(MacElroy, 2002), stating that longer questionnaires “tend to suffer significantly
from reduced user response rate.”
19.2.2 Recruiting
In lab-based usability tests, participant definition and recruitment require from
10 to 40% of the research project budget, with respect to time and resources
expended (Anonymous, 2002a). This effort is extremely worthwhile, as readers
who have ever witnessed a participant who did not meet the correct profile in a
study will attest. Inappropriate study participants can skew results, and thus their
data are typically discarded. It is common practice to over-recruit screened par-
ticipants to avoid this type of misalignment, ...