Drug Safety

, Volume 29, Issue 11, pp 1011–1022 | Cite as

Clarification of Terminology in Medication Errors

Definitions and Classification
  • Robin E. Ferner
  • Jeffrey K. AronsonEmail author
Leading Article


We have previously described and analysed some terms that are used in drug safety and have proposed definitions. Here we discuss and define terms that are used in the field of medication errors, particularly terms that are sometimes misunderstood or misused. We also discuss the classification of medication errors. A medication error is a failure in the treatment process that leads to, or has the potential to lead to, harm to the patient. Errors can be classified according to whether they are mistakes, slips, or lapses. Mistakes are errors in the planning of an action. They can be knowledge based or rule based. Slips and lapses are errors in carrying out an action — a slip through an erroneous performance and a lapse through an erroneous memory. Classification of medication errors is important because the probabilities of errors of different classes are different, as are the potential remedies.


Medication Error Bosentan Chlorpropamide Wrong Dosage Epoxide Reductase 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



No sources of funding were used to assist in the preparation of this article. The authors have no conflicts of interest that are directly relevant to the content of this article.


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Copyright information

© Adis Data Information BV 2006

Authors and Affiliations

  1. 1.West Midlands Centre for Adverse Drug ReactionsCity HospitalBirminghamUK
  2. 2.Department of Clinical PharmacologyRadcliffe InfirmaryOxfordUK

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