Impact of a health education intervention on knowledge, attitudes, and use of visibility materials among commercial motorcycle riders: a quasi-experimental study in Cameroon

Background Commercial motorcycle riders are among the most vulnerable road users in low- and middle-income countries, with poor visibility contributing significantly to road traffic crashes, particularly under low-light conditions. Visibility materials such as reflective clothing and functional motorcycle lighting systems are effective, low-cost injury prevention measures; however, their use remains suboptimal. This study evaluated the impact of a theory-driven health education intervention on knowledge, attitudes, and use of visibility materials among commercial motorcycle riders in Cameroon. Methods A quasi-experimental, non-randomized controlled before-and-after study was conducted in Limbe (intervention) and Tiko (control) Health Districts. Participants were drawn from a baseline cross-sectional study and followed over an eight-month intervention period. The intervention, guided by the Health Belief Model and developed using the Intervention Mapping framework, combined face-to-face sensitization sessions with mobile phone–based messaging tailored to participants’ literacy levels. Data were collected at baseline and endline using structured questionnaires and direct observation checklists. Knowledge, attitude, and practice scores were treated as continuous variables. Difference-in-differences analysis using generalized estimating equations was employed to estimate the intervention effect, adjusting for socio-demographic factors. Results A total of 249 riders were retained at endline (149 intervention, 100 control). In the intervention group, significant improvements were observed in knowledge (mean difference = 1.75, p < 0.001), attitudes (mean difference = 5.60, p < 0.001), and practices (mean difference = 0.36, p = 0.012), while no significant changes were observed in the control group. Difference-in-differences analysis showed that the intervention was associated with significant increases in knowledge (β = 1.68, 95% CI: 1.16–2.20) and attitudes (β = 5.51, 95% CI: 4.22–6.80), but not practices (β = 0.34, 95% CI: −0.11–0.79). For visibility material use, the intervention was associated with a significant increase in reflective jacket use (AOR = 4.34, 95% CI: 1.88–10.02), while no significant effects were observed for other visibility materials. Conclusion A theory-informed health education intervention significantly improved knowledge, attitudes, and reflective jacket use among commercial motorcycle riders. However, improvements in other visibility-related practices were limited, suggesting that educational strategies alone may be insufficient to address structural and resource-related barriers. Multi-level interventions combining education with improved access and enforcement are needed to achieve sustained adoption of visibility materials for injury prevention. Trial registration ClinicalTrials.gov Identifier: NCT07087444. Registered on July 28, 2025.