Background: Improvements in healthcare have led conversely to overtreatment and overdiagnosis. Quaternary prevention is defined as an action taken to identify patients at risk of overmedicalisation, to protect them from new medical invasion, and to suggest alternative, acceptable care. Point-of-care tools, such as BMJ Best Practice and Practical Approach to Care Kit (PACK), are ideally placed to educate, support clinical decision making and help practitioners to rapidly identify the medical issues related to overdiagnosis or overtreatment during the routine course of care. In this way point-of-care tools could help rationalise what care, investigation and treatment is given.

Methods: Selected issues associated with overuse of care were identified in BMJ Best Practice, a point-of-care web- and mobile-based tool for use by healthcare professionals. These were then assessed to review Best Practice's existing approach to quaternary prevention and a possible future strategy to highlight relevant aspects and aid in averting overuse of care. The selected issues were:
- Routine screening tests for people at average risk: prostate-specific antigen (PSA) for prostate cancer in the absence of shared decision making;
- Diagnosis: imaging for nonspecific, low-back pain without red flags; and,
- Treatment: antibiotics for suspected uncomplicated acute otitis media.

Results: The risks and benefits associated with the selected issues were all well-described in BMJ Best Practice in applicable subsections. New features such as the incorporation of Cochrane Clinical Answers and BMJ Rapid Recommendations allow for rapid assessment of the evidence base at the point of care, promoting informed and shared decisions. Delivering this in more visual ways has the potential to improve uptake but needs further testing.

Conclusions: Web and mobile decision-support applications can raise awareness of overdiagnosis and overtreatment during the course of the clinical workflow. Examples of areas where this may be helpful include selected screening tests for people at average risk, and selected treatments for people with uncomplicated or chronic conditions.