This systematic review provides strong evidence from many studies to suggest the following implications for policy and practice:

• Social norms interventions¹ targeting health workers are effective in both changing the clinical behaviour of health workers and improving outcomes for patients, and should continue to be implemented (102 studies).
• Credible source (where the target health worker understands that a clinical behaviour has the approval of someone they regard as a credible source) is, on average, effective and should continue to be implemented. It is effective both on its own and as part of a complex intervention (15 studies).
• Social comparison, where a target health worker is provided with information about the clinical behaviour of their peers, allowing them to make a comparison with their own behaviour, is, on average, effective and should continue to be implemented. It is effective both on its own and as part of a complex intervention, and is more effective than simply providing feedback on the target’s behaviour (81 studies). Social comparison can be enhanced by the use of prompts/cues, such as providing lists of patients to support decision-making (such as those who have test results that warrant investigation), or computerised pop-ups when particular codes are entered into an electronic system). The benefit of prompts and cues may not apply when the behaviour is not well understood by the health worker or they need to learn new skills to undertake it (10 studies).

Social norms interventions can be used to good effect across a wide range of health contexts:

• They are effective in changing the behaviour of doctors (68 studies) and other health workers (12 studies).
• They can be used successfully to change a variety of behaviours, such as prescribing (40 studies), ordering and conducting tests (21 studies), managing long-term conditions and improving communication with patients (23 studies).
• They are suitable for use in both increasing behaviour (e.g. more frequent contact with patients or increase in blood testing for a particular condition) (70 studies) or reducing behaviour (e.g. fewer prescriptions for antibiotics or reduction in the number of unwarranted blood tests) (28 studies).
• They can be used successfully in both primary (56 studies) and hospital care (27 studies).

Mode of delivery:

• The source of the intervention can be internal or external.
• Formats including e-mail (9 studies), written (25 studies), web based (8 studies) and mixed (14 studies) have all been used successfully.

¹A social norms intervention seeks to change the clinical behaviour of a target health worker by exposing them to the values, beliefs, attitudes or behaviours of a reference group or person. These social norms interventions can form part of an audit and feedback (A&F) initiative, or may be developed as another behaviour change intervention. These are often interventions with reach: they can be implemented across multiple health workers and settings at low cost, so there is the potential for large absolute gain.

References:

• Tang, M.Y., Rhodes, S., Powell, R. et al. How effective are social norms interventions in changing the clinical behaviours of healthcare workers? A systematic review and meta-analysis. Implementation Science 16, 8 (2021). https://doi.org/10.1186/s13012-020-01072-1
• Cotterill S, Tang MY, Powell R, Howarth E, McGowan L, Roberts J, Brown B, Rhodes S. Social norms interventions to change clinical behaviour in health workers: a systematic review and meta-analysis. Health Services Delivery Res 2020;8(41) https://doi.org/10.3310/hsdr08410