Full-Scale Trial Design

An immediate full-scale superiority RCT comparing BaP-Enjoying Family Life with BaP-Standard was not recommended. A superiority trial would likely require a very large sample because both interventions showed similar outcome signals. A full-scale trial remains ethically justified despite the pilot's descriptive outcome findings. The projected scale made immediate progression to a large superiority trial costly and inefficient without first improving attendance, fidelity assessment, and acceptability measurement. Future designs could compare a refined intervention with digital-only content, use an active control arm, or consider cluster randomisation.