Paul A Anderson1, Robert B Conley2. 1. Department of Orthopedic Surgery & Rehabilitation, University of Wisconsin, UWMF Centennial Bldg, 1685 Highland Ave, 6th floor Madison, WI 53705-2281, USA. Electronic address: anderson@ortho.wisc.edu. 2. Center for Medical Technology Policy, 401 E Pratt St, Suite 631, Baltimore, MD, 21202, USA. Electronic address: robert.conley@cmtpnet.org.