aDivision of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA

bDepartment of Anesthesiology, Chronic Pain and Fatigue Research Center, University of Michigan, Ann Arbor, MI, USA

cOppenheimer Center for Neurobiology of Stress, Pain and Interoception Network (PAIN), David Geffen School of Medicine at UCLA, Los Angeles, CA, USA

dDepartment of Physiology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA

eDepartment of Anesthesiology, Perioperative and Pain Medicine, Division of Pain Medicine, Stanford University Medical Center, Stanford, CA, USA

fDepartments of Radiology and Anesthesiology, University of Alabama, Birmingham Medical Center, Birmingham, AL, USA

gDepartment of Urology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA

hDepartment of Urology, University of Southern California, Los Angeles, CA, USA

iDepartment of Urology, University of Iowa, Iowa City, IA, USA

jCollege of Medicine, Washington State University, Seattle, WA, USA

kDepartment of Urology, Washington University, Saint Louis, MO, USA

lNational Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, USA

mDepartment of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA

nDepartment of Urology, University of Michigan, Ann Arbor, MI, USA

*Corresponding author. Address: 24 Frank Lloyd Wright Drive, Chronic Pain and Fatigue Research Center, University of Michigan, Ann Arbor, MI 48105, USA. Tel.: 734-998-6996; fax: 734-998-6900. E-mail address: reharris@med.umich.edu (R. E. Harris).

Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article.

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.painjournalonline.com).