Khan, Kareem, Hollis, Chris, Hall, Charlotte L., Davies, E. Bethan, Murray, Elizabeth, Andrén, Per, Mataix-Cols, David, Murphy, Tara, Glazebrook, Cris, "Factors influencing the efficacy of an online behavioural intervention for children and young people with tics: Process evaluation of a randomised controlled trial", Journal of Behavioral and Cognitive Therapy, 2022