About the Authors

Charles Preston


Affiliation Office of International Programs, US Food and Drug Administration (FDA), Silver Spring, Maryland, United States of America

Mary Lou Valdez
Katherine Bond

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Wrote the first draft of the manuscript: CP. Contributed to the writing of the manuscript: CP KB LV. ICMJE criteria for authorship read and met: CP KB LV. Agree with manuscript results and conclusions: CP KB LV.