text: Acknowledgements 
  The authors wish to acknowledge Dr. Roger B. Fillingim and Dr. Nicole M. 
  Marlow for their input on study design and analysis. OPT-IN Network 
  Participants included: University of Florida: Joel Bialosky; UF Health: Giorgio 
  Zeppieri, Jr., Daniel Broome, Marty Huegel, Debi Jones, Steve Emery, Mike 
  Hodges, Derek Miles, Jodi Davis, Charlene Stubbington, Mike Darcy; ATI 
  Physical Therapy: Ellen Shanley, Thomas Denninger, Jenna Bartsokas, Elise 
  Harris, Jordan Floyd, Wade Harrell; University of Southern California: Lori 
  Michener, Amy Pomrantz, Brooks Rehabilitation: Raine Osborne, Nata 
  Salvatori, John Leschitz, Brian Hagist, Laura Langer, Tim Shreve, Nando 
  Malaman, Michael Bourassa, Justin Zych, Tasha Mouton Shanklin; University 
  of Illinois at Chicago: Aaron Keil, Brad Myers, Deb Davey, Justin Payette, 
  Adam Wielechowski, Richard Severin, Erik Martinez; Indiana State University: 
  Ryan Hanigan, Carolina Valencia, Danielle Jena, Nicole Woodard; Arcadia 
  University: Angela Tate; Life’s Work Physical Therapy: Sandra Stryker, Aaron 
  Leonard, Erin Courtney, Brandon Little, Kathryn Jankord, Brad Simpson, 
  Charleen Hall, Paige Nixon, Julia Neufeld; University of Colorado, Denver: Paul 
  Mintken, Virginia Arnette, Andrea Barsch. 