At Ad Hoc Research, we conduct groups in sizes ranging anywhere from pairs to 8 individuals, depending on specific project objectives. In some rare, specific instances, we would even work with 9 or 10. The most common group size with our client base is 6 to 8.
The research industry as a whole seems to be gravitating toward fewer rather than more participants per group. We believe this traces back to clients seeking to maximize the amount of content covered in each qualitative project in a context where research spending is closely monitored.
Therefore, we can highlight three factors to keep in mind while making that decision:
- Quantity of subject matter to cover is a primary criterion for establishing ideal group size.
- Participant profile is another key factor: for example, business people, moms with infants, or customers of a given service provider are audiences who are often very keen to expressing their opinions and therefore require more individual ‘air time’.
- Topic area is third factor to consider. Smaller groups – and even individual interviews – are advisable for more complex or sensitive topics.
In many instances where we have recommended proceeding with 6 rather than 8 participants, clients are often pleasantly surprised at the quantity and richness of content. This is despite a common client bias that more participants is better. The table below provides a list of pros and cons for both 6- and 8-participant scenarios.