Data quality is always going to be an issue. In this case the reporting is based on an honor system. I imagine extrapolation using satellite imagery and mathematics on people mobility would be good for validation and correlation.

Sat imagery, understanding average household size, knowing average calorie consumption vs what can be grown on the ground, knowing imports of particular products, etc.

For example you couldn't use the same algorithm that you would on US or Japan as you would on a non-developed/developing country, you'd get nonsensical numbers.