State-level Stay-at-home Orders and Objectively Measured Movement in the United States During the COVID-19 Pandemic.

Bourassa, Kyle J

OBJECTIVE Social distancing has been one of the primary interventions used to slow the spread of COVID-19 during the ongoing pandemic. Although state-wide stay-at-home orders in the United States received a large degree of media and political attention, relatively little peer-reviewed research has examined the impacts of such orders social distancing behaviors. METHOD This study used daily GPS-derived movement from 2,858 counties in the United States from March 1 to May 7, 2020 to test the degree to which changes in state-level stay-at-home orders were associated with movement outside the home. RESULTS From early March to early April, people in counties with state-level stay-at-home orders decreased their movement significantly more than counties without state-level stay-at-home orders; 3.1% more people stayed within 1 mile of home and 1.6% fewer vehicle miles were driven per day. From early April to early May, people in counties within states that ended their stay-at-home orders increased their movement significantly more than counties in states whose stay-at-home orders remained in place; 1.2% fewer people remained within 1 mile of home and 6.2% more vehicle miles were driven per day. The magnitude of changes associated with state-level stay-at-home orders were many times smaller than the total changes in movement across all counties over the same periods. CONCLUSIONS Stay-at-home orders were associated with greater social distancing, but accounted for only part of this behavioral change. Research on behavior change would be useful to determine additional interventions that could support social distancing during the COVID-19 pandemic.