An acetaminophen icon helps reduce medication decision errors in an experimental setting



      To assess the effect of adding an acetaminophen ingredient icon to acetaminophen medication labels on consumer decision making about concomitant use of acetaminophen medications to avoid overdose, which is associated with liver injury.


      Parallel-group randomized study.


      Consumer research facilities in Indianapolis, Baltimore, and Los Angeles.


      A total of 517 adults (30% with limited health literacy) recruited at 3 consumer research sites.


      Participants were randomized to a non-icon condition in which medications carried current labeling or an icon condition in which all acetaminophen medications were additionally marked with an icon.

      Main outcome measures

      Participants were presented with a medicine cabinet containing 12 diverse prescription and non-prescription medications, one-half containing acetaminophen, and made decisions about which medications were appropriate to take after an acetaminophen medication had already been taken. Outcome measures were errors in medication decisions and response time.


      The icon reduced the odds of participants making medication-decision errors by 53% (CI 31%-68%), with effects evident across medication categories. The icon eliminated a trend for those with lower health literacy or less education to have a greater likelihood of making errors. The icon also reduced response times, indicating reduced cognitive load for decisions.


      An icon can improve decision making regarding acetaminophen-containing medications, particularly among individuals with limited health literacy or education.
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      Saul Shiffman, PhD, Pinney Associates and University of Pittsburgh, Pittsburgh, PA


      Helene Cotton, MBA, Independent research consultant, Chicago, IL


      Christina Jessurun, PharmD, McNeil Consumer Healthcare, Skillman, NJ


      Jeffrey M Rohay, PhD, Pinney Associates and University of Pittsburgh, Pittsburgh, PA


      Mark A Sembower, MS, Pinney Associates, Pittsburgh, PA