Assessment of Pediatric Look-Alike, Sound-Alike Substitution Errors

Medication errors occur frequently in ambulatory prescribing, but little is known about the potential severity of look-alike, sound-alike (LASA) drug substitution errors and their frequency. LASA medication errors occur when a patient receives an incorrect medication because its name is spelled or sounds like another medication. While medication errors have been studied in the pediatric population, the frequency of LASA-specific errors in pediatric prescriptions is not documented or well understood.

This project evaluated the potential severity of specific LASA drug name substitution errors in a pediatric population and estimated the frequencies of potential LASA substitution errors.

The specific aims of this project were to:

• Identify a subset of known LASA drug pairs that are prescribed in ambulatory pediatric care. 
• Estimate frequencies of screening alerts (potential LASA substitution errors) in these drug pairs, and determine the positive predictive values (true positives) of the screening alerts.

A Delphi panel approach was used for the project. Thirty-seven practicing pediatricians evaluated LASA pairs identified in the literature, estimating the harm that might occur should a patient not receive the intended drug in any LASA pair, and the harm that might occur from erroneously receiving the delivered drug. After two rounds of surveys, the Delphi approach assessing harm of drug substitution identified 608 drug pairs of the original list of 1,784 un-duplicated pairs in the literature.

To estimate the frequency of the targeted list of LASA errors, South Carolina Medicaid paid claims data was used to identify patients 0-to-20 years of age who had received both drugs in a LASA pair within a 6-month period, representing a potential LASA substitution error. For 34 percent of the pairs, no patient received a substitution error. For 83 percent of pairs, the cumulative total of subjects who received both drugs amounted to less than one potential LASA error per day in the study population. By contrast, among the remaining 17 percent of pairs, there were 97,163 subjects who received both drugs, amounting to at least 27 potential LASA substitution errors per day.

This project advanced LASA error prevention in pediatric care by developing a prioritized list of LASA drug pairs commonly used in pediatric ambulatory care and considered at high risk to patients should a substitution occur. Such a targeted pediatric list did not previously exist. The data on the risk of harm of the LASA errors combined with the estimates of frequency of pediatric LASA drug substitutions, will allow the development of a prioritized list of high potential harm LASA substitution errors for future prevention efforts. In addition, the work laid the foundation for development of a larger-scale implementation study in pharmacy settings, with the goal of reducing LASA errors.