RESUMO
BACKGROUND: Many studies have shown that low health literacy (HL) is associated with several adverse outcomes. In this study, we systematically reviewed the prevalence of low HL in Europe. METHODS: PubMed, Embase, and Scopus were searched. Cross-sectional studies conducted in the European Union (EU), published from 2000, investigating the prevalence of low HL in adults using a reliable tool, were included. Quality was assessed with the Newcastle-Ottawa Scale. Inverse-variance random effects methods were used to produce pooled prevalence estimates. A meta-regression analysis was performed to assess the association between low HL and the characteristics of the studies. RESULTS: The pooled prevalence of low HL ranged from of 27% (95% CI: 18-38%) to 48% (95% CI: 41-55%), depending on the literacy assessment method applied. Southern, Western, and Eastern EU countries had lower HL compared to northern Europe (ß: 0.87, 95% CI: 0.40-1.35; ß: 0.59, 95% CI: 0.25-0.93; and ß: 0.72, 95% CI: 0.06-1.37, respectively). The assessment method significantly influenced the pooled estimate: compared to word recognition items, using self-reported comprehensions items (ß: 0.61, 95% CI: 0.15-1.08), reading or numeracy comprehensions items (ß: 0.77, 95% CI: 0.24-1.31), or a mixed method (ß: 0.66, 95% CI: 0.01-1.33) found higher rates of low HL. Refugees had the lowest HL (ß: 1.59, 95% CI: 0.26-2.92). Finally, lower quality studies reported higher rates of low HL (ß: 0.56, 95% CI: 0.06-1.07). DISCUSSION: We found that low HL is a public health challenge throughout Europe, where one in every three to almost one in every two Europeans may not be able to understand essential health-related material. Additional research is needed to investigate the underlying causes and to develop remedies. PROSPERO REGISTRATION: CRD42019133377.