Procedure
Focus groups were held until saturation of new information was reached, as in qualitative research sample size can never be pre-determined. To be sure we did not miss any ‘new’ information, one additional focus group session was held after theoretical saturation was estimated. All focus groups were organised at the Faculty of Physical Education and Physiotherapy of the Vrije Universiteit Brussel (Brussels, Belgium) at a time and date convenient for the students and researchers. Before each focus group all participants were asked to complete a short questionnaire, including demographics, height, weight and perceived health (see Table 1). Furthermore, explanation about the aim of the study was given and an informed consent (in which participants’ anonymity and confidentiality were assured) was signed by each participant. Each focus group lasted between 90 and 120 minutes (including questions about physical activity and sedentary behaviour which were not included in this paper) and was facilitated by a moderator and an assistant moderator (observer), who took notes during the discussions and made sure the moderator did not overlook any participants trying to add comments. All focus group discussions were audiotaped with permission of the participants. Drinks and snacks were provided during the focus group discussions. Afterwards, all students received an incentive (a lunch voucher). The study was approved by the Medical Ethical Commission of the university hospital.