With community eligibility, what data source will replace the free / reduced price rate?

U.S. school children with household incomes below 130% of the federal poverty guideline have long been eligible for free school lunch and breakfast, while those with slightly higher income but still below 185% of the poverty guideline are eligible for reduced-price lunch. With a new community eligibility provision, some districts will provide free lunches to all children.

The most important thing to know about this policy is that it may feed more children.

This blog post is about a less important secondary question that nonetheless has some potential interest for readers in U.S. food policy: "What new source of data will replace the free / reduced price rate as a proxy variable for local poverty?" In the past, the percentage of children who received free and reduced price meals served to indicate the level of local poverty -- a higher percentage meant the neighborhood is comparatively poor.

At FiveThirtyEight, Ben Wieder explains the many policy and research uses for this proxy poverty measure:

Two analyses (.pdf) found that school lunch data has been used in about 1 in 5 studies looking at academic achievement conducted by education researchers; that doesn’t take into account its role in work by psychologists, sociologists, economists and researchers in a host of other disciplines.

The data has been used in studies looking at best teaching practices, school discipline and whether playing an instrument improves academic performance. It was a measure of poverty for a study on why kids start smoking, used to differentiate swimming ability among minority students, and a measure of socioeconomic status in at least one article in the Journal of Happiness Studies.

Who gets to participate in the program can have policy implications as well.

Matt Cohen, chief research officer at the Ohio Department of Education, is chairing a working group organized by the National Center for Education Statistics (NCES) to find alternatives to participation in the school lunch program for measuring students’ socioeconomic status.

I agree with some of the sources quoted in the article, who point out that this never was all that great a proxy for poverty in the first place. For example, consider a study seeking to measure whether childhood food insecurity is higher in high-poverty neighborhoods. The free / reduced price proxy variable is a poor indicator for neighborhood poverty, because the meals themselves may directly help reduce childhood food insecurity. Still, it will take some new effort to find a replacement variable, and some research and policy purposes will be inconvenienced in the interim period.