Retraction to: Spinal Cord (2014) 52, 734–739; doi:10.1038/sc.2014.98; published online 10 June 2014

The Publisher and Editor retract this article in accordance with the recommendations of the Committee on Publication Ethics (COPE). After a thorough investigation we have strong reason to believe that the peer review process was compromised.

The original article was published online on 10 June 2014.