Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA *Correspondence to: Mark A. Petersen, MD, email protected. This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License (http://creativecommons.org/licenses/by-nc-sa/4.0/), which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.
Valdivia et al. (Mon,) studied this question.