12 The introduction and demise of full body computed tomography (CT) scanning in australia: implications for preventing overdiagnosis

Abstract

Objectives Full body computed tomography (CT) scans for screening came to Australia in 2002, accompanied by a wave of advertising promising life-changing benefits without disclosing equally life-changing potential harms. Within a year, public access to self-referred full body CT screening was withdrawn as a consequence of sustained professional and political pressure and legislative changes. We examine how self-referred full body CT scans were made available to Australian consumers, and then, just as rapidly, how they were withdrawn. We evaluate and discuss the social, cultural and system factors that contributed to their de-implementation. Our analyses are intended to inform horizon scanning processes with early identification of new screening technologies that have a high risk of overdiagnosis. The aim is to encourage discussion and debate as how best to intervene to enable early identification of new testing technologies that are likely to produce unacceptable levels of overdiagnosis. Method To identify all available materials relevant to the roll out and withdrawal of full-body CT screening in Australia, systematic searches of PubMed, Factiva, ANZ Proquest, Informit, AustLii, and Pandora/Trove were undertaken for the period 1995–2014, resulting in the aggregation of 48 unique items relevant to the topic. Taken together, these databases archive media reports, advertising materials, website content, legal judgements, parliamentary proceedings, peer-reviewed journals, and government and corporate grey literatures. Sample materials were qualitatively reviewed through an iterative process of testing, revising and refining our insights and theoretical generalisations against an emerging conceptual map, and feedback from the research team. This cycle of searching, mapping and critical inquiry continued until new textual materials were not providing substantive new insights. Using the withdrawal of full body CT scans in Australia as a case example, our analyses focused on the politics and mechanisms through which a new screening technology was de-implemented. Results The rapid de-implementation of full-body CT scans in Australia arose from interconnected sociocultural and system factors, an unusual harm profile for the technology, and key contributions from people and groups within and outside of medicine. Media, legislation, health professionals, governments and regulators all played a part in a well-coordinated and joint effort. Crucially, legislation enacted for environmental protection rather than health care quality was amended to provide a mechanism for effective action. These findings can help map the challenges, pathways and mechanisms for caution about and de-implementation of future, potentially harmful, testing technologies. While the relative value of each stakeholder’s role is unclear, their collective collaboration and interaction achieved this unusual example of successful, early de-implementation. Each stakeholder exercised their influence and authority within their respective remits: it is possible that without the actions of each, the final outcome may not have been achieved. Conclusions In Australia, restricting public access to privately operated self-referred full-body CT scans is an oft-cited example of a screening technology that caused harm and which was successfully withdrawn. Within this national context, the case of full-body CT scans suggests that neither single actors nor robust health technology assessments are likely to be sufficient to protect people from the unwanted consequences of too much medicine. These findings are both salient and timely, given growing concerns about overdiagnosis and the emergence of new forms of testing technologies, such as whole genome screening of healthy people. Against a background of technological optimism and commercial opportunism, a commitment to vigilance and cross-sectoral coordination across a range of decision making roles and institutions will be key to efforts to prevent the harms of overdiagnosis.