18 Use of CT in asymptomatic people for individual health assessment (IHA): a framework to improve clinical governance and regulatory compliance

Objective Justification is a key principle of radiation protection in medicine: it requires that, among other things, all radiological procedure must provide more benefit than harm. While medical imaging has improved patient care, a substantial fraction of exams is unjustified and does not provide a net benefit. Computed tomography (CT) is used increasingly for imaging asymptomatic people for individual health assessment (IHA). This arises, for example, in some instances of use of CT for coronary artery calcium scoring, early detection of lung and colon cancers, and whole-body surveys. These practices are often performed outside formally organized screening programmes, and the evidence for their benefits and harms is usually weak or absent. They are often not part of established healthcare pathways, arrangements for transferring results from them to the healthcare system are usually absent, and quality assurance programmes are seldom in place. Method WHO organized international workshops in 2014 (Munich), 2016 (Seoul), 2017 (Quebec) and 2018 (Copenhagen), and stakeholders’ feedback was collected. The new International Radiation Basic Safety Standards (BSS) were considered in these deliberations. The BSS require that all radiological procedures on asymptomatic individuals, which are not part of approved health screening programmes, be justified by the practitioners involved, and that the individual presenting be informed of the expected potential benefits, potential harms and limitations. Based on these an international expert group published a paper identifying the issues and options open to policy makers and practitioners. The role of both health authorities and radiation regulators was addressed. Concerns included justification and appropriateness of procedures, safety, quality, process evaluation, optimization, protocols, staff education, training, performance, documentation, mechanisms for integrating the results into established care pathways, ethics and health economics issues, information on benefits, harms and other outcomes to citizens, patients and professionals. Results Structured definitions and descriptions of CT-IHA practices have been developed, described and compared with more formal radiation screening programmes. In addition, these definitions/descriptions are reviewed in the context of more widespread screening activities in medicine and public health. The considerations involved go beyond radiation-induced cancer risks, and the obvious radiation related legal and good practice requirements. They include public health, ethics, over-diagnosis, over-treatment, false positives, false negatives, indeterminate results and incidental findings, among others. A framework is presented to assist policy development by health authorities, radiation protection regulators, and other relevant stakeholders. It provides for improving clinical governance and regulatory compliance. Notable uncertainties are involved in treating both benefits and harms as well as in the overall experience of persons in receipt of CT-IHA, and these are addressed. This paper summarizes the structure and content of the new WHO document.