Sacks David A
Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, California, USA Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Southern California, Keck School of Medicine, Los Angeles, California, USA
BMJ. 2015 Jan 21;350:h177. doi: 10.1136/bmj.h177.