BACKGROUND In the past 10 years, medication errors have come to be recognised as an important cause of iatrogenic disease in hospital patients.

AIMS To determine the incidence and type of medication errors in a large UK paediatric hospital over a five year period, and to ascertain whether any error prevention programmes had influenced error occurrence.

RESULTS Medication errors occurred in 0.15% of admissions (195 errors; one per 662 admissions). While the highest rate occurred in neonatal intensive care (0.98%), most errors occurred in medical wards. Nurses were responsible for most reported errors (59%). Errors involving the intravenous route were commonest (56%), with antibiotics being the most frequent drug involved (44%). Fifteen (8%) involved a tenfold medication error. Although 18 (9.2%) required active patient intervention, 96% of errors were classified as minor at the time of reporting. Forty eight per cent of parents were not told an error had occurred. The introduction of a policy of double checking all drugs dispensed by pharmacy staff led to a reduction in errors from 9.8 to 6 per year. Changing the error reporting form to make it less punitive increased the error reporting rate from 32.7 to 38 per year.

CONCLUSION The overall medication error rate was low. Despite this there are clear opportunities to make system changes to reduce error rates further.