1. Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland;
2. Cleveland Clinic Center for Spine Health, Cleveland Clinic, Cleveland;
3. Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio
4. Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio;
5. Department of Neurosurgery, Inova Health System, Falls Church, Virginia;
6. London School of Economics and Political Science, London, United Kingdom; and