This study is an investigation of preoperative asymptomatic COVID screening nationwide. The hypothesis is that because these tests are performed without reference to pretest probability of COVID-19 disease, unlike tests based on symptoms or close contact with infected individuals, these studies may represent a more unbiased sample of the local population prevalence of asymptomatic COVID disease burden.

Study will gather publicly reported, aggregated statistics on positive COVID tests over time and across geographically diverse parts of the United States, summarized weekly, from the onset of the pandemic in Spring 2020 to the present time. Study will also gather contemporaneous data on weekly community COVID cases diagnosed, local positive test percentage, hospital admissions and ICU admissions for COVID-19, and deaths from COVID 19. Similar data will be obtained from a coalition of approximately 20 academic medical centers from around the United States, with Wake Forest School of Medicine, Department of Anesthesiology serving as the coordinating center. No individual patient information will be collected. Aggregated testing data, hospital disease burden, and local disease prevalence are all publicly reported.

Data will analyzed as interrupted time series.

Inclusion Criteria:

• having preoperative asymptomatic COVID testing
• > or = 18 years of age

Exclusion Criteria:

• None

Publicly reported aggregate data on asymptomatic preoperative COVID tests (no individual patient information)