For example, in a focus group on website usability, participants can see and navigate the site while continuing their discussions of it. As far as the technology is concerned, an online focus group could include hundreds of participants at a time. We have found, however, that in practical terms the ideal number is 8-10, very similar to traditional focus groups. Larger groups are difficult to moderate and group interaction falls off sharply. We like to have 6-8 weeks to prepare for a series of online focus groups, assuming the client and research topic are new.
Thorough preparation is the key to focus group effectiveness.