Antimicrobial resistance

  • 2019

Antimicrobial resistance is a growing issue in New Zealand. Overprescription of antibiotics drives this growth. However, at the same time, Māori and Pacific Islands patients are often underprescribed antibiotics.


Two behavioural insights may be effective at changing doctors’ prescribing  behaviour:

  • Social norms. We are influenced by the actual or perceived behaviours of those around us and tend to behave the way we think most other people do.
  • Messenger effect. People give different weights to information depending on who is communicating that information.

Doctors have few ways of knowing whether their prescribing rate is ’normal.’ Highlighting an individual’s difference from everyone else can encourage them to reassess their habits.


We ran a trial to test a behaviourally designed letter that reminded doctors of the threat of antimicrobial resistance and compared their prescription rate to that of their peers.

Result & Impact

The intervention successfully reduced antibiotic prescribing in the general population but we avoided a detrimental impact on prescriptions to Māori and Pacific Islands patients.