Trying to find participants for a focus group study can be a lot like putting together the invite list for a dinner party. Who should I invite? How will they mesh with each other? Who is going to sit next to the Cross-Fitting vegan? It can be exhausting but it’s one of the most critical pieces to recruiting a successful and informative focus group.
The number of respondents to recruit should be around eight people or slightly less, ideally. When dealing with qualitative research, you will be capturing thoughts and ideas and sentiments. People can become very passionate about a topic and if you have too many people in your focus group, not everyone will be able to share their opinions. That is like leaving money on the table.
Larger focus groups are ok when you are testing an idea or product that people do not know much about. People who are familiar with a program and use it frequently will have strong opinions about how it works more so than non-users so feel free to adjust the size of the group depending on your participants’ level of experience with your product.
If your topic is very complex or invokes a lot of passion in people, like healthcare, you should also keep the focus groups smaller. You will get a lot of information out of passion.
How many questions do you want to cover? If you have a lot of questions, invite a smaller group as well.
Keep your purpose of the study and the complexity in mind and it will guide the size of your focus group participant recruitment.