Article Text

Download PDFPDF
Prescribing errors in hospital inpatients: their incidence and clinical significance
  1. B Dean1,
  2. M Schachter2,
  3. C Vincent3,
  4. N Barber4
  1. 1Research Pharmacist, Department of Practice and Policy, The School of Pharmacy, University of London, London WC1N 1AX, UK
  2. 2Senior Lecturer and Honorary Consultant Physician, Clinical Pharmacology, Imperial College School of Medicine, London, UK
  3. 3Professor of Psychology, Clinical Risk Unit, University College London, London WC1E 6BT, UK
  4. 4Professor of the Practice of Pharmacy, Department of Practice and Policy, The School of Pharmacy, University of London, London WC1N 1AX, UK
  1. Correspondence to:
    Dr B Dean, Director, Academic Pharmacy Unit, Pharmacy Department, Hammersmith Hospitals NHS Trust, London W12 0HS, UK;


Background: It has been estimated that 1–2% of US inpatients are harmed by medication errors, the majority of which are errors in prescribing. The UK Department of Health has recommended that serious errors in the use of prescribed drugs should be reduced by 40% by 2005; however, little is known about the current incidence of prescribing errors in the UK. This pilot study sought to investigate their incidence in one UK hospital.

Methods: Pharmacists prospectively recorded details of all prescribing errors identified in non-obstetric inpatients during a 4 week period. The number of medication orders written was estimated from a 1 in 5 sample of inpatients. Potential clinical significance was assessed by a pharmacist and a clinical pharmacologist.

Results: About 36 200 medication orders were written during the study period, and a prescribing error was identified in 1.5% (95% confidence interval (CI) 1.4 to 1.6). A potentially serious error occurred in 0.4% (95% CI 0.3 to 0.5). Most of the errors (54%) were associated with choice of dose. Error rates were significantly different for different stages of patient stay (p<0.0001) with a higher error rate for medication orders written during the inpatient stay than for those written on admission or discharge. While the majority of all errors (61%) originated in medication order writing, most serious errors (58%) originated in the prescribing decision.

Conclusions: There were about 135 prescribing errors identified each week, of which 34 were potentially serious. Knowing where and when errors are most likely to occur will be helpful in designing initiatives to reduce them. The methods developed could be used to evaluate such initiatives.

  • medication errors
  • prescribing errors

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Linked Articles

  • Action points
    Tim Albert