SUMMARY
This paper addresses the issue of reporting results back in Health and demographic surveillance systems (HDSS). In these particular research platforms, populations are constantly solicited through the longitudinal demographic follow-up and additional surveys. Therefore, reporting results back directly to participants should be considered as a strong ethical requirement. However, like in most health oriented research, results are mostly disseminated among decision makers and local authorities. Therefore, HDSS residents increasingly question the objectives of these studies. Using a participatory approach, 3 days were organized in 2015 to report back findings based on 50 years of research on population, health and environment in the Niakhar HDSS in Senegal. Drawing from the evaluation conducted among a sample of participants to the event, we show that beyond the ethical dimension, such activities may also contribute to change populations’ attitudes to research practices and further influence individuals’ health behaviors at the local level.