Hospital doctors' attitudes to brief educational messages that aim to modify diagnostic test requests: a qualitative study

Background: Avoidable use of diagnostic tests can both harm patients and increase the cost of healthcare. Nudge-type educational interventions have potential to modify clinician behaviour while respecting clinical autonomy and responsibility, but there is little evidence how this approach may be best used in a healthcare setting. This study aims to explore attitudes of hospital doctors to two nudge-type messages: one concerning potential future cancer risk after receiving a CT scan, another about the financial costs of blood tests.

Methods: We added two brief educational messages to diagnostic test results in a UK hospital for one year. One message on the associated long-term potential cancer risk from ionising radiation imaging to CT scan reports, and a second on the financial costs incurred to common blood test results. We conducted a qualitative study involving telephone interviews with doctors working at the hospital to identify themes explaining their response to the intervention.

Results: Twenty eight doctors were interviewed. Themes showed doctors found the intervention to be highly acceptable, as the group had a high awareness of the need to prevent harm and optimise use of finite resources, and most found the nudge-type approach to be inoffensive and harmless. However, the messages were not seen as personally relevant because doctors felt they were already relatively conservative in their use of tests. Cancer risk was important in decision-making but was not considered to represent new knowledge to doctors. Conversely, financial costs were considered to be novel information that was unimportant in decision-making. Defensive medicine was commonly cited as a barrier to individual behaviour change. The educational cancer risk message on CT scan reports increased doctors' confidence to challenge decisions and explain risks to patients and there were some modifications in clinical practice prompted by the financial cost message.

Conclusion: The nudge-type approach to target avoidable use of tests was acceptable to hospital doctors but there were barriers to behaviour change. There was evidence doctors perceived this cheap and light-touch method can contribute to culture change and form a foundation for more comprehensive educational efforts to modify behaviour in a healthcare environment.