1. Johns Hopkins School of Medicine, Department of Physical Medicine and Rehabilitation, Baltimore, MD, United States
2. Department of Pediatrics, Oregon Health Sciences University School of Medicine, Portland, OR, United States
3. Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
4. Department of Orthopedic Surgery, Johns Hopkins School of Medicine, Baltimore, MD, United States
5. Centre for Pain Research, University of Bath, Bath, United Kingdom
6. Cochrane Pain, Palliative and Support Care Review Group, Oxford, United Kingdom