Preparing for the study

In the previous chapters, we discussed finding participants and how many participants to invite to the study. The next step is to schedule the sessions. Before doing so, the study planning needs to be reviewed, because scheduling participants requires a lot of effort, and rescheduling participants not only requires additional effort but often results in losing participants.  

Number of participants

We like to use around 10 participants per study, although we often go as low as 5 or as high as 15 participants. Since the sessions are moderated, the additional effort per participant is significant and must be taken into account in terms of the cost and schedule. 

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