March 2018

ESR iGuide content development

The ESR iGuide content consists of imaging referral guidelines developed by the European Society of Radiology based on the American College of Radiology (ACR) Appropriateness Criteria (AC) and ACR Select content.

The ESR uses the ACR's guidelines as a starting point for reviewed and adapted guidelines for use in Europe. This review is done by the ESR Referral Guidelines Subcommittee (RG SC) that was established at ECR 2016 (originally as a working group) as part of the ESR's Quality, Safety and Standards Committee (QSSC).

The SC works with the American College of Radiology's (ACR) Rapid Response Committee (RRC) to maintain clinical decision support content based on the ACR Appropriateness Criteria. The ESR iGuide content is grouped into 10 topic areas, each headed by a dedicated expert within the RG RC.

The chair of the RG SC is charged with developing a methodology for the WG's work. The methodology for the ACR Appropriateness Criteria is the basis for the work of the ESR RG SC and is adhered to as far as applicable. The basic principles of the ESR's methodology are that any changes ESR experts make to the guidelines should be based on scientific evidence to the largest extent possible, using professional experience as well as expert opinion, judgement, and knowledge of European practice standards only as a supplement where necessary. No consideration should be given to national, local or institutional circumstances or the availability or quality of imaging equipment in certain regions or settings, as the resulting guidelines should be generally and equally applicable anywhere in Europe. From this evidence-based core, users, institutions or countries implementing ESR iGuide can make localisations to the content as necessary.

The ESR's methodology for developing imaging referral guidelines was published in Insights into Imaging in March 2019.

ESR guideline methodology


Content structure

The appropriateness of imaging exams is expressed on a numeric scale of 1 (least appropriate) to 9 (most appropriate). Exams are rated for  over 1,600 indications in ESR iGuide for a defined sex (male/female/either) and age range. The entire content set includes a further 1,700 unscored indications to be able to provide more structured reasons for exam in the clinical workflow.

The ratings are grouped into three categories:

  • 1-3 (red): usually not appropriate
  • 4-6 (yellow): may be appropriate
  • 7-9 (green): usually appropriate



The ESR iGuide content is divided into 10 different topic areas, each overseen by a dedicated expert within the WG:


ESR iGuide display evidence functionality

The ESR iGuide system provides users with the option to view the evidence used to develop the ACR and ESR guidance. This documentation includes narrative descriptions of the clinical indications, evidence tables, literature summaries, and reference lists.

As of March 2018, ESR iGuide still exclusively uses ACR documentation (which means that for some indications where ESR and ACR recommendations differ, this is not yet reflected in the evidence documentation). The ESR is currently working on a public document setting out its review methodology in detail, and documenting all instances where ESR recommendations differ from ACR ratings. This will be the basis for PDF documents used in the "display evidence" functionality in ESR iGuide.


The ESR iGuide portal provides users with actionable appropriateness feedback, and includes a "display evidence" function where users can access full ESR and ACR documentation:



ECR 2018 EuroSafe Imaging poster on guidelines

To find out more about the ESR's latest content version, check out the ECR 2018 EuroSafe Imaging poster from the ESR working group on imaging referral guidelines.

ECR 2018 ESR guideline WG poster