Regression estimates across outcome and network measure models
| Model (1) | Model (2) | Model (3) | |
| Panel A: COVID-19 mortality rate—population level | |||
| Network measures | |||
| PCP/non-PCP degree centrality ratio | −0.254** (−0.487 to –0.022) | ||
| Betweenness centralisation | −19.19** (–36.31 to –2.070) | ||
| Eigenvector centralisation | −11.17*** (–19.05 to –3.293) | ||
| County level controls | |||
| Mean household income | 0.0003* (−0.0000 to 0.0006) | 0.0003** (0.0000 to 0.0006) | 0.0003** (0.0000 to 0.0006) |
| Unemployment rate | 447.4*** (295.0 to 599.7) | 461.5*** (306.9 to 616.2) | 462.3*** (308.5 to 616.2) |
| Diabetes prevalence | 6.575 (−41.85 to 55.00) | 18.13 (−31.07 to 67.32) | 19.79 (−29.23 to 68.82) |
| % 65 and older | −72.12*** (–107.9 to –36.32) | −77.66*** (–114.0 to –41.29) | −78.50*** (–114.6 to –42.44) |
| % females | 158.5*** (52.39 to 264.6) | 150.6*** (43.49 to 257.7) | 142.7*** (35.79 to 249.6) |
| % non-Hispanic black | 84.68*** (62.31 to 107.0) | 81.32*** (58.50 to 104.1) | 80.28*** (57.41 to 103.2) |
| Fixed effects | Yes | Yes | Yes |
| N | 2573 | 2541 | 2541 |
| R2 | 0.434 | 0.426 | 0.427 |
| Panel B: COVID-19 mortality rate—case level | |||
| Network measures | |||
| PCP/non-PCP degree centrality ratio | −12.82** (−25.05 to –0.591) | ||
| Betweenness centralisation | −1642.6** (−3085.7 to –199.4) | ||
| Eigenvector centralisation | −595.8** (−1155.3 to –36.20) | ||
| County level controls | |||
| Mean household income | 0.019** (0.0011 to 0.0369) | 0.0244*** (0.0080 to 0.0408) | 0.0242*** (0.0078 to 0.0407) |
| Unemployment rate | 6802.6* (−483.7 to 14089.0) | 9376.3*** (2753.4 to 15999.2) | 9506.0*** (2878.1 to 16134.0) |
| Diabetes prevalence | 849.7 (−2226.4 to 3925.7) | 2518.7** (32.67 to 5004.7) | 2632.3** (156.8 to 5107.8) |
| % 65 and older | 3250.5** (424.5 to 6076.5) | 2006.8** (73.35 to 3940.2) | 1877.3* (−49.95 to 3804.6) |
| % females | 11083.2*** (5455.8 to 16710.6) | 8697.4*** (4215.6 to 13179.2) | 8308.9*** (3769.8 to 12848.0) |
| % non-Hispanic black | 1353.3*** (666.6 to 2040.0) | 1249.9*** (555.2 to 1944.5) | 1188.1*** (493.9 to 1882.3) |
| Fixed effects | Yes | Yes | Yes |
| N | 2573 | 2541 | 2541 |
| R2 | 0.260 | 0.285 | 0.285 |
| Panel C: COVID-19 case rate—population level | |||
| Network measures | |||
| PCP/non-PCP degree centrality ratio | −2.278 (−12.10 to 7.539) | ||
| Betweenness centralisation | −211.7 (−798.8 to 375.5) | ||
| Eigenvector centralisation | −192.9* (−405.7 to 19.88) | ||
| County level controls | |||
| Mean household income | −0.0003 (−0.0081 to 0.0075) | 0.0014 (−0.0062 to 0.0090) | 0.0012 (−0.0063 to 0.0088) |
| Unemployment rate | 11176.1*** (7112.5 to 15239.7) | 11696.9*** (7622.2 to 15771.6) | 11693.3*** (7633.5 to 15753.2) |
| Diabetes prevalence | −408.6 (−1756.3 to 939.1) | −502.9 (−1859.0 to 853.2) | −478.9 (−1832.8 to 875.0) |
| % 65 and older | −7080.3*** (-8109.5 to –6051.1) | −6842.0*** (−7852.7 to –5831.3) | −6840.1*** (−7846.1 to –5834.2) |
| % females | −6962.7*** (−11960 to –1965.4) | −6082.0** (−11061.0 to –1103.0) | −6225.1** (−11250.6 to –1199.6) |
| % non-Hispanic black | 2407.9*** (1856.5 to 2959.3) | 2358.2*** (1791.2 to 2925.2) | 2341.7*** (1775.7 to 2907.7) |
| Fixed effects | Yes | Yes | Yes |
| N | 2573 | 2541 | 2541 |
| R2 | 0.497 | 0.504 | 0.504 |
Significance is indicated as: *p<0.1, **p<0.05, ***p<0.01.
95% CIs are reported within the parentheses, and these are based on robust SEs.
PCP, primary care physician.