Knowledge on effective strategies to encourage participation in epidemiological web-based research is scant. We studied the effects of reminders on overall participation. 3,876 employees were e-mailed. The results showed that reminders significantly increased participation. This study contributes to the understanding of how to improve participation in web-based research. The findings have implications for the design of future studies and the development of effective strategies to encourage participation. The study highlights the importance of reminders in web-based research and provides insights into the factors that influence participation. The results of this study can be used to inform the development of more effective web-based research tools and strategies.