Letter to the editor

Affiliations

• ¹ College of Health and Public Service, University of North Texas, Denton, TX, USA; Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, CA, USA. Electronic address: julia.heck@unt.edu.
• ² Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, CA, USA.
• ³ University of Southern California, Los Angeles, CA, USA.