Can a knowledge calendar improve dietary knowledge? Evidence from a field experiment in rural China

While dietary knowledge significantly impacts food consumption and healthy eating, in many developing countries, the level of dietary knowledge among rural residents is relatively low. An effective and inexpensive intervention is therefore urgently needed to improve dietary knowledge. This study evaluated the effect of an information intervention, in the form of a knowledge calendar, on the dietary knowledge level of rural residents. A propensity score matching with a difference in differences (PSM-DID) approach was applied with two-wave panel data collected from a field experiment to estimate the treatment effect of the information intervention on rural residents' dietary knowledge. The estimation results indicated that the dietary knowledge of rural residents whose households received knowledge calendars significantly increased by 4.7-6.1 % and revealed an active learning effect in rural residents regarding dietary knowledge, suggesting that providing knowledge calendars to rural residents is an effective and low-cost approach for improving their level of dietary knowledge. Additionally, the intervention effect of the knowledge calendar on dietary knowledge was heterogeneous according to individual and household characteristics, such as education, off-farm employment, social network, household income, and farm size. The findings of this study provide an empirical basis for the formulation of inexpensive and effective information intervention policies.