Effectiveness and cost-effectiveness of repeated implementation intention formation on adolescent smoking initiation: A cluster randomized controlled trial

Mark Conner, Sarah Grogan, Robert West, Ruth Simms-Ellis, Keira Scholtens, Bianca Sykes-Muskett, Lisa Cowap, Rebecca Lawton, Christopher Armitage, David M Meads, Laetitia Helene Marie Schmitt, Carole Torgerson, Kamran Siddiqi