MFQ: All participants filled in the MFQ at baseline, and 318 (68.4%) completed the MFQ at follow-up. Imputations were used to fill in missed items on submitted questionnaires (baseline: n=51, 11.0%, max number of items missed=4 out of 31; follow-up: n=26, 5/6%, max number of items missed=2 out of 31). At follow-up, imputation was also used to substitute data when the full questionnaire was missing (n=147, 31.6%).