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New study on computerized order entry finds flaws that could lead to errors, but there are opportunities for improvement

Although computerized physician order entry (CPOE) is expected to significantly reduce medication errors, systems must be implemented thoughtfully to avoid facilitating certain types of errors, according to a recent study supported by the Agency for Healthcare Research and Quality (HS11530). For the study, researchers examined clinicians' experience in using one CPOE system at a major urban teaching hospital.

According to AHRQ Director Carolyn M. Clancy, M.D., the findings are typical for products early in their implementation, and new health care information technology products usually go through an ongoing process of refinement and improvement as health care workers identify problems. Ideally, principles of human factors research, usability testing, and workflow impact should all be considered before products are released into the workplace.

The researchers identified 22 situations in which the CPOE system increased the probability of medication errors. According to the researchers, these situations fell into two categories: information errors generated by fragmentation of data and hospitals' many information systems and interface problems between humans and machines, where the computers' requirements are different than the way clinical work is organized.

Some of the flaws identified by the study include:

  • Medical staff may look to the CPOE system to determine minimal effective or usual dosage for infrequently used medications. However, the CPOE system may only reflect dosage sizes available at the pharmacy, which may differ from the minimal or usual dosage that should be prescribed. The flaw represents an inappropriate use of the data available on the CPOE system and could result in prescribing an incorrect dosage.
  • Clinicians could select the wrong patient file because names and drugs can be hard to read, and patients' names do not appear on all screens.
  • A patient's medication information is seldom synthesized on a single screen. Up to 20 screens might be needed to see all of a patient's medications, increasing the likelihood of selecting a wrong medication.
  • Because of patient load and multiple tasks, nurses are often unable to enter timely information on the computer about the administration of drugs. The delayed information may affect later medication and clinical decisions.
  • Computer downtime, whether for maintenance or in the event of "crashes," can result in delays in medications reaching patients.

The study was led by Ross Koppel, Ph.D., of the University of Pennsylvania. It is based on interviews with medical staff, focus groups, shadowing staff as they worked, and a survey of interns and residents at a major urban teaching hospital with a widely used CPOE system.

Although these findings are important, Dr. Clancy notes that the study focuses on the experience of one hospital and one product and may not be easily applied to industry at large. It means these products are in their early implementation period, and there will be a learning period to both improve these systems and make CPOE function at its best. Implementation problems would be minimized through testing before products are marketed and through adaptation to meet the needs of individual clinical settings.

For more information, see "Role of computerized physician order entry systems in facilitating medication errors," by Dr. Koppel, Joshua P. Metlay, M.D., Ph.D., Abigail Cohen, Ph.D., and others, in the March 9, 2005, Journal of the American Medical Association 293(10), pp. 1197-1203.

Editor's Note: AHRQ is funding more than $139 million in grants and contracts nationwide over 3 years to support planning, implementation, and evaluation of health information technologies, including CPOE. AHRQ is also funding studies of how information technologies affect clinical workflow. AHRQ-supported projects assess the benefits and also identify any problems in using health information technology.

In addition, AHRQ is working with an organization of leading employers who are major health benefits purchasers, the Leapfrog Group, to develop an evaluation tool to assess the effectiveness of CPOE and electronic prescribing in reducing medical errors. The development of this evaluation tool is being supported to encourage and enable ongoing evaluation of CPOE and other information technologies as they are considered for incorporation into clinical settings to improve the quality of health care.

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