A different rhythm of life: sleep patterns in the first 4 years of life and associated sociodemographic characteristics in a large Brazilian birth cohort.

"Conflict of interest The following is the supplementary data related to this article:"

"This article is based on data from the study ‘Pelotas Birth Cohort, 2004’ conducted by Postgraduate Program in Epidemiology at Universidade Federal de Pelotas, with the collaboration of the Brazilian Public Health Association (ABRASCO). From 2009 to 2013, the Wellcome Trust supported the 2004 birth cohort study (Grant no. 086974/Z/08/Z). The World Health Organization (Grant no. 03014HNI), National Support Program for Centers of Excellence (PRONEX) (Grant no. 04/0882.7), Brazilian National Research Council (CNPq) (Grant nos. 481012-2009-5; 484077-2010-4; 470965-2010-0; and 481141-2007-3), Brazilian Ministry of Health (Grant no. 25000.105293/2004-83), and Children's Pastorate supported previous phases of the study. EN was supported by an Economic and Social Research Council (UK) GCRF Postdoctoral Fellowship (ES/P009794/1). We would like to thank Dr Rebecca Pearson and Dr Federico Torracchi for their advice on the statistical analysis."