There were 45 American student participants, using an opportunity sample. The students were split into 5 groups, 9 in each group.
The participants were shown 7 film clips of different traffic accidents in a random order. Following each film, they were given a questionnaire in which they were asked to give an account of the accident and were also asked a series of questions about the accident. Among those questions was the one 'critical question', which asked the participants:
'About how fast was the car going when they_______each other?'
The word used in the blank space varied from group to group. The different verbs used were: hit, smashed, collided, bumped and contacted.