Minimizing Interrater Variability in Staging Sleep by Use of Computer-Derived Features Minimizing Interrater Variability in Staging Sleep by Use of Computer-Derived Features Download In Memoriam: Thomas E. Meade, DDS, 1941–2016 Obstructive Sleep Apnea Increases the Perioperative Risk of Cardiac Valve Replacement Surgery: A Prospective Single-Center Study