Levitan RM, Kinkle WC, Levin WJ, Everett WW. Ann Emerg Med. 2006 Jun.;47(6):548–55.
This U.S. study evaluated manipulation techniques for direct laryngoscopy during endotracheal intubation in 1,530 comparisons performed by 104 physicians in fresh cadavers. Bimanual laryngoscopy improved laryngeal view compared to cricoid pressure, backward-upward-rightward pressure, and no manipulation. JC attendees expressed considerable support for the technique of bimanual laryngoscopy where the laryngeal view was unsatisfactory.