1 Public Health Practice, Policy, & Translational Research Department, Mel and Enid Zuckerman College of Public Health, University of Arizona, 550 E. Van Buren Street, UA Phoenix - Plaza Building 1, Phoenix AZ 850063, USA.
2 University of Arizona Cancer Center - UAHS, University of Arizona College of Medicine, Tucson, 1501 N. Campbell Avenue, PO Box 245017, Tucson, AZ 85724, USA.
3 Department of Applied Mathematics, University of Oviedo, Spain.
4 Department of Health Promotion Sciences, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, 1295 N Martin Avenue, PO Box 245209, Tucson, AZ 85724-5209.