The effects of medical errors on patient morbidity and mortality have been highlighted in the United Kingdom and the United States.1 2Preventable medication errors account for 10-20% of adverse events in patients admitted to hospital.1 In the UK, up to 1.5% of hospital prescriptions may contain a medication error, and a quarter of these could result in potentially serious effects.3 The situation is similar in Australia and the US—medication errors occur in about 1-2% of patients admitted to hospital, resulting in around 7000 deaths a year in the US alone.2 4

Although junior doctors are responsible for most medication errors in hospital,5 investigations to date have mainly focused on the role of system failures, rather …