[1] Cleveland Clin, Anesthesiol Inst, Dept Outcomes Res, 9500 Euclid Ave,P-77, Cleveland, OH 44195 USA
[2] Cleveland Clin, Anesthesiol Inst, Cleveland, OH USA
[3] Cleveland Clin, Lerner Res Inst, Dept Quantitat Hlth Sci, Cleveland, OH USA
[4] Cleveland Clin, Anesthesiol Inst, Dept Gen Anesthesiol, Cleveland, OH USA