Medication errors caused by junior doctors
Authors: James McLay, Sarah Ross
Journal: BMJ (2008)

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 than factors in prescribers, such as burn-out or depression. The mental health of junior doctors has been studied widely, but no data are available on the possible association between depression and burn-out in prescribers and medication errors. In their accompanying cohort study, Fahrenkopf and colleagues report levels of depression and burn-out and associated medication errors in junior doctors working in two paediatric hospitals.6

The use of a paediatric setting is particularly relevant because prescribing in children is complicated by the use of off label drugs and non-standard doses and formulations. Consequently, the risk of error is high—5-27% for each medication order for children admitted to hospital.7

Fahrenkopf and colleagues surveyed 123 junior doctors in two paediatric centres in the US to determine levels of depression and burn-out, and they related the findings to medication errors recorded over a six week period. They found that 20% of junior doctors surveyed met set screening criteria for depression and 74% met the criteria for burn-out; these results agree with previous UK and US studies.8 9 Only depression, however, was associated with a significant (sixfold) increase in medication errors. As sleep deprivation, stress, and burn-out have all been linked to poor performance, the failure to show an association between burn-out and medication error rate is surprising.10 11 In addition, the reported error rate was remarkably low—0.7% per order—half the reported rate for adults and about a 10th of the rate for children.7 However, this may just reflect differences in the definitions, methodologies, and denominators used, which make direct comparisons across studies difficult.12

Although the report by Fahrenkopf and colleagues is interesting and the suggestion that unrecognised depression may be associated with increased medication errors has face validity, the conclusions that can be drawn from this study are limited. The study relies on a small short term survey with a relatively low response rate of 50% and a low number of medication errors. It is therefore highly susceptible to selection bias, as shown by the low medication error rate of 0.7% reported for study participants compared with the overall rate of 1.2% reported for all junior doctors in the participating hospitals. Furthermore, the study cannot determine the direction of any association between depression and medication errors, which is clearly important when designing potential interventions to reduce error rates.

Preventing medication errors and improving patient safety are important goals, which require a better understanding of the complex personal and systems factors involved in generating errors. However, prevention will only be achieved if future studies use standardised methodologies for data collection as well as standardised definitions of medication and prescription errors and a consistent denominator, such as the number of errors for each item prescribed.

Although the suggestion that medication errors may be linked to depression and burn-out seems reasonable, the results reported by Fahrenkopf and colleagues are far from conclusive. Large, prospective, and appropriately designed studies are needed to clarify the roles of individual factors involved in error generation.