1. Demonstrating the Value of Orthopaedic Surgery Through Multicenter Trials by Alan S. Hilibrand, Kurt Spindler, and Regis J. O’Keefe J Bone Joint Surg Am Volume 97(7):e35 April 1, 2015 ©2015 by The Journal of Bone and Joint Surgery, Inc.

2. The percentage of collaborative multicenter studies published in orthopaedics compared with that in other fields, as found by Brophy et al.6. Alan S. Hilibrand et al. J Bone Joint Surg Am 2015;97:e35 ©2015 by The Journal of Bone and Joint Surgery, Inc.

3. Four-year SPORT primary outcomes for degenerative spondylolisthesis. Alan S. Hilibrand et al. J Bone Joint Surg Am 2015;97:e35 ©2015 by The Journal of Bone and Joint Surgery, Inc.

4. Four-year SPORT primary outcomes for lumbar spinal stenosis. Alan S. Hilibrand et al. J Bone Joint Surg Am 2015;97:e35 ©2015 by The Journal of Bone and Joint Surgery, Inc.

5. Mean direct medical costs (Fig. 4-A) and indirect costs (Fig. 4-B) for spinal stenosis (SpS), degenerative spondylolisthesis (DS), and intervertebral disc herniation (IDH) SPORT cohorts by time period and treatment received. Alan S. Hilibrand et al. J Bone Joint Surg Am 2015;97:e35 ©2015 by The Journal of Bone and Joint Surgery, Inc.