Psychometric properties of BREALD-30 for assessing adolescents’ oral health literacy

OBJECTIVE: To evaluate the psychometric properties of the Brazilian Portuguese version of the Rapid Estimate of Adult Literacy in Dentistry (BREALD-30) administered to adolescents. METHODS: The study included 750 adolescents: 375 aged 12 years and 375 aged 15–19 years, attending public and private schools in Campina Grande, state of Paraíba, Brazil, in 2017. Reliability was measured based on internal consistency and test-retest reliability. Convergent validity was measured based on correlations between BREALD-30 and Functional Literacy Indicator scores. Divergent validity was measured by comparing BREALD-30 scores with sociodemographic variables. For predictive validity, the association between BREALD-30 scores and the presence of cavitated carious lesions was tested using a multiple logistic regression model. All statistical tests were performed with a significance level of 5%. RESULTS: BREALD-30 showed good internal consistency for the 12 year olds and 15 to19 year olds (Cronbach’s alpha = 0.871 and 0.834, respectively) and good test-retest reliability [intraclass correlation coefficient (ICC) = 0.898 and 0.974; kappa = 0.804 and 0.808, respectively]. Moreover, item-total correlation was satisfactory for all items. BREALD-30 had convergent validity with the Functional Literacy Indicator for 12 year olds (rs = 0.558, p < 0.001) and for 15 to 19 year olds (rs = 0.652, p < 0.001). Participants with higher oral health literacy levels who attended private schools (p < 0.001), belonged to economic classes A and B2 (p < 0.001), and who had parents with higher education levels (p < 0.001) were included, indicating the divergent validity of the BREALD-30. Participants with lower BREALD-30 scores were more likely to have cavitated carious lesions [12 year olds: odds ratio (OR) = 2.37; 95% confidence interval (95%CI): 1.48–3.80; 15 to 19 year olds: OR = 1.96; 95%CI 1.24–3.11]. CONCLUSIONS: BREALD-30 shows satisfactory psychometric properties for use on Brazilian adolescents and can be applied as a fast, simple, and reliable measure of oral health literacy.