Case-control analysis of the financial cost of medication errors in hospitalized patients


The cost of medication errors (MEs), and by extension their impact on the running of hospitals, is generally unknown to hospital managers. This study estimated the financial costs involved in the additional use of hospital resources as a result of MEs. For this we used a database covering 20,014 hospital admissions, with clinical and personal information about each patient, the costs related to his/her stay, and physicians’ prescriptions. Analyses were carried out using cases and control techniques to calculate the additional cost of MEs. During the study period, 2001, the analysis indicated that the MEs analyzed caused an additional 303 days of hospital stay, with an overall annual cost of nearly €76,000. Our study confirms that MEs are a costly reality. The presence of MEs doubled the cost per patient.

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This study was supported by research grant SEC2003-09457/ECO from the Science and Technology Ministry, Madrid, Spain, and by a grant from the University of Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, Spain. The authors acknowledge the comments of the anonymous referees and Dr. Carmen Lacasa on earlier versions of this contribution.

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Correspondence to Jaime Pinilla.

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Pinilla, J., Murillo, C., Carrasco, G. et al. Case-control analysis of the financial cost of medication errors in hospitalized patients. Eur J Health Econ 7, 66–71 (2006).

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  • Medication errors
  • Additional costs
  • Hospitalized patients