Aim To determine the potential of the Canadian Cervical Spine Rule (CCR) to safely reduce the number of cervical spine (c-spine) radiographs performed in the UK emergency department setting.

Methods The study was conducted in two UK emergency departments with a combined annual attendance of >150 000 adult patients. Over the 24 month trial period, 148 doctors were provided training in the use of the CCR and instructed to assess eligible patients presenting with potential c-spine injury. Doctors were instructed to manage patients according to existing practice and not according to the decision obtained from the rule. A subsample of patients was reassessed by a second doctor to test interobserver reliability.

Results A total of 1420 patients were enrolled in the study (50.4% male). 987 (69.5%) had c-spine radiography performed, with 8 (0.6%) having a c-spine injury. If the decision for radiography had been made according to the outcome of the CCR, only 815 (57.4%) would have had c-spine radiography and all 8 abnormal cases would have undergone imaging. Doctors were comfortable using the rule in 91% of cases. Interobserver reliability was good (κ=0.75 95% CI 0.44 to 1.06).

Conclusion The CCR can be applied successfully in the UK. Had the CCR been in use during the study period, a 17.4% reduction in radiography could have been achieved without compromising patient care.