Development and validation of the Global Adolescent and Child Physical Activity Questionnaire (GAC-PAQ) in 14 countries: study protocol oleh Tom Loney, Yang Liu, Justin Richards, Mark S Tremblay, Adewale L Oyeyemi, John J Reilly, Dale W Esliger, Karen Roberts, Melody Smith, Valerie Carson, Anuradha Khadilkar, Marie Löf, S H Wong, Diego Augusto Santos Silva, Jasmin Bhawra, Narayan Subedi, Javier Brazo-Sayavera, Alejandra Jauregui, Piyawat Katewongsa, Dyah Anantalia Widyastari, Leigh M Vanderloo, Olga Lucia Sarmiento, Taru Manyanga, Richard Larouche, Mahdi Rostami Haji Abadi, Salomé Aubert, Rachel C Colley, Christine Delisle Nyström, Ryan Harper-Brown, Silvia Alejandra Gonzalez Cifuentes, Geoff Kira, Nicholas Kuzik, Tawonga W Mwase-Vuma, Oliver W A Wilson