Objectives: The FiCTION trial compared co-primary outcomes (dental pain and/or infection) and secondary outcomes (child oral health-related quality of life [COHRQOL], child dental anxiety, cost-effectiveness, caries development/progression and acceptability) across three treatment strategies (Conventional with Prevention [C + P]; Biological with Prevention [B + P]; Prevention Alone [PA]) for managing caries in children in primary care. COHRQOL and child dental anxiety experiences are reported upon here.Methods: A multi-centre, 3-arm, parallel-group, unblinded patient-randomized controlled trial of 3- to 7-year-olds treated under NHS contracts was conducted in 72 general dental practices in England, Wales and Scotland. Child participants (wi...