Study protocol: The back pain outcomes using longitudinal data (BOLD) registry
Jeffrey G Jarvik*, Bryan A Comstock, Brian W Bresnahan, Srdjan S Nedeljkovic, David R Nerenz, Zoya Bauer, Andrew L Avins, Kathryn James, Judith A Turner, Patrick Heagerty, Larry Kessler, Janna L Friedly, Sean D Sullivan and Richard A Deyo