Nutrition-label comprehension before and after a brief online educational session: a mixed-effects analysis in an adult sample

Purpose This study aims to examine nutrition-label comprehension immediately before and after a one-hour online educational session, compare baseline comprehension across two product-label conditions and assess whether pre-post patterns differed by gender. Design/methodology/approach This one-group pre-post study included 196 adults. The same two products and nutrition facts panels (NFPs) were used at both assessments; a traffic-light overlay was added or removed in a fixed sequence, so each product was assessed once with and once without traffic-light information. A 12-item criterion-referenced score was analyzed using a linear mixed-effects model. Findings Baseline comprehension was higher for the tomato-paste/traffic-light condition than the chicken-strips/NFPs condition (4.04 versus 2.69; p < 0.001). Total scores were higher immediately after the session (8.76 versus 6.70). Adjusted pre-post differences were 2.53 points among males [95% confidence intervals (CI) 2.15–2.92] and 1.73 among females (95% CI 1.41–2.05); the difference in change was 0.80 (95% CI 0.30–1.30; p = 0.002). Research limitations/implications The design lacked a concurrent comparison group and used immediate follow-up, two products with different nutrient profiles, a fixed assessment sequence and online convenience recruitment; unmatched post-session records may also have introduced selection bias. Practical implications A standardized online session can incorporate immediate comprehension assessment in community awareness activities. Controlled studies are needed to establish effectiveness, retention and behavioral outcomes. Originality/value The study provides criterion-referenced evidence from an understudied adult sample using matched assessments and gender-specific contrasts.