1. Division of Vascular and Endovascular Surgery, Boston Medical Center, Massachusetts, USA
2. Division of Vascular and Endovascular Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
3. Division of Vascular and Endovascular Surgery, New York-Presbyterian Hospital, Weill Cornell Medical College, New York, USA
4. Department of Biostatistics, Boston University, School of Medicine, Massachusetts, USA