The objective of this study was to evaluate the criterion validity of the 14-item Health Literacy Scale (HLS-14) in Brazilian adults and older adults. The cross-sectional study performed in an oral health (OH) prospective cohort was conducted in 2017 in Piracicaba, Brazil. The HLS-14 questionnaire was applied to evaluate Health Literacy (HL) by dimensions: Functional literacy (FunL), Communicative literacy (ComL) and Critical literacy (CriL). An evaluation protocol (EP) was proposed to evaluate the criterion validity of HLS-14 considering HL dimensions (FunL: reading of the drug information leaflets; ComL: reading of the medical prescription and CriL: identification of OH conditions). HL (total) was dichotomized by the median in high (≥35 point) or low (<35 point) HL. Kendall’s rank correlation coefficient (p < 0.05) and chi-squared test (p < 0.05) were applied. There was agreement between EP and HLS-14 for FunL (p < 0.01). There was association between high HL, measured through the HLS-14 questionnaire, assessing the reading of the drug information leaflets (p < 0.01) and the need for help to read them (p < 0.01). EP showed association between high HL and being able to read the drug information leaflet (p < 0.01), not needing help to read (p < 0.01), having found in the prescription all the information to take the medicine (p < 0.01) and knowing two or more health and OH information in the educational material (p < 0.01). The HSL-14 questionnaire showed criterion validity to measure FunL, and for some items of ComL and CriL evaluation. HL evaluation in a practical and multidimensional way could have an effect on the communication between health professional and patient, motivation and health outcomes.

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/pages/standard-publication-reuse-rights)