Using evidence-based imaging referral guidelines to facilitate appropriate imaging: Are they all the same?

Countries worldwide have selected, adopted, adapted, and translated evidence-based imaging referral guidelines from radiology professional bodies. This study establishes the concordance of three imaging referral guidelines from the ACR, ESR, and RCR, and examines the emergency department cervical spine imaging appropriateness rates.

A retrospective analysis of the electronic medical records was performed between October 1st to December 31st, 2022, evaluating 452 radiography and 153 CT imaging referrals. For each case, the initial clinical diagnosis was integrated with the corresponding clinical notes for analysis. Evaluation of the appropriateness rating was dichotomised to either 'indicated' or 'not indicated' for analytical and practical purposes. The inter-rater agreement for the imaging referral guidelines was calculated using Fleiss' Kappa and Cohen's Kappa.

The overall appropriateness rate of X-ray cervical spine imaging referrals was 13.3 % -75.2 %, depending on the imaging referral guidelines utilised. The appropriateness rate of CT cervical spine was 90.8 %, which was an identical rate for all three of the guidelines. Fleiss' Kappa indicated the guidelines for X-ray of the cervical spine had slight agreement (κ = 0.135 (95 % CI, 0.088 to 0.183), p < 0.001) and almost perfect agreement amongst guidelines for CT cervical spine (κ = 1.000 (95 % CI, 0.909 to 1.091), p < 0.001). For pairwise comparison, ACR AC and ESR iGuide for X-ray demonstrated moderate agreement (κ = 0.765, p < 0.001); however, RCR iRefer had no level of agreement with both. For CT, there was almost perfect agreement between all the guidelines.

The guidelines demonstrated slight agreement for X-ray cervical spine and almost perfect agreement for CT cervical spine, complicating audit process and influencing audit output. Multidisciplinary buy-in positively impacts CT cervical spine appropriateness rates. Harmonising and prioritising guideline development for commonly encountered clinical scenarios is required.