[1] Stanford Univ, Dept Anesthesia, Sch Med, Stanford, CA 94305 USA
[2] Univ Louisville, Outcomes Res Inst, Louisville, KY 40292 USA
[3] Univ Louisville, Dept Anesthesiol & Perioperat Med, Louisville, KY 40292 USA
[4] Cleveland Clin, Dept Quantitat Hlth Sci, Cleveland, OH 44106 USA
[5] Cleveland Clin, Dept Outcomes Res, Cleveland, OH 44106 USA
[6] Columbia Univ, Dept Anesthesiol, New York, NY USA
[7] Outcomes Res Consortium, Cleveland, OH USA