Modifying Preconceptions about the Safe and Effective Use of Aspirin: Product Label Comprehension as Knowledge Updating

Abstract

Background: Errors in reading label information for nonprescription drugs are often ascribed to poorly written labels or to low health-literacy levels. However, the contribution of drug product preconceptions to these errors has received little attention. This study improves on existing label-comprehension research by assessing label effectiveness in terms of the updating of preconceptions about nonprescription drugs. Method: Ninety undergraduates rated the truth of 35 aspirin claims before and after reading a simulated aspirin label. Some claims were congruent with the Drug Facts; other claims were discrepant from those Drug Facts. Still other claims contained information absent from the Drug Facts. Results: Increases in truth ratings for congruent claims and decreases for discrepant claims were significant, but this knowledge-updating effect is significantly greater for congruent claims. Ratings for absent claims were unchanged. Neither reading care nor verbal ability significantly influenced updating effects. In addition, label inspection was significantly more likely to produce comprehension-beneficial and less likely to produce comprehension-detrimental reversals of initial judgments for congruent claims than was the case for discrepant claims. Conclusions: Literate young adults who carefully read aspirin Drug Facts information are less able to correct aspirin preconceptions refuted by those Facts than to confirm aspirin preconceptions affirmed by those Facts.