In view of the exploratory nature of the aims and the
complexity of the stimuli under study, the soft-laddering
technique (Grunert & Grunert, 1995; Olson & Reynolds,
2001; Russel et al., 2004) was selected to conduct the interviews.
The research team designed an interview guide to
help steer the dialogues and keep track of all elements mentioned
by subjects. The same team also pre-tested and optimised
the interview procedure through the performance of
three pilot interviews.