Objective: The objective of this article is to test the reliability and validity of the new and innovative physical activity (PA) questionnaire. Methods: Subsamples from the South American Youth/Child Cardiovascular and Environment Study (SAYCARE) study were included to examine its reliability (children: n = 161; adolescents: n = 177) and validity (children: n = 82; adolescents: n = 60). The questionnaire consists of three dimensions of PA (leisure, active commuting, and school) performed during the last week. To assess its validity, the subjects wore accelerometers for at least 3 days and 8 h/d (at least one weekend day). The reliability was analyzed by correlation coefficients. In addition, Bland-Altman analysis and a multilevel regression were applied to estimate the measurement bias, limits of agreement, and influence of contextual variables. Results: In children, the questionnaire showed consistent reliability (ρ = 0.56) and moderate validity (ρ = 0.46), and the contextual variable variance explained 43.0% with −22.9 min/d bias. In adolescents, the reliability was higher (ρ = 0.76) and the validity was almost excellent (ρ = 0.88), with 66.7% of the variance explained by city level with 16.0 min/d PA bias. Conclusions: The SAYCARE PA questionnaire shows acceptable (in children) to strong (in adolescents) reliability and strong validity in the measurement of PA in the pediatric population from low- to middle-income countries.
Bibliographical noteFunding Information:
All authors acknowledge the dean or chair of each school as well as the children, adolescents, and parents for their voluntary participation in the SAYCARE study. We also thank Mr. Andrew Mello Silva for managing the SAYCARE database. In Colombia, we thank the undergraduate students Carolina Alzate Echeverri, Luisa Fernanda Arroyave Zuleta, Sarah Lucía Ortiz Calderón, and Paola Zapata for helping collect information and for data entry. All authors thank the General Coordinator of the Growth, Exercise, Nutrition and Development Research Group, Luis A. Moreno (MD, PhD, full professor) from the Faculty of Health Sciences, University of Zaragoza, for the loan and help with the accelerometers for data collection.
Funding agencies: ACFDeM received a postdoctoral scholarship from the National Counsel of Technological and Scientific Development (CNPq; proc. 313772/2014-2) and the São Paulo Research Foundation (proc. 2014/13367-2 and 2015/14319-4). MVN-F received a PhD Student Internships Abroad scholarship from the National Counsel of Technological and Scientific Development (CNPq; proc. 200340/2015-8) and a PhD Student Brazilian scholarship from the São Paulo Research Foundation (FAPESP; proc. 2016/18436-8 and 2017/11732-3). LAM was given a visiting professor scholarship from the São Paulo Research Foundation (FAPESP; proc. 2015/11406-3). CLMF received an advanced scientist scholarship from the National Counsel of Technological and Scientific Development (CNPq; proc. 304003/2014-0). HBC received a research grant from the São Paulo Research Foundation (2014/11468-6, Research Grant for Scientific Publication Paper (2017/15560-2), and an advanced scientist scholarship from the National Counsel of Technological and Scientific Development (CNPq; proc. 300951/2015-9). The South American Youth/Child Cardiovascular and Environment (SAYCARE) study was supported mainly by the Brazilian Government from the National Counsel of Technological and Scientific Development (CNPq; proc. 471266/2013-2) and the São Paulo State Government from the São Paulo Research Foundation (FAPESP; proc. 2014/11468-6). The SAYCARE study was also cofunded by other agencies in other countries as follows: (1) Collaborative Projects Fund (R.D. N 501-2015-INSN-DG-OEA) granted by the National Institute of Child Health, Lima, Peru; (2) Sustainability Strategy at the University of Antioquia 2014-2015, Research Group of Social and Economic Determinants of Health and Nutrition, and Demography and Health Research Group at the University of Antioquia, Medellin, Colombia, and Interuniversity Services Corporation from University of Antioquia; (3) Secretary of University Extension and Student Welfare, University of Buenos Aires, Buenos Aires, Argentina; and (4) European Regional Development Fund (MICINN-FEDER) to the Growth, Exercise, Nutrition and Development Research Group. Disclosure: The authors declared no conflict of interest. Author contributions: ACFDeM, MVNF, and CLMF designed this reliability and validity study. ACFDeM, MVN-F, LAM, and HBC supervised the data analysis and interpretation. ACFDeM, MVNF, PVT-O, WVN-J, JCA, CL, CAD, and ES contributed to the data collection. AMS-P contributed to the data interpretation. All authors were involved in writing the paper and had final approval of the submitted and published versions. *Marcus Vinicius Nascimento-Ferreira and Augusto Cesar Ferreira De Moraes contributed equally to this work. Additional Supporting Information may be found in the online version of this article. Received: 16 June 2017; Accepted: 19 December 2017; Published online 21 February 2018. doi:10.1002/oby.22116