Respondents
SECONDARY, RECRUITMENT
We approached 23 eligible participants by telephone, of which 18 agreed to receive further information. Two parents and one child declined to participate either for unknown reasons, personal circumstances or not wanting to talk (one each). Data saturation first appeared after 10 interviews when we had only interviewed 1 child aged ≥12 years and 1 father. Therefore, we continued purposive recruitment of these groups for an additional five interviews to improve representation and saturation. Unfortunately, only 1 more child was recruited. All interviews took place within 2 months after the initial presentation. 
Parents’ and children’s characteristics (n=15)*Clinician reported†Patient reported‡Educational level was divided in low (primary and lower secondary education), intermediate (secondary (vocational) education) and high (Bachelor’s degree or higher).