How Behavioural Economics Can Reduce Antibiotic Over-Prescription

GPs already know that unnecessary antibiotics fuel resistance, yet over-prescription persists. Behavioural economics can reduce antibiotic over-prescription by making each GP’s prescribing visible and comparable: in Australia, peer-comparison letters cut scripts among high prescribers by 12.3% in six months – without a new clinical guideline. This article explains why GPs over-prescribe, how peer comparison works, the evidence, and four steps for Asia-Pacific health systems. 

Key takeaways 

• Many GPs assumed their prescribing was similar to their colleagues’ – peer comparison showed it wasn’t. 

• Peer-comparison letters cut scripts by 12.3% among Australia’s top 30% of prescribers. 

• The nudge works wherever routine prescribing data exists, without new legislation or funding. 

What Is Antibiotic Over-Prescription, and Why Does It Matter? 

Antibiotic over-prescription is prescribing antibiotics when they aren’t needed – and every unnecessary script speeds the rise of ‘superbugs’ and shortens the working life of the antibiotics we rely on. In 2024, 37.1% of Australians – more than ten million people – had at least one antimicrobial dispensed under the community pharmaceutical benefits scheme, and a meaningful share is thought to be unnecessary.¹ 

Why Do GPs Over-Prescribe Antibiotics? 

The barrier isn’t information, it’s behaviour. GPs had long known the risks of overprescribing, but many assumed their own habits were much the same as their colleagues’. That is why simply telling GPs to prescribe less rarely works. 

How Does Peer Comparison Change Prescribing Behaviour? 

Peer comparison works through social comparison: showing GPs how their scripts stack up against similar colleagues challenges the norms around prescribing. Central to Australia’s campaign were letters comparing GPs with their peers, an approach often linked to the Hawthorne Effect – people behave differently when they feel observed.² Three things make it work: 

• It makes the invisible visible: a GP can’t act on a gap they never see, and many realised their ‘normal’ prescribing wasn’t normal at all. 

• It taps into professional identity: prescribing more than similar GPs challenges how you see yourself as a careful practitioner. 

• It uses loss aversion: being a high outlier troubles GPs more than praise for being average motivates them. Learn more about loss aversion. 

Does It Work? Evidence From Australia and the UK 

Yes. Peer-reviewed data and a controlled trial both show meaningful reductions. 

Case 1: NPS MedicineWise programmes (Australia) 

• Result: since 2009, an average of 126,536 fewer antibiotics dispensed each month – a 14% reduction; after a more intensive push from 2012, close to a 20% reduction against forecast by June 2015.⁴ 

• Limitation: national dispensing data can’t separate the effect of each campaign component. 

Case 2: Peer-comparison letters (Australian Government Behavioural Economics Team) 

• Context and intervention: the top 30% of prescribers received a letter with a graph comparing them to peers. 

• Result: a 12.3% cut in scripts over six months – more than three times the effect of educational material alone.² 

• Lesson for practice: comparison beats education. 

Case 3: The UK trial 

• Result: a comparable UK trial achieved a smaller but meaningful 3.3% reduction.³ The approach transfers, though effect sizes vary. 

How Can Health Systems in Asia-Pacific Apply This Approach? 

Any health authority or payer with large GP or pharmacist networks and routine prescribing data can use the same low-cost nudge. Antimicrobial resistance is a defining public health challenge across Asia-Pacific, which is why the WHO featured Australia’s letters as a global case study.³ Australia’s own consumption – 23.5 defined daily doses per 1,000 population, against an OECD average of 20.6 – shows room to improve even in a well-resourced system. In Japan, a monthly peer-comparison newsletter also cut unnecessary antibiotic prescriptions – see how behavioural science helps reduce doctors’ over-testing. 

4 Steps to Reduce Over-Prescription With Behavioural Economics 

1. Start with prescribing data to identify the highest prescribers. 

2. Build a fair comparison with similar peers in the same area. 

3. Send a personalised letter or report with a simple graph, framed around being a high outlier. 

4. Measure and repeat against a control group or forecast so the change lasts. 

Common Mistakes and Limitations

• Relying on facts alone: information without comparison rarely changes behaviour. 

• Expecting identical results everywhere: 3.3% in the UK versus 12.3% in Australia. 

• Not measuring: without a control group, it’s hard to tell what worked. Related reading: Choosing Wisely. 

Frequently Asked Questions 

Frequently Asked Questions 

How does behavioural economics reduce antibiotic over-prescription? 

By making each GP’s prescribing visible and comparable with peers, which changes behaviour more than education alone. 

Why do GPs over-prescribe antibiotics? 

Many know the risks but assume their prescribing is similar to colleagues’ – without the comparison, they see no reason to change. 

Can this approach work in Asia-Pacific? 

Yes – wherever routine prescribing data and large GP or pharmacist networks exist. 

Next Steps: Turn Prescribing Data Into Behaviour Change 

Australia’s campaign shows GP behaviour is malleable: increasing the visibility of prescribing was enough for GPs to question their practice. As a programme manager, move from facts towards emotion, and ask how to make the objective more emotionally tangible, behaviour more transparent and social, and the desired behaviour the simplest option. 

Want to design a peer-comparison programme for your health system? Get in touch with DeltaMV’s Healthcare Behavioural Strategy team. 

Sources 

1. Australian Centre for Disease Control. (2026). Sixth Australian report on antimicrobial use and resistance in human health (AURA report). https://www.amr.gov.au/sites/default/files/2026-02/sixth-australian-report-on-antimicrobial-use-and-resistance-in-human-health-aura-report_0.pdf 

2. Medical Republic. (2018, July 4). Nudge tactics spark drop in antibiotic scripts. https://www.medicalrepublic.com.au/nudge-tactics-spark-drop-antibiotic-scripts/1953 

3. World Health Organization. (2018). Nudge vs superbugs – features from around the world. https://www.who.int/campaigns/world-amr-awareness-week/2018/features-from-around-the-world/nudge-vs-superbugs 

4. Wu, J., Taylor, D., Ovchinikova, L., Heaney, A., Morgan, T., Dartnell, J., Holbrook, R., Humphreys, L., Weekes, L., & Blogg, S. (2018). Relationship between antimicrobial-resistance programs and antibiotic dispensing for upper respiratory tract infection: An analysis of Australian data between 2004 and 2015. Journal of International Medical Research, 46(4), 1326–1338. https://doi.org/10.1177/0300060517740813