diff --git a/docs/api/covidcast-signals/nssp.md b/docs/api/covidcast-signals/nssp.md index 3f69a7cd0..2501d55a4 100644 --- a/docs/api/covidcast-signals/nssp.md +++ b/docs/api/covidcast-signals/nssp.md @@ -43,6 +43,7 @@ As of May 2024, NSSP received data from 78% of US EDs. The percent visits signals are calculated as a fraction of visits at facilities reporting to NSSP, rather than all facilities in the area. `county`, `state` and `nation` level data is reported as-is from NSSP, without modification, while `hhs`, `hrr` and `msa` are estimated by Delphi. +State and HSA-level values are calculated and published by NSSP; County level values are not published individually, but are approximations copied from the HSA the county is in (every county in an HSA will have identical values). ### Geographic weighting As the original data is a percentage and raw case counts are not available, `hrr`,`msa`, and `hhs` values are computed from county-level data using a weighted mean. Each county is assigned a weight equal to its population in the last census (2020). Unreported counties are implicitly treated as having a weight of 0 or a value equal to the group mean. @@ -69,6 +70,8 @@ The following states report no data through NSSP at the county level: CA, WA, AK South Dakota, Missouri, and territories report no data through NSSP at the state level. +The only completely non-reporting state is Missouri. + ## Lag and Backfill @@ -84,6 +87,9 @@ Counties with `NA` values are as originally reported in the dataset from which t ## Limitations +As noted above, only state and HSA-level values are calculated and published by NSSP; County level values are not published individually, but are approximations copied from the HSA the county is in (every county in an HSA will have identical values). +The HSA (Health Service Area) definitions used are known as ["NCI Modified"](https://seer.cancer.gov/seerstat/variables/countyattribs/hsa.html). + There is substantial missingness at the county level. This tends to impact more rural and lower population locations. See the [missingness section](#missingness) for more information. Not all counties contain reporting EDs, including in states where NSSP reports state-level data. @@ -104,4 +110,4 @@ Some low population counties occasionally report outliers, e.g. 33.33%, 50%, 100 This source is derived from the CDC's [Respiratory Virus Response NSSP Emergency Department Visit Trajectories dataset](https://data.cdc.gov/Public-Health-Surveillance/2023-Respiratory-Virus-Response-NSSP-Emergency-Dep/rdmq-nq56/about_data). There is another version of the dataset that includes [state data only](https://data.cdc.gov/Public-Health-Surveillance/2023-Respiratory-Virus-Response-NSSP-Emergency-Dep/7mra-9cq9/about_data). -This data was originally published by the CDC, and is made available here as a convenience to the forecasting community under the terms of the original license, which is [U.S. Government Public Domain](https://www.usa.gov/government-copyright). \ No newline at end of file +This data was originally published by the CDC, and is made available here as a convenience to the forecasting community under the terms of the original license, which is [U.S. Government Public Domain](https://www.usa.gov/government-copyright).