Why do clinicians overtest? A narrative review and workshop group discussion exploring influences on clinician overtesting as possible causes of overdiagnosis

Abstract

Background: Screening and diagnostic tests provide important information to guide clinical management. Overtesting however may cause harm to patients and the healthcare system, including through overdiagnosis. Clinicians are ultimately responsible for test requests, and therefore are ideally positioned to prevent overtesting and overdiagnosis. Through this narrative literature review followed by group discussion at a conference workshop (Preventing Overdiagnosis Conference [PODC], Sydney, 2019), we aimed to identify and categorise factors that influence clinicians to request potentially unnecessary screening and diagnostic tests that could result in overdiagnosis.Methods: Articles exploring factors affecting clinician test ordering behaviour were identified through a systematic search of MedLine in April 2019, forward and backward citation searches and content experts. Two authors screened abstract titles and abstracts, and two authors screened full text for inclusion. Identified factors were categorised into a preliminary framework which was subsequently presented at the PODC for iterative development.Results: The MedLine search yielded 542 articles; 55 were included. Another 10 articles identified by forward-backward citation and content experts were included, resulting in 65 articles in total. Following small group discussion with workshop participants, a revised thematic framework of factors was developed: ● “Interpersonal” – pressure from colleagues and medical culture; pressure from patients and doctor-patient relationship● “Contextual” – clinician knowledge and understanding; cognitive biases and experiences; contemporary medical practice and new technology● “Environmental or workplace” – guidelines, protocols and policies; financial incentives; time constraints, physical vulnerabilities and language barriers; pre-emptive testing to facilitate subsequent care; availability, ownership and ease of access to tests● “Intrapersonal” – fear of malpractice and litigation; intolerance of uncertainty and risk aversion; sense of medical obligation Conclusion: Through this thematic framework, clinicians can become more aware of their test ordering behaviour and feel empowered to limit overtesting and overdiagnosis. This framework may also guide the development of a scale assessing clinician knowledge, attitudes and practices around overtesting and overdiagnosis, to facilitate measurement of the effects of clinician-targeted interventions to prevent overdiagnosis.