Adaptation and validation of the oral health literacy instrument for the Chilean population

Objective To report the adaptation and cultural validation of the Oral Health Literacy Instrument (OHLI) for the adult Chilean population attending public and university health services. Study design The original OHLI in English was translated to Spanish and back-translated, then a preliminary version was obtained following review by four experts. A pilot study was carried out in 30 patients, who were asked to assess their understanding of the questionnaire. The following variables were included: sociodemographic factors (sex, age, average monthly income, education and marital status); oral health (history of caries, periodontal disease and oral hygiene); oral health-related quality of life; health literacy; oral health literacy; and psychometric properties (internal consistency, temporal stability, convergent validity and predictive validity). Clinical examination and questionnaire administration were carried out at the public health centres where the participants were receiving treatment. Results A total of 482 persons participated in the study. The internal consistency was high; Cronbach's alpha values were 0.864 for the first section, 0.739 for the second section and 0.887 for the entire instrument. The temporal stability was good, and the intraclass correlation coefficient was >0.6. Regarding convergent validity, the correlation of Chilean version of OHLI (OHLI-cl) with health literacy was positively moderate to strong (r > 0.5 and ρ > 0.5) and statistically significant (P < 0.01). Regarding predictive validity, the correlation of OHLI with oral health damage was negatively weak to moderate (r < −0.2 and ρ < −0.2) and statistically significant (P < 0.01). Conclusion The OHLI-cl demonstrates adequate psychometric properties for measuring the oral health literacy in Chilean populations attending public and university health services.