The Portuguese adaptation of the HLS19-Q47: insights into health literacy levels and public health implications

Background: Health literacy (HL) relates to the knowledge, motivation and skills necessary to make informed decisions on health care, disease prevention and health promotion. It is an important social determinant of healthrelated behaviours and health outcomes, being considered as a modifiable risk factor in public health. Levels of HL vary greatly across Europe, which raises the need for a systematic assessment to guide interventions and policies. Method: This study aimed to adapt the Health Literacy Survey (HLS19-Q47), developed by the M-POHL - WHO Action Network on Measuring Population and Organizational Health Literacy, to the Portuguese context. A representative sample comprising 1,027 valid cases was collected following CATI methodology. The survey included the HLS19-Q47 and the optional packages on Communicative HL and Costs and Health Economics. Results: Results supported the adequacy of this measure. Reliability assessment based on Cronbach’s alpha showed satisfactory internal consistency across HL dimensions (α = 0.85–0.89), and general HL score α = 0.94. Construct validity was evidenced through associations between HL and known predictors of HL (education, socioeconomic status), and positive correlations with Communicative HL. General HL was scored as M = 59 (SD = 10) while Communicative HL scored M = 65 (SD = 14) indicating higher scores on Communicative HL than with General HL in the Portuguese population. Results related to health economics suggested a significant economic burden due to health-related issues. Conclusions: The present study supported the reliability and validity of the adapted version HLS19-Q47 in Portugal, while laying the ground for monitoring of HL levels and development of strategies to tackle HL disparities. Increased HL can contribute to the sustainability of the national health system by promoting positive health behaviours, leading to better public health outcomes.