Health literacy and prenatal screening acceptability for hemoglobinopathies in Tunisia: a pilot mediation study

Hemoglobinopathies remain a major public health concern in Tunisia. Effective prevention depends on informed prenatal screening, yet the role of health literacy in screening acceptability is poorly documented in North Africa. This pilot study developed and culturally adapted a 9-item health literacy questionnaire based on Nutbeam's multidimensional framework and examined its direct and indirect associations, via perceived understanding, with screening acceptability. A cross-sectional pilot study was conducted at the national referral maternity center CHU La Rabta in Tunis with 256 pregnant women aged 18-49 years. The questionnaire was rigorously adapted to Tunisian Arabic dialect through forward-back translation and cognitive debriefing with five pregnant women. Health literacy was assessed using functional, interactive, and critical subscales (1-4 Likert scale). Screening acceptability and perceived understanding to decide were also measured. Data was analyzed with descriptive statistics, reliability testing (Cronbach's α), Spearman correlations, and bootstrapped mediation analysis. Mean global health literacy was 2.70 ± 0.77 (59.8% in the "high" category). The 9-item scale showed good reliability (Cronbach's α = 0.826). Interactive literacy scored highest (2.95 ± 0.92), while functional (2.58 ± 0.93) and critical (2.56 ± 1.00) dimensions were lower. The analysis revealed associations consistent with partial mediation: higher health literacy was associated with screening acceptability both directly (c' = 0.438, p = 0.042) and indirectly through perceived understanding (indirect effect = 0.314, 95% CI 0.128-0.562, p < 0.001), accounting for 41.8% of the total effect. After adjustment for age, education, and residence, global health literacy remained independently associated with screening acceptability (adjusted OR = 1.55, p = 0.041). A brief, culturally adapted health literacy tool proved feasible and reliable in the Tunisian prenatal context. Higher health literacy was associated with greater screening acceptability both directly and indirectly through improved perceived understanding. These findings provide a strong empirical basis for integrating health literacy assessment and targeted literacy-enhancing interventions into Tunisia's national hemoglobinopathy prevention program.