ESR News August 2015

Justification of exposure and referral guidelines for imaging

John Damilakis, Professor of Medical Physics

The International Commission on Radiological Protection (ICRP) system of radiation protection is based on three fundamental principles: justification, optimisation and dose limitation (1). The principle of justification requires that all medical exposure to ionising radiation must be justified. When selecting an x-ray imaging procedure, the benefit/risk balance must be carefully considered.

The Bonn Call-for-Action (2) highlights ten main actions identified as being essential for the strengthening of medical radiation protection over the next decade. Action 1 focuses on the implementation of the principle of justification. The main sub-actions of Action 1 are:

  1. a) Introduce and apply the 3A’s (awareness, appropriateness and audit), which are seen as tools that are likely to facilitate and enhance justification in practice
  2. b) Develop harmonised, evidence-based criteria to strengthen the appropriateness of clinical imaging, including diagnostic nuclear medicine and non-ionising radiation procedures, and involve all stakeholders in this development
  3. c) Implement clinical imaging referral guidelines globally, keeping local and regional variations in mind, and ensure regular updating, sustainability and availability of these guidelines
  4. d) Strengthen the application of clinical audit in relation to justification, ensuring that justification becomes an effective, transparent and accountable part of normal radiological practice
  5. e) Introduce information technology solutions, such as decision support tools in clinical imaging, and ensure that these are available and freely accessible at the point-of-care
  6. f) Further develop criteria for justification of health screening programmes for asymptomatic populations (e.g. mammography screening) and for medical imaging of asymptomatic individuals who are not participating in approved health screening programmes (e.g. use of CT for individual health surveillance).


The European Commission launched a project on ‘Referral Guidelines for Imaging’ in 2011. Referral guidelines for medical imaging are decision-support tools developed to support referring physicians and practitioners for improving appropriateness and justification of radiological procedures. The professional organisations involved in the project included the European Society of Radiology (ESR) as coordinator, the Royal College of Radiologists (RCR), the Société Française de Radiologie (SFR), the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) and the European Society of Paediatric Radiology (ESPR). The objective of this project was to review the situation in the EU Member States regarding the fulfillment of their obligations under the Medical Exposure Directive Article 6.2 (97/43/EURATOM), which requires Member States “to ensure that recommendations concerning referral criteria for medical exposure, including radiation doses, are available to the prescriber of medical exposure”.

The main activity of the ‘Referral Guidelines for Imaging’ project was to conduct an EU-wide survey on the availability, development and implementation of referral guidelines for radiological imaging in the EU Member States. Survey results indicated that a) there is strong support for the concept of integrating guidelines into clinical decision support (CDS) systems, b) there is a need for European measures to encourage both availability and use of referral guidelines and c) there is a need for European Guidelines. These may be produced initially by a combination of existing national Guidelines, developed using accepted methodology, under the auspices of a European professional organisation.

The ESR has started developing European imaging referral guidelines based on the Appropriateness Criteria developed by the American College of Radiology (3). The guidelines will be embedded into the ESR iGuide CDS platform for distribution in Europe. Through embedding these guidelines in the CDS platform, users will be able to localise the recommendations according to their needs starting from the evidence-based core. More information about ESR iGuide can be found at



  1. The 2007 Recommendations of the International Commission on Radiological Protection. ICRP publication 103. In Ann ICRP.2007; 37(2-4).
  2. Bonn Call-for-Action. Joint Position Statement by the IAEA and WHO. Full text of the statement can be found at
  3. American College of Radiology (ACR) ‘Appropriateness Criteria’. Information can be found at