The treatment preferences of adolescents and their parents, what has the smile RCT shown us? Smile: specialist medical intervention and lightning evaluation

Results Content analysis revealed that most parents and adolescents did not express strong treatment preferences in recruitment consultations prior to randomisation. However, interviews suggested preferences were held but not expressed. We identified the following themes: 1. CONFLICTING PARENT-CHILD PREFERENCE: Most mothers had a stronger and more polarised preference. Adolescents expressed a preference more often if interviewed alone. 2. REASONS FOR PREFERENCE: Mothers wanted: extra treatment and “keeping options open”. Some discussed: “nothing to lose”; financial hardship and education. Adolescents preference was based on; feeling tired; anxiety; meeting new people; treatment was already helping. 3. UNDERSTANDING RANDOMISATION. Most demonstrated a good understanding of randomisation although many used terms such as ‘lucky’ and ‘chosen’. 4. ALLOCATION DISAPPOINTMENT. Parental disappointment led to changes in communication during recruitment consultations.