Study population and setting
The authors analyzed daily GPS location data from approximately 15 million smartphones to estimate differences in physical distancing (using general movement and visits to non-essential services) at the county level among 3,025 counties in the United States from March 9 to May 29, 2020, compared to the period before March 9, 2020. Associations among partisan identity, physical distancing, and COVID-19 infection and death rates were investigated. Partisanship was measured by county-level vote margins between the Democratic candidate (Hillary Clinton) and the Republican candidate (Donald Trump) in the 2016 presidential election. The authors used mixed effects models to estimate the association between partisanship and physical distancing. Viewership of Republican-leaning and Democratic-leaning media was measured with data from SimplyAnalytics, and tested for associations with physical distancing. Mediation models were utilized to test associations between partisanship-related physical distancing and infection and fatality growth rates.
Summary of Main Findings
Average reductions of 21% in general movement and 31% in visits to non-essential services were observed at the county level. Trump-leaning counties exhibited an average 24% decrease in physical distancing metrics, while Clinton-leaning counties exhibited an average 38% decrease during the same period. From mixed effect models, there was an estimated 0.11% reduction in physical distancing for each percentage increase in the vote margin favoring Trump. Physical distancing was highest from March to mid-April and declined afterwards in both Trump-leaning and Clinton-leaning counties. Differences in physical distancing by partisanship widened as the pandemic progressed. The association between partisanship and physical distancing remained in subsequent analyses when counties were collapsed into dichotomous partisan categories and when adjusted for a number of covariates including race, age, income, cases per capita, commute time, type of employment and state-specific policies among others. Viewership of Republican-leaning media (e.g., Fox News) was associated with reduction in physical distancing over viewership of Democratic-leaning media (e.g., MSNBC); this association strengthened as the pandemic progressed and was observed even when accounting for 2016 voting partisanship. Mediation analyses provided some support for the hypothesis that partisan differences in physical distancing affected infection and fatality growth rates.
The authors considered a wide range of possible confounding variables at the county level in analyses. Viewership of partisan media was considered separately from the primary measure of partisanship.
Aggregated mobility data are not perfect proxies for physical distancing behaviors. Data at the county level may mask individual-level variation; the results do not necessarily imply that individual Republicans are less likely to comply with stay-at-home orders and physical distancing compared to their Democratic counterparts. County-level variables included as possible confounders in models were crude and likely did not capture all salient differences between Republican and Democratic counties. Models only included state-level social distancing mandates; regional and municipal regulations and recommendations may have influenced behavior. Compliance with other public health measures such as mask-wearing or staying 6 feet apart were not taken into consideration. Adjusted variables such as employment did not necessarily account for the variability in physical distancing within different employment settings. Differences in counties may exist such as the need to travel further to access essential services or goods. Finally, the construct of partisanship was not well defined; other characteristics of county residents (e.g., levels of distrust for authority, social alienation) might influence both the partisanship measure and physical distancing behavior.
This is one of the most comprehensive analyses to date of the relationship between partisanship and physical distancing in the United States.
This review was posted on: 5 December 2020