A feasibility study of 'The StepSmart Challenge' to promote physical activity in adolescents. - Corepal, Rekesh; Best, Paul; O'Neill, Roisin; Kee, Frank; Badham, Jennifer; Dunne, Laura; Miller, Sarah; Connolly, Paul; Cupples, Margaret E.; van Sluijs, Esther M. F.; Tully, Mark A.; Hunter, Ruth F. (Pilot & Feasibility Studies, 2019)