Research Activities, November 2010: Safety and Quality of Care: Various factors affect providers' ability to identify spoken drug names

Safety and Quality of Care
Various factors affect providers' ability to identify spoken drug names

A number of drugs have similar sounding names. This can create confusion among health care providers, particularly when using the telephone for medication orders. In a new study, researchers found several factors that can affect how a provider hears, understands, and identifies drug names. These include voice signal-to-background noise ratios, familiarity with the drug name, prescribing frequency, and the similarity of drug names.

A total of 62 pharmacists, 74 family physicians, and 70 nurses were recruited for this study from annual meetings held during 2005. In addition, 43 nonmedical consumers from the general public also participated. The researchers selected 99 brand and 99 generic drug names to be used in the study. These names were then recorded using correct, clinical pronunciation. Participants sat at a computer with headphones. They were asked to repeat back the name of the drug they had heard. These were presented against a background of multitalker noise at three different signal-to-noise conditions. The responses were recorded. In a second step, they went to a different computer where they read aloud all of the drug names from words presented on the screen. They were also asked to rate how familiar they were with each drug name.

The ability of providers to accurately identify spoken drug names increased significantly as the signal-to-noise ratio increased (i.e., as the noise decreased). A provider's subjective familiarity with a name also increased their accuracy in identifying the correct drug name. If a drug was frequently prescribed at the national level, participants were more often able to identify it. In the case of clinicians but not lay people, the existence of similar sounding drug names decreased their ability to accurately identify a particular target drug name.

The researchers recommend that providers receiving telephone orders have the ability to increase the voice signal volume to minimize errors. Using noise-cancelling headphones or being in a quiet area can also help. Other strategies, such as reading back the name, spelling it out, and using both brand and generic names can assist in reducing confusion over spoken drug names. The study was supported in part by the Agency for Healthcare Research and Quality (HS11609).

See "Listen carefully: The risk of error in spoken medication orders," by Bruce L. Lambert, Ph.D., Laura Walsh Dickey, Ph.D., William M. Fisher, Ph.D., and others in the 2010 Social Science & Medicine 79, pp. 1599-1608.

Research Activities, November 2010: Safety and Quality of Care: Various factors affect providers' ability to identify spoken drug names