Universidad de los Andes, Colombia - School of Medicine, Universidad de los Andes, Colombia - School of Medicine, Universidad de los Andes, Colombia - School of Medicine, Universidad de los Andes, Colombia - Department of Industrial Engineering, Universidad de los Andes, Colombia - Department of Industrial Engineering, Pontificia Universidad Javeriana - School of Education, Universidad de los Andes, Colombia - School of Medicine, University of the North - Department of Civil and Environmental Engineering, Universidad de los Andes, Colombia - Department of Civil and Environmental Engineering, Drexel University - Urban Health Collaborative, University of California, Berkeley - Department of City and Regional Planning and Institute for Transportation Studies and Drexel University - Urban Health Collaborative