About the Authors
Center for Tobacco Control Research and Education, University of California San Francisco, San Francisco, California , United States of America
Graduate School of Public Health, San Diego State University, San Diego, California, United States of America
The authors have declared that no competing interests exist.
ICMJE criteria for authorship read and met: JSY TEN. Wrote the first draft of the paper: JSY. Contributed to the writing of the paper: JSY TEN. Conceptualized the project and prepared the manuscript: JSY TEN.