SMS-enabled surveys are gaining traction as a rapid, low-cost means of monitoring food security situations for early warning systems. However, such surveys run the risk of yielding biased results, for instance due to selection, attrition, or non-response bias. To assess the suitability of SMS-enabled surveys for food security monitoring in light of these potential biases, we conducted monthly surveys of 2000 respondents across Uganda for one year. A filtering approach was used to ensure a representative sample. We evaluate the likely accuracy of the data by triangulating the responses with high-frequency data from our own face-to-face household surveys as well as externally collected phone survey data. The analysis suggests that SMS-based surveys can be a promising tool to measure changes in food security status over time but perform less well with regard to measuring the actual food security status. Responses related to the general food situation (rather than dietary diversity, food consumption or market prices) emerged as the most reliable indicator. To investigate implications of selection bias on the results, we use different scenarios with variations in sample composition and size. Even biased samples, e.g. in terms of gender, location or age, show comparable trends, but a minimum sample size is required to obtain accurate results.
Published in Food Security (2026).