variation in error rates across facilities. The few existing studies of the costs associated with medication errors are limited to the health care costs incurred by preventable injuries, and these are substantial.

At least a quarter of all medication-related injuries are preventable. Many efficacious error prevention strategies are available, especially for hospital care; examples are electronic prescribing and clinical decision-support systems that check dosages and monitor for harmful drug–drug interactions. This report provides guidance on how to implement error prevention strategies in hospitals, long-term care, and ambulatory care.

Establishing and maintaining a strong provider–patient partnership is a key approach for reducing medication errors. The report outlines how such a partnership can be achieved and what roles providers, patients, and third parties must play. For example, consumers should maintain careful records of their medications, providers should review a patient’s list of medications at each encounter and at times of transition between care settings (e.g., hospital to outpatient care), and the federal government should seek ways to improve the quality of pharmacy leaflets and medication-related information on the Internet for consumers.

Health care providers in all settings should seek to create high-reliability organizations that constantly improve the safety and quality of medication use. To this end, they should implement active internal monitoring programs so that progress toward improved medication safety can be accurately demonstrated. The report offers guidance on appropriate monitoring systems for each major care setting.

In carrying out this study, the IOM committee identified enormous gaps in the knowledge base with regard to medication errors. Current methods for generating and communicating information about medications are inadequate and contribute to the incidence of errors. Likewise, incidence rates of medication errors in many care settings, the costs of such errors, and the efficacy of prevention strategies are not well understood. The report proposes a research agenda to address these and other knowledge gaps.