being studied. Consequently, one of the most important tasks in the study design phase is to identify appropriate participants, their appropriateness being determined by the subject under investigation. Decisions regarding selection are based on the research questions, theoretical perspectives and evidence informing the study. In many studies, this will require selection of participants according to demographic characteristics such as age, gender, ethnicity, income and so on in order to ensure that participants are ‘representative’ of the category of people (for instance, members of professions, migrants or people of voting age) being investigated. Furthermore, whereas quantitative research requires statistical calculation of sample size, the sample size in qualitative research is not generally predetermined, the number of participants depending upon the number required to inform all important elements of the phenomenon being studied. Generally, the size of focus groups varies between five and twelve participants, the need for opportunity for all participants to be able to have their say being balanced against the requirement of the group or groups to reflect the representivity of the population involved.