Table 1.
Datasets used in state- and county-level comparisons.
| Source | Update frequency | Unit of measurement | Measure of onsite schooling | Dates | Data collection | Question | Sample size | Weighting |
|---|---|---|---|---|---|---|---|---|
| Delphi U.S. CTISa | Daily | Household | If children in household with children in 1st–12th grade are attending any onsite instruction | 12/1/20–5/31/21 (excluding 12/23/20–1/2/21) | Facebook platform-based survey | Do any of the following apply to any children
in your household (pre-K-grade 12)? Going to in-person classes full-time; Going to in-person classes part-time |
1,277,837 respondents from all states and FIPS codes | Facebook weights |
| Burbiob | Weekly | County | Percentage of county offering onsite instruction | Weeks of 12/4/20–5/28/21 (excluding last two weeks in December) | Searches Internet for information on 1,200 districts; aggregates them to the county level, imputing for smaller counties | Percentage of county offering: only virtual, combination, or traditional in-person schooling | All counties | County population |
| U.S. School Closure and Distance Learning Databasec | Monthly | School | Percentage of schools open for onsite instruction | Months of December 2020 - May 2021 | SafeGraph GPS data on 80,785 public schools in the country | Decline in total visits to school compared to
the same month in 2019 At least 50% decline → “closed” Report the percentage of schools in the county that are closed |
80,785 public schools | District enrollment (for state-level comparisons) |
Note: Overall comparison is on the monthly percentage of any in-person schooling in the state/county; All three sources cover nearly every United States county and cover all U.S. states.