Patients' literacy skills: more than just reading ability.

Limited literacy contributes to suboptimal care and outcomes for patients. The Institute of Medicine noted that future work in health literacy should consider multiple literacy skills. However, lacking empirical evidence of the relationship between different literacy skills, reading skills are often used as proxies of literacy in research and practice. Using a community-based sample of 618 individuals residing in Boston, Massachusetts, and Providence, Rhode Island, the authors conducted a principal component analysis on measures of four literacy skills--reading, numeracy, oral (speaking), and aural (listening)--to examine whether and to what extent literacy can, or should, be represented by a single measure. The first principal component represented overall literacy and could only explain 60% of the total variation in literacy skills among individuals. The second principal component differentiated between numeracy/reading and the oral/aural exchange. While reading and numeracy best represent overall literacy, patients' relative strengths may vary. Those with moderate reading ability may have high oral and aural language skills. Conversely, people who have difficulties speaking with or understanding a provider may read well. Effective communication with patients should rely on the oral exchange and written health information, and not rely on a single literacy skill.