Effect of digital behavior change intervention on malaria prevention practices in selected local government areas in Lagos State, Nigeria

Abstract Background Malaria remains a major public health burden in Nigeria despite expanding digital technology access. Evidence on the effectiveness of Digital Behavior Change Interventions (DBCIs) in improving malaria prevention at the community level remains limited. This study examined the effect of a theory-driven DBCI on malaria knowledge, risk perception, and preventive practices among adults in Lagos State. Methods A quasi-experimental study was conducted with 219 adults recruited from Primary Healthcare Centres in Alimosho (intervention) and Oshodi-Isolo (control) Local Government Areas. The six-week DBCI, grounded in the Health Belief Model, was delivered via WhatsApp broadcasts, automated SMS, and weekly interactive webinars. Outcomes were assessed at baseline, post-intervention, and at a 10-week follow-up using repeated measures ANOVA with Greenhouse-Geisser correction and Bonferroni-adjusted pairwise comparisons. Results Significant improvements were observed across all outcomes in the intervention group. Malaria knowledge scores rose from 10.20 (SD = 5.08) at baseline to 16.09 (SD = 1.36) at follow-up (F(1.066, 116.235) = 107.631, p < .001, partial η² = .497). Risk perception scores increased from 72.16 (SD = 13.31) to 90.59 (SD = 3.41) (F(1.302, 141.971) = 150.858, p < .001, partial η² = .581), and preventive practice scores improved from 19.62 (SD = 6.60) to 25.52 (SD = 2.78) (F(1.104, 120.340) = 63.696, p < .001, partial η² = .369). All outcomes continued improving beyond the immediate post-intervention period, indicating sustained effects. Conclusion A theory-driven DBCI delivered via WhatsApp and SMS produced large, sustained improvements in malaria knowledge, risk perception, and preventive practices among urban adults in Lagos State. These findings support integrating mobile health strategies into routine malaria control programmes in Nigeria and across sub-Saharan Africa.