Impact of an audiovisual educational intervention on gastric cancer knowledge and health literacy in a Mexican population.

Abstract

e22533 Background: Gastric Cancer (GC) remains a major global health burden, with rising incidence among individuals under 50 years of age and markedly poor survival when diagnosed at advanced stages. Despite the critical role of prevention and early detection, structured population-level education or screening strategies for GC are lacking in most Latin American countries. Limited health literacy may contribute to low participation in preventive efforts. This study evaluated the impact of a brief audiovisual educational intervention on GC knowledge in a mexican population and explored sociodemographic predictors of baseline knowledge and learning gain. Methods: This is a quasi-experimental pre-post intervention study among adults without prior GC. Participants completed a validated 18-item knowledge questionnaire before and one month after viewing a short education video and an illustrated brochure addressing GC risk factors, symptoms, heredity and prevention. Total scores ranged from 0-18, internal consistency was assessed using Cronbach’s . Changes in global scores were evaluated using Wilcoxon signed-rank test, and item-level changes with McNemar’s test. Multivariable linear regression models identified demographic predictors of pre-post intervention scores, and knowledge gain ( = post-pre). Results: A total of 400 participants completed both assessments. The mean age was 40.5±16.1 years, only 2.5% had undergone a prior endoscopic study. The intervention produced a significant improvement in knowledge, median score increases from 11 to 15; mean gain was 3.27±2.81 points (Z = 16.21, p < 0.001), with a large effect size (r = 0.81). Seventeen of 18 items (94%) demonstrated significant improvement (p < 0.05), particularly in recognition of GC risk factors, hereditary nature, and preventive practices. The questionnaire showed acceptable reliability (α = 0.738 pre; α = 0.656 post). In regression analyses, years of education and place of residence were independently associated with knowledge outcomes. Higher education was associated with greater post-intervention scores (B = 0.19 per year, p < 0.001) and larger knowledge gains (p < 0.001). Residence in peripheral zones was associated with higher baseline knowledge but smaller learning gains. Post-intervention 11 participants referred having an endoscopic screening procedure done. Conclusions: A brief, low-cost audiovisual education intervention significantly improved gastric cancer knowledge in a Mexican population, with large effect size and broad-item impact. Educational attainment emerged as a key modifier of learning, underscoring the importance of tailoring prevention strategies to health literacy levels. Scalable educational interventions may represent an effective equitable approach to strengthen gastric cancer prevention and early detection in regions lacking structured screening programs.