How Many Participants to Choose
Q: We’re going to conduct some focus groups. How many people do I need to invite?
A: First, No matter how many people you involve in focus groups, your results will not be quantitative. The goal of focus groups is to get qualitative information on different issues. How do people see a problem? Why? What would it take to solve the problem? It’s very useful to surface these issues in open-ended focus groups and then construct a survey that will quantify how many people feel that way overall and where there are demographic variations (by location, job type, income level, etc.).
You need to conduct at least one focus group for each type of subgroup that might have a different perspective on the issue at hand. For example, if you’re asking employees questions about how communication works within your organization, you should probably have representation from people in office and manufacturing settings, people who work during night shifts, people who work at large or small locations, people at different job levels. Each of these groups experiences communication quite differently. If you don’t have a chance to talk with them, you are likely to miss very significant issues that affect large groups of people.
As a practical matter to save time and money, you then want to go to as few locations as possible to gather the greatest diversity of input. On the other hand, in many organizations you need to visit each location to conduct at least one focus group for political reasons, even though you may not hear much new information.
Angela D. Sinickas